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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 Technical - MGB Turbo Conversions

Has anybody done a turbo conversion. How difficult?? Any pictures of conversion??
ct hester

CT

I've seen a couple. One I have pictures of and uses a cross flow head, which makes for a neat engine bay. Intercooler in front of the rad. You could use throttle bodies this way too. Apparently the guy had trouble keeping head gaskets in in and it now has an engine conversion - Nissan twin cam turbo I think. I would think if you wanted a turbo MGB you'd be better off putting a nissan sr20det in it rather than turbo'ing the B series.

Grant
Grant

http://hometown.aol.com/my73b/

http://hem.passagen.se/larsragnar/index.htm

http://www.geocities.com/gocartmg/
Derek Nicholson

CT,

I have a rover T16 turbo in my BGT, but it would've been much much easier to turbocharge the B-series. The chap with the crossflow (and later nissan motor) is the neatest I've seen so far, I think he melted his B-series bottom end but even if you have to buy forged pistons it's gotta be cheaper than all the custom stuff required to fit a different engine.

What year car do you have?

hth,
--
Olly
Oliver Stephenson

Oliver, does the T16 go in without any body work mods?

The atraction of a turbo or supercharger conversion would seem to be the lack of body mods.

I read about someone fitting a K series and I think they had to mod the bulkhead corners in a similar way to that done on V8 conversions due to the width of the DOHC head. But K is an inclined engine so it may be different for a T16.

I assume your T16 is mated to the 4 sync box.
David Witham

I've had both a turbo and a supercharger (on a 215 Olds engine) and would recommend against the turbo. While it's fine for a straight-line car or FWD, with the RWD MGB the turbo lag will put you into the weeds. Or the wall, or other cars... It's just impossible to accurately predict and the sudden surge breaks the back end loose in the corners. I'd recommend any of the alternatives as being much safer and just as powerful. In fact, for more power the first choice has to be the swap, since the low CR of a blower engine just kills fuel economy.

Jim
Jim Blackwood

David, the short answer is no... it's not major but I have had to make some changes. Plus none of the rover ancilliaries fit into the car anyway, everything had to be home-made. Yep, it's on my beloved 4-sync O/D MGB 'box.

Turbo response just takes a little getting used to, it's totally predictable (unless you have a fault) and no different to having wild cams in any engine that means the torque comes in later... there's just more of that torque when it arrives! Proper boost modulation (not just strong actuator springs and bleed valves as most 'tuners' have to contend with) makes it even more drivable.

That said, the T16 has a nice small turbo and it's all in by 2000rpm. Driving sideways isn't too lethal a passtime.

All fwiw,
--
Olly
Oliver Stephenson

CT,

There was a fellow in Hawaii who did one a few years back using an Austin (Morris) Maria 1.8L manifold. Last I heard from him was about two years ago, probably on this board. He was switching his motor over to a GM 60 degree V6 and was offering his turbo system up for sale. If he did post here, it might be in the archieves.

I think the marina manifold makes a good conversion point because it is a side draft and easier to fit a turbo in that direction and its a single SU rather then the duals of earlier cars. It is a more efficent manifold then the late model ZS manifold of US spec MGBs too.



Jim,

I drove a classic mini a few years ago that the turbo kicked in so early that turbo lag was not bad at all. I think it was just a Metro turbo transplant which would have been 95 BHP out of a 1275cc so not bad power, but not huge power. That would probably be around 120+ in a B series.

I think the supercharger makes more sense to keep heat down though.


-BMC.
BMC Brian McCullough


If you scroll to the bottom of this page you can see the MGB-turbo with crossflow head Grant and Olly previously mentioned, and also at the top of the page you can see the car's current (Nissan CA18DET turbo) engine: http://www.britishv8.org/MG/ToddBudde.htm

Here's another neat turbo-4 MGB, but this time using a 2.3L Ford (Merkur) engine: http://www.britishv8.org/MG/TimOBrien.htm

Also, there's a gentleman here in the Denver Colorado area with an absolutely beautifully executed MGB non-crossflow turbo installation. I'll see if I can get a photo or two uploaded later today. I would've posted them already except (a) I misplaced the gentleman's name and (b) he never sent me the "How It Was Done" article he promised me.

