Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB GT V8 Factory Originals Technical - Why do people Still Use the Rover V8?

The BOP/Rover engine was nice in it's day but we are talking seriously out of date technology here in comparison to today's available engines.

The options for smaller high tech high output are many - Miata , Ecotech etc.

Is it old hot rodders who want to play with MGs and are not used to anything but American V8s?

I am thinking about doing a swap into an MGA (non-stock body, so no loss to the traditionalists) but wouldn't even think about using the V8 when I could use a 60 deg. GM V6 that fits better and puts out more power and torque.

And what is the big deal with carbs? More old technology. FI is so much better from the point of view of power and emissions, although ti does require a modicum of thought to adapt from one car to another. Maybe that's what puts people off.....;-)
Bill Spohn


Take a look at what those rice burners cost and then assess what you want to do. V8's provide much more power for a cubic inch or lb than the jap or american v6 or 4 cylinders. Why go through the hassle and cost of conversion for only half the gain?

Im in the process of beginning a conversion on my 78 B and initially thought I would go with a v6 and auto. Upon pricing those engines decided I would go for a V8 just for the hp and because there is so much more available in the US. I can buy a longblock Ford v8 for $3000 that delivers 350 hp. I cant even buy a 150 hp miata/Jap engine for that kind of money.

The other thing to consider is the actual hp you get, the BOP aluminum V8 is rated at 200 hp which in today's new tech world would actually be closer to 300 hp.

I cant speak to a Rover engine and I suspect it is much more expensive than a BOP V8 or Ford. A guy on the east coast quoted me 8500 turn key for the engine,tranny, clutch etc.

Originally I had wanted to do a carb, but a guy told me efi is a better solution in that you end up with an engine easier to tune and set and more economy on the road not mention it will pass emissions testing.

Anyway, those are my thoughts.

CW Strong

The last three running rover engines I bought cost the equivalent of about $70 each. You probably couldn't buy an air filter for a miata/mx5 up here for that money. An MGA with a nice engine in would be nice though.... if money wasn't a problem, I bet one of those new 4.4 litre BMW v8s would be good.
Nick Bentley

Bill, my thoughts exactly.
It seems many are convinced it is the way to go because "tha's how the factory did it" at lest in the GT.

Problem is the factory was hobbled by a choice of one item and even that was out of production when Rover got hold of it.

I see no reason why we should slavishly follow the same choice some fifty years later but there are those who consider the thing the only engine ever built.

Personally I have given up trying to suggest alternatives to it as there are none so blind as those who will not see.

Cheers , Pete.
Peter Thomas


Just not true. Although in UK RV8 is cheapest bang for buck and efi is used extensively. The 4.6 and up are available and well supported for extra bhp

The K conversion is becoming popular and perhaps KV6 waiting in wings.

Another example

Even interest in using Diesel.

Reinventing wheel just tends to be more expensive.



>we are talking seriously out of date technology....
>And what is the big deal with carbs? More old technology.

If we wanted the latest in high-tech, would we be building MGBs? Given that the newest MGB is 25 years old, I don't think the average MGB owner feels the need to live on the cutting edge of technology. For those that do feel the need, fine, use what you like, but don't fault those who don't... :-)

My 2Ę
Rob Edwards

Bill, I believe that those who want the power of a V8 chose the Rover because it not only fits, but its relatively light weight and has the ability to be tuned well beyond any Japanese 4cyl. There are many parts available to quickly perform the swap, and fuel injection is possible without having to design a new system or fit a generic moderate-performance aftermarket system. The 4.6L is not the BOP engine of the 60's. It also doesn't cost as much as the Cosworth or many of the other "better" (in your opinion) options. Its not as cool as a Viper V12 or a turbo/intercooled 12,000rpm race motor, but it gets the job done, and on a budget I might add. If we weren't all on a budget, would we still be messing with Bs? Hmmm...
Jeff Schlemmer

The 4.6 engine is a reasonable choice for those living in Britain, but not easily obtainable elsewhere. While based on an old design, I respect what TVR, for instance, did with it (I recently sold my TVR race car - it will be running at Nurburgring this month), and the recent versions have certainly been properly updated.

The the fact remains that the original 215 did not produce the power or torque of the 60 deg. GM V6 and is more difficult to install, taking up much more space in an engine bay.

