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MG MGB Technical - Cross Flow

Well, after much wrangling my old MGB has a new heart. MSX headed and cammed, it finally came back to life in the fog/rain Thursday night at about 10:00. First drive was Friday after some surgery on the Webers' auxilliary venturis and a lot of minor fiddling about. Used the jets, etc. recommended by Pierce, but the car runs way too rich. Gotta do some more homework. I like the Pierce cam so far. Good bottom end and wants to rev. After a proper bedding in period we'll see what it can do. I used an evacupan because I did not like the idea of one intake port providing the crankcase ventilation. I had a junk yard air pump pipe plumbed into the exhaust pipe behind the collector. Both bits are stainless so a bit of TIG welding fixed me right up. Still early in the game but so far I'm pretty impressed with the engine's power and sound. The old '66 has taken on a new personality. Now if I can find a way to tone down the intake growl just a bit! An early overdrive was rebuilt and installed as well, but there is a small glitch with it that has to be worked out before I can do much more.
David

Something is happening but I don't know what it is. I have been interested in these X-flow heads for a couple of years now but have yet to install one. What are you running - a pair of DCOE 40s or 45s? What are the specs on this Pierce cam you refer to? Also: What is an evacupan and why would you add an air pump to a car which didn't have one in the first place? And speaking of X's, - merry X-mas.
Marvin Deupree

Gentlemen;
If David will let me put in my $.25. It is very important that an engine has a crankcase vent system. Early cars just used a pipe down close to the ground which when driven created a suction which pulled fresh air into the oil cap and out the venuri at road level. Davids method uses a venturi in the exhaust pipe which creates a vacumn which pulls the crank case gases out. It is very important to have this done or moisture-acids etc will build in the crankcase. The Weber set up as well as early HS 6 setups have no provision for this venting thus something else must be arranged. Bob
Bob Thompson

David-
You have my heartfelt sympathy. Zeroing in a pair of Weber DCOEs is a daunting task. Do you have access to a dynometer?
Steve S.

David- I've been running the x-flow for nearly a year. After startup, I came onto this board and blathered about the tremendous gain lo-mid-hi end that the MSX provided ( "Amazing X-flow": Archives 2001). I nearly fell over at the dunning. No one, not a single post had a pleasant word for the setup. The Right Revrend P. Burgess weighed in with his eulogy. Then the thread morphed into a remote oil filter discussion to my surprise. All in all, I felt I'd made a terrible, expense, huge mistake. I waited for my lovingly built 60 over flattop AE (10:1), Jackson 1:55 rollers, Elgin .015 cam ( spec similar to the Piper 270), Aldon stage 2, Peco, K&N, all in front of the Ford Sierra 5-speed ( which is another success story for another time) to blow, self destruct, fail, or some damn thing just as I'd been warned.
Well, I asked in a new thread for any testimonials on the x-flow. Not a single response. I wondered if anybody was out ther to speak to me of personal experience. Nothing.I will share with you one man's happy story: D-man, you have acquired some great potential in my opinion. Out of the box my unit was 7 thou warped. We 3-angled, equalized volumes slightly ( within a cc or so) and decked her 10. I struggled with the torgue number and went with Burgess' recommended 45. Since I've retorgued 3 times to 50. I live in truckee at the base of Donner Lake, 6400 feet elev. After breakin and a few 100 mile short runs, I took her up to Donner Summit: 7300 feet in 12 horizontal miles from D Lake. Ran her into 5th, and proceeded thereafter without a downshift to the summit. At 80-85, fifth gear, pedal half way, 20 percent grades for some stretches, I could pull like a freight train at will- stayed at 3500-4200 without breaking a sweat. Too sweet. In Reno, a month later, it dynoed a smidge over 100 horse at 5200 RPM. SInce I've chatted with Burgess, Rog, and enjoyed scholarly discourse with the eloquent, Mr Bigface, in Viginny ( SteveS). You and me are the only guys out there from the hear and see on the boards. We need to keep in touch. Steve is trying to source a Derrington for his next project and we'll have 3 of us in our coven. For what its worth, I've since used Peter's Fast Road Head on an identical rebuild, otherwise, and he is right that on mid-hi to hi end, his cast work approaches the apparent flow of the x-flow. But at the low-mid, the x is so much more I would definitely do it again. Heaven might be a Derrington x-flow, reworked by Burgess to the higher Fast Road or Ralley level. I believe SteveS is planning a trip up there next rebuid. Any questions or HO, shoot me an "E". Merry X-mas, Vic
vem myers