Folks, if you're interested in performance-modified MGB photos the first place you should check out is The British V8 Newsletter. If you have a cool car to show off, you should certainly consider sending us photos and a description for our gallery and newsletter!

At the moment we're also having a photography contest specifically for PERFORMANCE MODIFIED British sports cars. Read about it here: http://www.britishv8.org/Articles/Photo-Contest.htm

Curtis Jacobson


Here's the gent I'm trying to ID and get in touch with: http://www.britishv8.org/Photos/MGBTurbo-A.jpg

His turbo install: http://www.britishv8.org/Photos/MGBTurbo-B.jpg

I didn't drive the car of anything, but I did hear it run. It started easily, sounded great, and responded very quickly when he blipped the throttle.
Curtis Jacobson

I've seen a Cosworth turbo transplant into a MG Roadster 150 + top end and 0-60 in around 4.5 secs. Was interested in doing one myself but the French have some strange laws about getting non standard cars registered.

John
John

I would think that with the MOSS fuel injection system, there would be a number of turbo's that would work. I recently drove a PT Cruiser with Turbo. Turbo unit was a smaller unit but gave the car a nice power boost.

You then could also look at one of the rear mounted turbo units. There is more than enough room under our MGB's to mount one of these.
BEC Cunha

I am working right now on my second Turbo B and i am really happy with my results, it is a blow through 38/38 right now, my first version was using a 32/36.

almost all parts utilized were used or second hand and no more than 8 psi. never a problem with the internal components of the engine.
iam using a turbo from a 900 Saab.
a delight to drive.
If you need more data let me know and i can help you on your conversion.
sorry, i have pictures but i dont know how to attach to this page
Luis Rodriguez

Luis,

Are you using standard MGB pistons? If so are they from the low compression 8.0:1 version or the high compression 8.8:1 version.
David Witham

I seem to recall a chap called Nathan from Nottingham on here that used a Metro A series T/c unit on his B series.

Having a supercharged car, I'd agree on the comments re compression.
Martin ZT

8.8 cr is no problem if the engine is tuned correctly and boost not over 7.5lb. Mine has done close to 20000miles with the SC and had done over 60000 before fitting. Still goes great, no fumes, no oil leaks and no overheat.
Denis












DENIS H

Im using the stock pistons from my 1979 B, i think they are the low version but 8.8 is also OK on the conversion, remember that you have to retard and/or limit total timing advance and also you have to use high octane(premium) fuel and re-jets the carburator.
Luis Rodriguez

A fellow club member built this one. MGB engine, Ford Escort turbo, Harley CV carb. There was a write-up about it in one of the defunct MG mgazines.

http://www.britcars.net/Seats1.html
Carl Floyd

The MGOC and Abingdon Classics advertised a turbo conversion in the early 80's on unsold MGB stock under the "SEC" Special Edition Classic banner. At least one turbo was produced and entered Concours events in the mid 80's in the UK. It was an Inca Yellow GT and my fading memory recalls a brown vinyl roof and leather interior, though that may be inaccurate. It would have been probably a W plater.
D Wellings

Thanks everybody for the info. Luis could you send some pics to 'hesterdesigns@westnet.com.au' i would love to see your conversion... thanks
Carl

I have no problem with turbos, indeed apart from my SC B our three other vehicles are turbo. The problem I see is with the B design in reguard to fitting a turbo. The formula for air flow in cooling is to have twice the area for the air to exit after passing through the cooling, be it a radiator or air cooling, as the entry. A B does not have a lot of open space at the rear of the engine and I can see problems in this reguard. You need more exit area because of the sudden expansion of the cooling air as it is heated first by the rad, then the hot engine and exhaust.
A Turbo will make the air even hotter so there is more of it in volume to restricting the system.
These problems may well be addressed with ducting, leuvers or some other idea but the problem is to get the "hot air out" so the cool air will flow.
Denis
DENIS H

IIRC, when the last B's were built, someone bought a bunch in the UK and installed a turbo kit. The effort was reasonably researched and engineered. Does anyone have pictures or knowledge of these cars?