Take a look at

for a comparison. The SD1 version did produce a bit more (a claimed 185 as I recall). I used to have a buddy who raced an old Canam style sports racer (I was racing an MG) and used a 215 - he said that the actual horsepower was under 200 on the best versions (of course they were tunable from there) and Chuck, you are going the wrong way when you say that 200 then is 300 now. The old gross figures were higher, not lower than the new net ratings.

As for weight, the 3.4 GM engine weighs about 30 lbs. less than the 215, has around 220 BHP net with very modest mods and runs with an ECM that fires MPI injection, gets better mileage and runs clean.

I know some people just have to see great bunches of carbs in their engine compartment, but it isn't necessarily the best way to go. I am quite familiar with both schools - I own a British car with a big block Chrysler and a sixpack, and my Lamborghini uses 6 side draft Webers. I race an MGA Twincan with Webers, but would love it if the vintage rules allowed me to use injection.

Aside from being a pain to tune (thankfully not necessary very often) a properly implemented modern engine management system on either would result in more power and better fuel economy.

When you put a non stock engine in an MG, you are starting with a fresh slate. If you go for a 40 year old design for nostalgic reasons, OK, a valid choice and yours to make. But I think that too many people opt for the bad choice out of ignorance or fear of having to actually learn something.

I have just picked up an MGA based car that I have to re-engine and I think that my choice will almost certainly be a 60 deg. GM V6. And for those that say you can't get the power out of those engines if you want to, my daily driver is a 1988 Fiero with a 3.2 turbo producing 300 BHP, dead reliably for 100,000 km now (and no, I don't think I'd want that much power in an MGA based car....)

For the street, depending on what you want in the end, the 4 cylinder Miata etc. route isn't to be disparaged either. Imagine your MGB with 140-160 BHP, dead reliable.

(If anyone wants to see pictures of what I am talking about let me know as I have a few on a website)

Bill Spohn

PS to Paul - I really liked that Cosworth MGB! Very nicely done.

I'll bet someone will try an Ecotech MGB before long - 140 BHP stock, but they have produced up to 1000 BHP out of a 2.2 for drag racing.......
Bill Spohn

WHat I find interesting is the whole "techno geek" thing in the car industry. People thing motor swaps and tuning cars is all about the pinnacle number. "I have 5000hp 4cyl, so my car is the best/fastest and beats all those V8's.

NOT. Sure a V6 can get 300hp these days, they can even get 1000hp (turbo supras) BUT they 99.9% of the time are not enjoyable to drive! To reach that extreme top number means sacrificing the rest of the power curve for the motor.

I tell you I would rather have a 200hp V8 than a 300hp V6 for a daily driver/non track car. and I would definitely feel more comfortable leting the wife drive it too.

I chose a FORD V8 for many of the reasons you stated in regards to the 210/rover. Availability, aftermarket support etc. I am sure the V6's are allot of fun, but so are V8's, it really is an apples to oranges comparison...

Here is my dynorun sheet. this is with 100% STOCK 94 mustang set-up, NO tuning, running rich do to limp mode in ECU from check eng light. Stock intake and cam.

Nice shallow curve, that is what distinguishes a V8 from a V6 or 4cyl or comprable power. Nothing agains the 6cyl and 4cyl guys. I have owned both in the past and loved them too, but they are just completely different power types..
Larry Embrey

Larry - no question, the Ford V8 gives a really flat torque curve (it also adds weight over the original engine of course), but we got started talking about the Rover V8, not the various other V8 options - Ford, SBC etc.

The V6 gives better torque and power than the Rover - which is logical, as it has about the same displacement, right.

Here's a way to really tart up an MG engine swap. This guy has built a Fiero conversion to look like a Lamborghini Diablo. One could question his sanity, but let's not go there.

What he DID do is create a plastic shell/cover for the V6 engine that looks like.....well take a look yourself.

The question is, if I use a GM V6 in my Jamaican project, can I resist seeing what he'd want for that engine do you thing that would look in an MG engine bay?
Bill Spohn

Larry - one further thought about technogeek vs. torquemonster.

I've got both.

This is a high compression 6.2 litre American V8 with 3 2 bbls on it:

This is a little bitty 4 litre engine:

Both put out similar horsepower, the first puts out about double the torque, and both cars weigh the same within 100 lbs. or so.

I wouldn't say either was superior to the other and both are just great fun.

While I do not subscribe to the 'torque uber alles' line (if I am reading you wrong, say so), I completely agree with your statement that playing the peak power numbers game is a big mistake.