I'll post more on the particulars later, but first a couple of quickie questions for Vem. What carbs did you use? You state that you had to re-torque several times. Did you end up with a leaking gasket? BTW, Moss states that mine was only the 42nd cross-flow head that they have sold. I'll bet that Pierce hasn't made more than 100.
David

David-Originally had HS6 planned, but lo-bucks had me screwing on a set of rebushed HS4. I'm toying with the Weber DGV as we speak for grins. I retorgued out of anal fear. As I said, I was stunned at the board response, and was determined to do all possible to keep the head and gasket mated in bliss. Each retorgue, after backing off 1/4 turn, reset the ARP nuts a little deeper.No, not a leak or weep ( I used Lawrie Alexander's trick of thin copper stran wire set in LIGHT smear of silicone on outside of waterjacket holes between 2 and 3).
Well, D-man, we are pioneers then. I'd like to hear from 40 other guys though. I'll not forget Master Brown's comment on the MSX after his dunning: " ....but in their favor, it does appear the manufacturer has spent money on a very attractively packaged and photographed product" ( or sum such).Vic
vem myers

Vern: let us know how the DGV experiment turns out. I wouldn't expect any improvement over dual HS4s even if you use a sync-link on the Weber to open both barrels simultaneously. In fact I would expect the SUs to be better in a crossflow setup since they are semi-sidedrafts with a straighter shot into the ports. You could also use cold air induction for even more power with the SUs- something you can't do with the Weber due to clearance problems. Of course all of this is conjecture on my part. I look forward to hearing more real world reports from you and David. As you noted there has been a real dearth of acquired B series crossflow knowledge and your posts are much appreciated.
Terry

Terry- I stumbled on a rebuilt Web and manifold at the bone yard a while back. It is like new and for the $50, I thought I'd play with it a tad. I'll keep you and all posted. Maybe like in the song "Alice's Restaurant", me and D-man can start a movement for the advancement of x-flow knowledge. Vic
vem myers

To Date the Weber seems to be "faster", more snap. I haven't wound her out to 7k so have no feel for the high end delivery. So far, to my surprise after balancing HS for 30 years, the webbies seem solid, consistent, and up to 5400 RPM, seem to deliver without a hickup. Vic
vem myers

Vic: thanks for the info. What jets are you using on the Weber? Is it still in progressive mode or have you rigged the linkage for simultaneous opening? Also the crossflow Weber DGV intake manifold looks rather awkward- did you modify it to improve flow? What I'm getting at is you notice an improvement right away and if you haven't done any mods or rejetted it yet there are certainly more gains to to be had. Keep us posted.
Terry

Terry- If you'd like, give me a scream on my e-mail so we don't monopolize and piss-off the uninterested others regarding the x-flows.

Don't have a clue on jets or needles. I screwed this on the car after finding the setup, in new looking condition in a Sacotomato Bone Yard. I examined, cleaned-up a bit, and pronounced them good to go. It was clear someone had just completely rebuilt the unit. I thought what the hell, lets have a go of it. I've ordered the tune kits, and will report best setup at this 6400 foot altitude. The lingage is stock progressive. I talked to Sean Brown about port/polishing manifolds. Turns out, in his opinion ( and that's plenty good enuf 4 me) the manifolds for the HS6 and Webbs, both stock and x-flow, are nightmares of oppossing turbulences and flows. So, at this time I'm just going with what I got....a new experience as I usually fiddle with things till they beg for mercy. Oh Well. Happy x-flow New Year. Vic
vem myers

Please don't take it off-board. I, for one, am very interested in as much first-hand x-flow info as I can get.

When I get to daydreaming, I'm thinking of a supercharged, cross-flowed, TBI B. Let's see what the old B-block can REALLY do.
Baxter

Ditto, Baxter. Uninterested parties will bypass the thread.
Marvin Deupree

Vic, I talked to Bob this AM. My car is at his shop in N.C. He still doesn't have my OD problem sorted so I don't know when I'll be able to collect it. It is shifting into OD by itself, even with no power going to the solenoid, so there is a valving problem. He has put about 30 miles on it, and I drove it about 10 myself before I had to come back home to Jacksonville before Christmas. I'll be very happy to get it home and start sorting out the carbs. Keep all of us posted on your 32/36 project! I'm glad to see that you, Baxter, Terry, Marvin and, of course, Bob and Steve are interested in these heads. Several years ago I tried, without success, to get 8 people together to buy MSX's from Mike Pierce at a substantial savings over retail. I got a total of 1 taker. There has been so little interest! When I was a teenager in the seventies, Derrington cross-flows were the holy grail in MGA/B circles. Now that x-flows are available.....nada. And where are the other owners of these things? A fellow in our local MG club has an MSX head on his B, but I have not driven it, and Bob Thompson saw one on a car at a show. Other than you, Vic, that's about it that I know of. No web page, no reports from Moss and Vicky Brit who, lord knows, ought to print a success story or two to try and jump-start their sales. The only thing I have ever seen in print is the Grassroots Motorsports article on Mike's own car. Just as you did Vic, I spent more than a bit of money on a leap of faith. It sure looks fast, though!
David