Re the Moss fuel injector unit, this is a simple, single point throttle body injector unit, similar to or based on early GM units. They are meant to be an alternative to Z-S carbs. They should not be confused with more modern multipoint injectors, which are installed in manifolds just before the charge dives into the head. This multipoint system is ideal for turbocharging, as all the spooling, compression, intercooling, etc. is done without gas/petrol. The Moss FI unit, well, it replaces the Z-S.
John Z

See my earlier post re the SEC MGB's. Martin Bentley at MGOC should recall the details.
D Wellings


http://www.mgcars.org.uk/pics/polroid1.jpg

http://www.mgcars.org.uk/pics/richmg5.jpg

http://www.mgcars.org.uk/pics/rbwmgbl1.jpg

http://www.mgcars.org.uk/pics/rbw91.jpg

This is a car that Rich Wasman built in the late 90's. It was a very well done conversion and ran like stink. I own it now, although it is currently sans turbo. I still have the turbo hat used on the blow-through Weber 40/40 shown in the richmg5 pic if anyone is interested.

I'm about to pull the engine and 5 speed and replace it with a 3.9 Rover. The drivetrain has less than 30K on it from the complete and pricey rebuild Rich did.

Here's the text associated with the photos from the BBS.

" Rich Wasman's Turbo GT
Take a look at that 175HP engine.
Update August 1997: The car has now been rebuilt again without the Turbo. It is air conditioned, has a five speed Nissan 280 ZX trans, heavy duty lowered springs, tube shocks, negative camber "A" frames, urethane bushings, HD front and rear sway bars, Mini Lite wheels with new 205r60x14 Kuhmo H rated tires, electronic ignition, Jacobs boost retard timing controller, racing seat belts, factory design front air dam, painted bumpers, tinted glass. The engine is stock except for ported and polished head and Crane cam(very mild, chose because this is a new not reground cam) and valve train, roller rockers, high tensile head studs, high volume oil pump, baffled oil pan, SK 45mm side draft carb, 3 into 1 header. I performed all work including the black lacquer paint(except for machine work on block and head). The engine has less than 2000 mi. On a recent trip of 260 mi. I got 27 mpg running the A/C."


David Gable

David, if I may ask you a question?
-Why did you choose to leave the turbo off after the rebuild?
I can understand the swap to the 3.9, that's obvious, especially after having the power level at 175hp. But why the non-turbo engine? I'm sure there must have been a good reason, could you enlighten me?

Jim
Jim Blackwood

Hello Jim. Rich is a gearhead and this was his first and only MG. He was a national class drag racer and the best engine builder and painter I have ever known. He removed the turbo before I bought the car because he went through a couple of pistons and decided to just go back to NA rather than install forged. He was using Hepolite cast 8.75 pistons and usually ran between 7 and 10 PSI which should have been no problem especially with the Jacobs timing retard and the air-fuel meter he installed. However,he liked to run foot-to-the floor a lot, sometimes with the boost cranked up, and it was just too much for the cast slugs to cope with. I was around while he tried various carbs/intakes and can say that the car ran best with the blow-through Weber down draft.
David Gable

Didn't janspeed have a kit for the B-series in the 80's?
N.C. Nielsen

I purchased Rich's turbo parts several years ago. I have also fabricated several set ups of my own. After spending SEVERAL years and more money than I can count I never got close to the 175 HP mark. Forged pistons, wedge crank, cross flow head, stainless valves, roller rockers, gt28 turbo, aftermarket EFI system and hours on the dyno. Even on its best day with 13 psi of boost it only got to 160 HP. I would NEVER run 13 psi of boost on the street. Well I did when a faultly wastegate controler allowed 18 psi and caused terminal detonation. If I had to put a number on a 5 port carb/turbo setup I would put it around 125 to 130 even with the boost around 10 psi. I have found some recent info on the web/ebay that may create some new intrest in B turbo engine. There is a diesel version of the B engine out there, and we all know diesels are high compression beasts. Im wondering what they have done to the short block... Might be worth picking up one of these blocks and taking another whack at the setup. Id be intrested in going after as 5 port setup. Would be a EFI type setup with a throttle body injection system. I think the electronics are the key to extracting anything more than 130 HP.
Todd Budde

Perhaps a little competition is in order? Lowest-budget 150-horse turbo B-series? When I've cleared my current (non-MG) engine rebuild project out of the garage, maybe I'll see what I can come up with in a weekend...