As for my Fiero engine, it has a couple of hundred ft-lbs of torque low down and it certainly has sacrificed none of that as a trade off for power - in fact it has way MORE low down torque than a regular engine.

If you like rumbling V8s, great. Let me know when your V8 car can match my 0 -60 in 4.6 secs and 13.2 quarter in my daily driver that gets 20 mpg and that my wife happily drives. ;-)

Your assertion that high output small displacement engines lack torque only holds up for non-boosted engines.
Bill Spohn

Bill, The 302 adds 17lbs to the front of the B, and there are ways to offset The Fast Cars front crossmember, alum radiator etc.. My 302 has dyno'ed in at 323hp at the rear wheels. Its a pleasure to drive with all the torque that it has, I can run at 85 mph all day long at 2200 rpm, the motor isn't even working at that rpm!!! And I'm getting over 25 mpg at 85 mph. I have the T-5 tranny with .63 OD and a 3.25 rear ratio. OH, did I mention that I sell the headers for this conversion, opp's that right were not supposed two advertise on this site, sorry
Steve Carrick
Coyote Eng. LLC
Steve Carrick

Steve - very little additional weight indeed.

Tell me something - that 5th gear on the motorsports T5 was designed for economy and CAFE numbers, very long - do you really find it to be any better than the more usual 0.8 OD ratios or is it just that that gear set has better intermediate ratios so you take what you get with the 5th gear?

And as for your headers for the MGB, an easy task compared to the tighter confines of the MGA engine bay! ;-)
Bill Spohn

My rear axle cannot handle what is required to get the 13.2 1/4mile, but she routinely ran 13.8 @102mph+. Stock rear so traction off the line was NILL, BUT I still am getting 25mpg avg with the car. 195rwhp verified by dyno. That number will climb greatly once I get her tuned and leaned out.. Not to mention putting a rear end with posi and gears that let me use 1st gear again and allow the motor spin under 3k on the highway...

That said you are correct about the 215. I thinks it's time has past, hence the reason I went for the 302 FOUR YEARS ago... I saw te new day dawning and went for it...

I was not saying torque solves all probelms. I was more refering to the "peak numbers game" in which we are of the same opinion...

It really does come down to what the owner/driver wants. I just took offence to the V6 vs V8 debate as it seems to pop up every other month and there really is no one better than the other...
Larry Embrey


Whats that Cosworth cost. It looks like a great conversion though. As to weight issues, with the Ford you can skim alot of weight with Aluminum heads. Also, like I did, get rid of the rubber bumpers. I bet I took 75 lbs off the nose with that alone.

I agree with Steve on the hp/torque figures, my Corvette output is rated @ 350 hp and 400 lbs of torque but runs @ 1800 rpm around 60. I drive it 75 and 80 comfortably and get 30 mpg on the freeway. The vette weighs 2850 lbs.

My concern with other conversions, ie Pontiac 3800 etc is the availability of performance products for those engines. Not being a gear head, is it possible to convert those side mounted front wheel drive engines to our applications in the B?

CW Strong

bill, have to admit i winched when i saw the heading, this topic reoccurs and is debated and sometimes gets heated. as i have both a v8 and 3 v6's, 2 in mg's and 1 in a mini, i think the conversion is what you want. simple facts on hp, torque and weight mean very little. if we really wanted an apples to apples or oranges to oranges we would have to do a cost v value matrix. but either way nothing is solved. really just a personal preference. me? i think if you want a v8 the 302 is far and away the best choice for power and parts availability, if you want the most power for the least cost and simplicity than v6 is the way to go. just my 2 euros worth, jim
james madson

Bill, this is an oft repeated argment/discussion, as others have said. If you are raising the issue to promote a bit of interest on a dull Sunday evening, well good.

All conversions MG or otherwise, are usually very personal decisions, based upon the knowledge, goals, & pocketbook of the individual, therefore, there is no right or wrong conversion, as long as the owner is happy with the results. While you want a higher tech motor for your MGA, some would argue that the old twin cam was extremely high tech for its time, and a worthwhile conversion, if terribly expensive. Others would say just supercharge the stock MGA motor. In the past, many MGA's were converted, to 289 Fords, while a few received the old Flatheads. Your taste, experience & pocketbook will probably dictate a very different result, not better or worse, just a reflection of your

As to why people still use he old 215/Rover motor, it is because it is such an easy conversion, well documented, with tons of available parts and powerplants, and provides a very enjoyable vehicle, for most tastes. No welding is required if starting with a rubber bumper car, minimal cutting or none, if using the old block hugger headders, so it is an ideal first conversion.