Hiya David

We are suprised the X-flow head hasn't taken off...I guess we have modified around 10 or so of the MSX heads, and we do a fair amount of the heads for some of the 'big players' over here. I guess people don't want to take the plunge with all the costs involved, I suppose it depends how much you want more ooooomph! in your engine?

Moss have brought out a TR4 ally head, which is starting to sell in fairly large numbers...we have already worked on more of these than x-flow Bs....however, the core for a cast iron TR4 head is worth upwards of £300 GBP. The cores are very good too, they have been thickened in all the areas where people want to mod 'em and where they used to display a weakness.

The Healey four and six heads in ally don't seem to be selling as fast as one would imagine either....and thats with a BJ8 six head core being around £350 GBP and the 4 cylinder core being very, very difficult to source.

I get the feeling that the ally heads would sell better if the profit margins were not as high? Most of the ally heads we do are to improve the flow of the 'as sold' product.

What sort of price did you get quoted for ten off...and what about manifolding(intake header?)? I would be interested in joing in with a group purchase.....maybe one or two castings?

Peter

Peter Burgess

Please keep this discussion on line as I am quite interested to hear of the succes (or failure) of the cross flow head. It would seem to be a common understanding that the head is the worst part of the B series, so the idea of an alternate design is exciting. At present they are pricey and seem to need further work after purchase, so that does not make one want to rush out and buy, but if the performance is significant it might be worthwhile.

A couple of questions to those who have a x-flow head:
1) What about the heater valve connection? I haven't seen where it connects to this head. 2) Comments on the clearance problems to dynamo/alternator and distributor. Is this a problem?

Peter
Peter

Peter-
Neither the Pierce and the HRG Derrington crossflow designs has provision for mounting the OE Heater Valve. However, this drawback can be overcome by simply installing a threaded "L" tube into the water port in the head beneath #3 Intake Port on the HRG Derrington head or in the water port on the rear of the Pierce head, and running a hose to an MGC heater valve (Victoria British Part#2-378) mounted with its
bracket (Victoria British Part# 12-4808) on the heater box, just like an MGC. The right hand spigot (as seen from the front) of the heater core will need to be shortened to mount the heater valve onto the heater box. An MGC heater cable (Victoria British Part# 6-7985) can then be run from the dashboard control knob. All other factors being equal, an unmodified HRG Derrington head produces 15% more power @ 3,000RPM than that of an unmodified cast iron 5 Port early
18V head (1.625" intake valve). Once the head has been fully modified the Second Generation version of the HRG Derrington crossflow head produces 40% more power @ 3,000RPM than that of an unmodified cast iron 5 Port early 18V head (1.625" intake valve). In as-cast condition, its high-RPM flow is roughly equal to
that of a fully reworked 5-port head. Reworking of the head by a professional yields proportional improvements in power output directly comparable to those of a stock head reworked in the same manner without sacrificing any of it's advantage in midrange torque production. Dual Weber DCOE 45 carburetors
seem to meet its needs best, probably as a result of the plethora of jets available for them.

Yes, the carburetors will overhang the distributor, so conversion to eliminate the contact breaker points is advisable. Also, removing the oil filter will be a
memorable experience, requiring removal of the air filters and their boxes, the carburetors, and the intake manifolds. While this might prompt thoughts of
converting to a downward-hanging oil filter from a Morris Marina, unfortunately, that stubby oil filter just doesn't have the flow capacity required for such an engine. It would actually restrict the oil flow. Instead, a remote oil filter similar to that used in an MGB GT V8 would be quite adequate. This will require the installation of a simple spin-on bypass cover with 1/2" NPT threads (Summit Racing Part# TRD-1013) in place of the oil filter and a single remote oilfilter bracket with 1/2" NPT threads (Summit Racing Part# TRD-1045). This will allow you to conveniently continue to use your choice of standard MGB oil filters. Summit Racing has a their website http://www.summitracing.com/ . Special oil lines will have to be custom-fabricated. Due to the extra stresses on load-bearing surfaces resulting from the increased power output that is possible with this modification, the installation of both a higher-pressure oil pump and a matching relief valve spring is advisable to protect the bearings from the increased pounding.