Todd, I think the BMC 1800 diesel bottom end was just rods and pistons (and I'm not even that sure about the rods). They were very conservatively rated engines so they didn't need excessive engineering. They probably had the steel crank that was available in some petrol Bs around that time - I have a rusty one of these 'in stock' somewhere :o)

ttfn,
--
Olly

Oliver Stephenson

I was interested in the same lines of turbo/supercharging
but it seems to make sence that you would slap a supercharger on the b series rather than cut appart the exhaust and such to try to wangle a turbine in there-

i dont understand why not cut the faff and bolt on a charger that way you have constant boost- ontop of that it would be much easier and quicker not to mension probibly cheaper-

image that a set of 45's, chamber to blower- you dont even need to worry about an intercooler-

turbocharging it such a lash up. Im not saying if i was offered one id not have a play but for the amount of work? SUPERCHARGING- KIS-

anyways dont think my comment will go down that well, hay ho...

seb
SGE Granville

Hi Seb,

Using a belt-driven supercharger is always an option, and there are 'kits' out there that will probably bolt straight on. They are expensive though!

If you had to do it all yourself, which is always the most fun, I think you'd find both systems vying for which is the most simple. Blower belts have to transmit at lot of power, which means changing over to a poly-V belt and automatic tensioner. Poly-V belts are hard to make work! Intercooling is just as neccesary as with a turbocharger - there's no magic to it, and in fact centrifugal compressors (whether belt or exhaust turbine driven) are more efficient than positive displacement ones.

Are you up for the competition? Make 150 crank horsepower, keep the reciepts for the parts and let us know how you did it :oD

--
Olly
Oliver Stephenson

150bhp? at the crank? make it at the wheels and itl be harder to do!
humm im game but it will be a while, but i can give you a small set of clues... stage 3 head, fullflow exhaust, 45 webers, pipercam rally, performance coil, uprated plugs and leads and a drop of i dont know how much weight..

and i have unfortunatly came short,and fitted a nitrous kit, not really keeping it traditional and old school i know but it should be interesting...the cars coming out soon though from 9 months in the shed...
il eat my words if it does not start..
viva la b
seb
SGE Granville

You may want to take a look at this setup. Turbo without a major modification to the exhaust system.

http://thunderracing.com/catalog/?action=vshop&vid=4&pcid=259
BEC Cunha

$3795.00! For a setup where almost every key feature is a load of... how you say... baloney?

They lose the competition :o)

--
Olly
Oliver Stephenson

umm 3795 sounds like a good idea i mean its only say 2 grand? i mean as a ruff guide, so your still spending over the odds- o and from what i can gather you lash it up on the end of your tail pipe?
good idea yeah il stick to the supercharger...the other thing is um how much space do you really want to save in a b's engine bay? id like to fill it personally-

yeah i think moss have the answer....
SGE Granville

What they dont ever talk about on those rear mounted systems is turbo lag. ALL you will ever get out of them is "MINIMAL LAG" Look at all the plumbing thats there. We do deal with some in the inter cooling process however intercooling is NOT underated. Look HERE http://www.turbofast.com.au/javacalc.html run a few of the caculations you will see the dramatic effects intercooling provides. NOT to mention it makes BIG improvements on detonation as well as charge air temps that ALL go back to how much boost you can force down the motot. Doesnt matter how big or small the turbo is if the engine wont take it than its all a moot point. Im pretty sure a well built short block, the right cam, good head work, proper turbo and fuel setups that 160 RWHP is possible. Im sure even more than that. But I would have to say the costs ar ein excess of 15K. Im pretty sure the block and head work alone would be around 7K then to add all that outside... WHY for 5 or 6 you can have ONE hell of a V8 or even a K series.. Better yet toss a japanese engine in there. you can have yourself 300 rwhp not a problem. If nostalgia and BIG HP are what you are after the B engine is not the place! I dont know of to many people out there willing to dump that kind of cash into a B with SO little gain. Not to mention once you get there the chassis improvements you NEED. Were talking about a 20 to 30K ordeal once you get there. Might as well buy a porsche! Trust me here!! This is all FIRST HAND knowlage.. I couldnt even get 10K out of my car now as it sits and its a beast! Drives like a dream with modern power and suspension. Pure enjoyment is ALL that comes from a machine like that.
Todd Budde

This thread was discussed between 19/01/2007 and 05/02/2007

MG MGB Technical index

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