And yes, lots of us are old hot rodders, although I converted one car to EFI & love it. I only wish I could find a simple way to install EFI on the Buick 300 in the other car.
Jim Stuart

The nice thing about today, you can build a 440 mopar to a volvo B 20 to the ford, G.M. V-6 & put them in a B or midget! I have a 4.2 Rover with the F/I under the stock ALU. hood & when your done it all comes to (There is an ass for every seat) & what do you what yours in?
Glenn Towery

Jim, the Twincam is still a great motor and way better than the pushrod MGB engine.

I've been racing one for 30 years and have a race engine sitting in the garage - only problem is that it takes race gas at 12:1 compression, and the power band is 5000-7800 RPM.......not exactly useful on the street, although the 170 bhp would be fun..

Bill Spohn

I had a request for the Miata pic - it is here:
Bill Spohn

Agreed, there are better motors ie lexus V8.Very difficult to register. Can be done, costs $$ and lots of time/effort meeting government regulations.
But the Rover motor MGB is very easy to register here in OZ.
I quite like rumbling around the place in the V8. It sounds fabulous and is so smooth and easy to drive.
Re-sale value is also fabulous (I am not rich enough to disregard this factor). In the public mind the Rover motor MGB still manages to qualify as a "classic", even with modern fuel injection etc. It has authenticity. Anything else is a hot rod and although lots of fun, you've done any money you put into it.
Even more power? Supercharging this motor (or varient) has been done before many times (spitfire) so is easily done.

All of the above - the MGB in particular has proved a versatile host to a whole range of engines - of them all, the V8 has proved the most enduring - partly because spares have been plentiful but mostly because the conversion has a good road reputation - over here there are plenty of folk with a soft spot for the V8 -it's fast enough to loose you your licence - it takes the car to the limits of the stock suspension and when it worn out there is always someone to pay good money to take it off your hands.

One recognizes of course, these are not matters which concern those who have enough money to spend on Italian exotica.


Peter - good point about resale value - I just assumed that cars with engine swaps have little value, but when I think on it, the fact that the factory did a similar version WOULD tend to enhance resale!

Roger - I understand that the Rover engine makes much more sense for people in the UK, based on cost and reliability. And as for Italian exotica, I'll bet I paid less for my old Lamborghini (an Islero S) that some of you guys have put into your MGBs! Any of the Lambos after that one ramp up very sharply in price, and I also find that their owners are too self-impressed to be bothered with in many cases - the owners of older models are just old car guys, most of whom bought their cars long ago and perhaps couldn't afford to buy them at today's prices.

Now - anyone know if such a thing as engine and trans mounts for a GM V-6 are available for an MGA chassis? No problem for MGB, but I haven't found any MGA kits yet.

The kit car I am dealing with is this:
Bill Spohn

If you want high tech light and fast. A mitsubishi 2.0 turbo can be built to any level of performance your wallet can stand up to 1000 H P. A tame streetable version could run 12s easily. Personally I want a wrecked lexus 400 for a donor car on my next conversion. Nothing like a V8 rumble. Who cares about 1/4 mile times anyway the idea is to have fun.
Here in Colorado you can do any thing you want to a 30+ year old car and still register it. We put a chevy 454 in a Hillman SW for a friend set up like a pro street. Cars 1959 and older with collector plates are exempt from air test. 1960 through 1974 have to meet a 2 speed idle test of 5.5% CO and 1000 PPM HC. Once to get collector plates for the first time or if sold to another owner.
R J Brown

rj you need to move to mn, any car 20 years or older can get collector plates, one time fee of $90 and never any tabs. NO cars or trucks ever have to pass any type of emissions testing, we already have enough taxes here without that added one, jim
james madson

Bill, when I built my MGA with the 215 Buick five years ago, there wasn't any ready made engine mounts. I had to make everything. I don't know about now, and yes, I do love that V8 rumble. Lyle
Lyle Jacobson

Seems to me that the older engines just fit better with the theme of what I'm doing, which is hand-building a vintage vehicle to my own taste. My objective is to have a fast, well-handling touring car. Not to shred tires, bust up differentials and ujoints, or make every single stop light a race. Just so I have enough power to get away from the tail-gating SUV on my butt and give myself a thrill by taking it thru the twisties, or just enjoy gazing into the engine bay of my creation. To me, a modern engine just wouldn't 'fit' the character of a chrome bumper MGB. If you wanted something other than a V8, that would fit the vintage style, you'd have to go with a four-cylinder Offy.
If I wanted something that would sound like a V6, I'd build it. But then, that would never happen.....
Proudly Retro

Jim $90.00 forever? I'm jealous, just paid $120.11 for 5 years on my 58 MGA. Drove it for the first time in over 10 years. That Mazda 12a rotary in it kicks a**. Next conversion will be a V8.
R J Brown

Interesting - that Mazda rotary was always a fairly blocky engine, and although I've even seen them in Spridgets and Lotus 7 (Rotus?), I always wondered if they'd go in an MGA and clear the frame rails.

I kind of like the idea of an MGA that goes "Hmmmmmmmmmmmmmmmmm".

Frankly, my first choice for a swap into the Jamaican would have been a Honda S2000 package, had there been any available at a reasonable price.....something about that 9000 RPM redline.......
Bill Spohn

The rotary sits on stock motor mounts! I welded up a simple 1/4" plate that locates the engine low in the bay. A custom header (from a kit) goes under the engine and back on the stock side. The rear trans mount was changed to a RX7 mount. Had to cut out the stock uprights. The tunnel had to be widened a little to clear the starter. Shifter is in stock location. All gauges are stock except tach and it is MGB inductive. Used a high output electric AC fuel pump and a regulator to feed a Delorto side draft carb. Dist is Mazda RX7 electronic. Engine (12a) and trans (4 speed)from RX7. Local Mazda shop ported the engine for more power. This is absolutly the simplest conversion possible. I also used MGB front suspension and disc brakes. Still haven't broken the stock rear end. A Datsun 280Z u-joint yoke is the same size as the stock differential and was used on the back of a RX7 driveshaft. The stock MGA water temp gauge fit the stock hole in the engine. The oil pressure fittings were the same size. An adequate cooling system is the only real concern.
R J Brown

bill., you betcha, the s2000 would scream, i have a vtec mini and the sound and feel when it hits the 8500 red line is a rush. RJ, i would love to see that rotary A, would that be an MGRA? or MGA typeR ? anyway it sounds very cool, send pictures please, what rear end are you considering? jim
james madson

RJ, my only concern would be cutting out the supports that run from the top of the firewall down to just behind the shock platforms. That is what you meant, isn't it?

Cutting those out might not be a very good idea in the long term, as I believe that they provide considerable rigidity to the front suspension area.

Not being an engineer, I can't analyse the strength of the remaining structure. I am reminded of a V8 conversion to a TR3 many years ago. The bolt-in cross brace between the front suspension towers was in the way, so the guy just removed it and left it out. It DID take almost a year for the suspension towers to fold in on each other, leaving an immobile knock-kneed TR3, though........

I have seen installations where these 'stays' were replaced with alternatives of greater or lesser strength, relocated to avoid what the originals fouled.
Bill Spohn

If the stock rear end fails I would probably go with a 9" Ford. It is almost a universal hot rod item. Any length, brakes or gear ratio. An engine picture is on this website
R J Brown

Bill you misunderstood, the only piece of the frame that was cut is at the rear trans mount. The pieces you ask about were not touched. When the MG DOC put his V8 in an MGA he cut and reinforced those supports to clear his headers. The rotary fits. Bill the rotary is only 12" wide plus 3"wide intake & header on right side and on left side spark plugs. The header clears the support you ask about by over 1/2 inch with engine centered. The room on the left is greater. I can take pics if you want.
R J Brown

Hmm - maybe I should start looking for an RX7 turbo.....

Naw, already have the V6.

Now if I can just remember where I stashed my MGA disc brake wire wheel front suspension!
Bill Spohn

Regarding "Why use a Rover V8?"

Good questing because a Chevy block with aluminium cilinder heads is the best available option. It has the same dimensions then the Rover V8, still has acceptable weight and parts are easy to find.

American Speed f.e. delivers turn-key 450 HP engines at a very reasonable price. I bought a turn-key 4.1 Rover V8 from V8 Developments although I could have bought a 450 HP Chevy for the same budget including gearbox! But... bying in the US would have its consequences concerning after-sales service.

So that's why I (as a belgian) sticked to the Rover V8.
Tim De Vits

i cant aford to put petrol in my 1800 fuel costs a fortune in the uk.why not spend around a thousand pounds use your orig and fit a fast road head fast road cam 4 branch maifold. i get 120bhp at the wheels alot of fun.i dont think these cars are made to have poweful engines in them. i get past 70mph i dont feel safe if you want a fast car which is cheap just get you self a chimera or griff 0 to 60 around 4 seconds these cars have moified rover engines between 4 l to 5 l blow any american car away

Daz,Daz, Daz....I really do not think you get it when it comes to V8/V6 converted cars...sure there is a place for modified 1.8L engines...and I respect that..but you have just not lived until your mgb blows away a Mustang or Camaro at a stoplight...god, it takes a week to get the smile off your face (especially after all those years having Festivas and Escorts kick our cumulative mgb butts)...and be careful when you say a chimera or griffith will blow away any american car...and besides, you loose the element of surprise and shock!! :-)
Mike Maloney

I've noticed that middle aged guys in new BMW's and young guys in powerful utes (pick ups)will attempt to drag me off. About one in three. I affect not to notice them as they become a dot in the rear view mirror.

Actually, I can't say that the economy of the car has gotten worse. The fuel injection is way way more efficient than the SU's, and the car has gotten lighter by about 30 kgs. If I drive with about the same amount of zing as the 1800 it's slightly better.

I've had a 1980 SD1 sitting out-back awaiting it's turn to be a donor for a future project. After this thread I am wavering. Every time I need to move it about for car shuffeling I am re-impessed with the "little" 3500 engine's performance. Oh well...several other projects are currently on the bench-top so the decision remains in the future. I'll continue to attend this wholesome debate. M
Marc Judson (2- 1978's)

Mike, I know what you mean about that smile. First time it happened I still had the 1800 in the car and just barely got 'em, but the memory still lingers 2 decades later. These days it's both a bit more routine and a bit more extreme, but still a ton of fun. But I've lost the element of surprise. I decided I had to have the blower the day a new BMW V8 sedan stayed with me. That one was a bit of a shock for *me! :-)
Jim Blackwood


Get that Swift in the air. Be more fun than an MGB V8. Although there is no reason not to have both. See;

Edd Weninger

I have fitted a SD1 engine in a mgb, I donít regret. The engine is properly tunned, close ratio gear into LT77 gearbox. This mgb is a good car. The 3.5 rover a good engine.

Before this thread heads off to the archives, I thought I'd add my two cents.

Since MG put 'em in the GT and made them a bolt-in swap for the late roadsters, it is defacto factory sanctioned! You can put a Buick/Rover V8 in an MGB and stay in good graces with your local LBC car club.

Like Jim said, it is an easy swap. Also, 160-220 HP is plenty for many of us.

"The BOP/Rover engine was nice in it's day but we are talking seriously out of date technology here in comparison to today's available engines"

Hah, so is the rest of the car! Doesn't mean I'm parking my MGB V8 and buying a Miata. :)
Carl Floyd

Yeah, Carl - when I started this I figured the factory sanction thing accounted for a lot of the attraction of using the Rover engine. As for an easy swap - there are even easier one (GM V6 for instance) but without the factory connection.

I agree that a moderate amount of power is appropriate given the dated chassis. Some of us get an added kick from using modern technology with fuel injected engines with electronic management, while others just rip all that stuff off and stick an old-tech carb on. Different strokes, I guess.

Once you leave the safe environs of conventionality and decide to put a non-stock engine in a car, I guess the whole field is open to you to go for whatever rings your own personal chimes.

I guess it surprises me a little to see no one looking at compact engines like the Northstar or the new Mustang V8, but part of that may be the challenge of being a pioneer, at least as far as MGBs are concerned.

Maybe I am more willing to settle for a 'moderate' solution for my MG project because I already have other high powered V8 stuff at hand and can always get my torque jollies with one of them.

Anyway, it's always an interesting discussion, thanks guys.
Bill Spohn

The new Mustang motor is still the 4.6L mod motor and is absolutely MASSIVE. There's no way it would ever fit in a B without widening the car by about a foot.

I have, and enjoy my Rover V8 and have thought about putting in my 4.2L that has been sitting in the garage for 2 years, and adding a vortech supercharger to that. (That should be a fun project!)

My father is starting to consider getting a B, and if he does we'll put a 302 in it. I may end up with the best of both worlds!


Just to add an opinion from a humble engineer who hasn't seen it all and done it all, and who has a life outside racing cars ( I am jealous of you high performance guys of course)- you know job,house, wife, kids, decorating, school, football teams, sons motorcycle, daughters car etc etc.
I have been building my Rover engined car for about 3 years using a 3500 EFI and gearbox.
All the problems I encounter are small and you just chip away at them.
The EASY bit was getting the engine in. We all know that fits. The transmission tunnel was modified with info from the speedpro "how to give your MGB V8 power". All the rest of the bits are off the shelf from MGB Hive in the UK or V8 Conversions. I am spending ages and ages making brackets to hold the coil, header tank, air flow unit, washer bottle, fuel pump, fuel filter etc etc.
BUT its a big job. If you are starting with just your car and no bits ( no spare engine lying on the floor of your garage that might be worth a try!!)

So anyway I liked my B with 90bhp so I reckon with almost the same weight and 190bhp it should be all I need.( Donor CAR cost £150 )
My friend had a TVR Chimera which he finally sold because it had TOO MUCH POWER. Wife wouldn't drive it, and he had to be careful on wet days! That's after the TVR development engineers have sorted it. I don't think a high power MGB is going to be so well mannered.
So do what you feel, but if you want a budget sports car and don't want to spend megga bucks doing it, or even more important devote your life to it - there's nothing wrong with the tried and tested route.
As long as it puts a smile on your face :-)
P A Hawkins

Good point Pete. Nothing wrong with it whatsoever, and lots of things right. I think most of us here also really liked the way our cars handled before going to a more powerful engine. They just needed the power to match the handling. And the beauty of the BOPR swap is that you can be certain nothing about the handling of the car is going to change. It's like you simply added more power to the existing car, and in a sense that's exactly what you are doing. With a basically stock BOPR that power level is going to be exactly what the car needs. Ranging anywhere from about 135 (or less with some ill advised combinations of parts)up to maybe a bit over 200, the output is going to be well within the car's ability to handle it, giving the car the one ingredient it was lacking and truely making it a joy to experience. Well over 200 is possible as well, but now we're moving into the range of a seriously overpowered machine, requiring the driver to know what he's getting into. In short, it was and remains a beautiful match. True, the Ford is more powerful and that is fine. But instead of starting out in the comfortable range as with the BOPR you start out overpowered. I'm not saying that's a bad thing, but you might not feel real comfortable with the wife or son driving it, or the daughter either. The V6 is fine also, as are the various 4's and supercharger add-ons. With them you start out in the comfort range as well and can sometimes add more power, but there are two or three things that you do not have. First the pizzaz of an 8 cylinder engine, and don't think it doesn't make a difference when you open the hood to show off your handiwork. Secondly and deserving of great and significant attention in the minds of a great many is the aforementioned factory sanction. Third, and certainly subject to debate, is the very flat torque curve of the V8 engine, giving it power across the board and giving you more leeway on your gear changes as well as on final gearing. The fully developed and well trodden path of this swap and ready availability of suitable engines is just icing on the cake, since often for the price of an alternative engine or a rebuild for the original you can not only have the BOPR sitting in the engine bay, but a spare sitting under the workbench. So with this many things to recommend it, there really is no wonder that the BOPR remains the favorite engine choice. And just as this swap was a major challenge and a major performance improvement for the motorheads who did the pioneering work on this swap, the same holds true for the guys doing those other swaps. They are acquiring their own bragging rights, just as we did. Will we be able to keep up with them? Who cares? My car has so much power now I have to be careful who I let drive it. It does everything I ever wanted and more. So I don't concern myself about whether Larry, or Steve, or Dan or someone else is going to be able to outrun me. Maybe, maybe not. What really matters is that I can have all the fun with it I can tolerate, and nothing else is really very relevant. That's why I said earlier, don't start out with more power than you know you want because it'll spoil you. That extra power does cost something, whether in terms of money or downtime, and in the long run what it really costs is fun, time spent in the car, and money that could be spent on other things you'd like to do.

Of course, it doesn't hurt a bit to know that later if you decide you want more power it is only a few not too expensive parts away.

Jim Blackwood

This thread was discussed between 09/10/2005 and 06/11/2005

MG MGB GT V8 Factory Originals Technical index

This thread is from the archive. The Live MG MGB GT V8 Factory Originals Technical BBS is active now.