Steve S.

First time on this board and I thought I would start with my introduction about the SuperB. My car is a restoration of a 1962 roadster with a cross-flow head and a Supercharger. Unfortunately the Supercharger was stolen and is the biggest problem in the restoration. For those of you interested in the cross-flow/Supercharger technology, I have attempted to attach a link of pictures, including the engine before the blower went missing.
<http://groups.msn.com/WinnipegSportsCarClub/mgbghost.msnw?Page=1>

MGAdams
MGAdams

WOW!

MGAdams, that looks simply stunning!!!
Thanks for the link to the magnificent pictures!!! (it works if you copy&paste it and remove the '<' and '>' )

Peter, Steve, Vic, ...
Do you have an idea of the difference in power delivery between a 60s Derrington (as I have, waiting for me to send it to Peter) and a 2nd generation example, when both have been modified?

Next question: what kind of linkage would be the one to get for someone that'll use twin webers?

Another one: will air filters that are 3"1/4 deep fit? And if they do, what length of ram pipes should I install?

Looking forward to reading more on this subject,

Alexander
Alexander M

Peter/Alexander- SteveS ( AKA Monsignor Big Face) provided considerable assistence to me after my x-flow startup, and herein, once again, he gets to the bottom line with the parts references and hot links. A few notes from my hands-on: The heater line to box was aq straight run off a threaded nipple back of head, no valve. I keep the flaps down, mag cover on, and defroster rolled up when I don't want any heat for the very few days a year in August. Peter B.- I'm in for one, and If SteveS hasn't secured his Derrington, he might be another....That's 5 then, let's see what happens. ( Peter, if this flies, I want mine shipped to you upon group purchase for a "Fast Road" makeover please)Peter (NC)- The alternator overhang is no big thing, there were no mods I recall, except a clip-fast spade connector on the temp sender. The dizzy is a PIA fur sur. I had an Aldon Stage 2 rebuild with a Petronix conversion. Also found it possible to do timing by carefully reaching behind the cross flow intake backside to get a hand on the dizzy.You can come in front, under the alt, between the belts if you don't tend to cramp-up ezlee. I modified the dizzy mount plate with a 7/16 hex bolt and to loosen, I pull the dipstick, and use an offset, long box end. Works ok, but is tedious.I ran her about 300 miles, then with SteveS reference, purchased the remote oil filter kit from Summit ( $50 +/-). R/R is a 30 minute job. The trick is to take off the air filters then remove the x-flow manifold at the head, just 4 bolts, and roll off and lay the whole enchilada ( carbs, heat shield,manifold) on the valve cover like a new born baby. I chose the dual oil filter version and mounted the base manifold in front of the radiator. Made up wing nut/lock washer attach so I can unscrew the base and elevate the filters for drain and capture on oil change, then quickly replace the unit after. I take the used second filter and reuse in front, and put a new filter in #2.I wondered aloud to Peter B some time ago about a ram chrge effect on the HS x-flow intake manifold, almost 4 straight inches from carb to head. In the meanwhile I did install 1 1/2 inch stub stacks under the K & N's : the idle seemed unaffected, but the sound of the runup was changed from a growl to a moan, and felt smoother. Alexander-Yes the big 3 inch K & N,s just barely fit, and the one piece top plate is a godsend. You need to replace the fusebox and coil. As I was using a telescoping bonnet strut, I'd moved the fuse box down years ago. I put the new 40k volt coil where the windscreen washer bottle used to go. FYI- I cut the pheno-spacers down 3/8 inch, and used a new heatshield to utilize stock linkage setup for the HS carbs. On the new heat shield, I had to slice out an approximate 3/8" wide by 3.75" long rectangle to clear the accl. cable movement. I had custom cables (+/- 12 inches longer) made for the accelerator and choke ( at a bicycle shop for $12 each)and had the original look and function good to go, albeit on the other side of the engine bay. I've ordered a set of jet hot coated 2.5 inch diameter headers for the vacant driver's side from Hans Pedersen http://www.hi-flow.com/. I will admit the setup is really lop-sided looking. Hey-like the song says: "She may be ugly, but she sure can cook". Happy New Year All. Vic
vem myers

I have nothing to add. I'm just trying to keep this from falling off the page, since it was starting to get close to the bottom, and hoping somebody else can post something worthwhile.
MMD

Just reread my last post- didn't mean to imply that what has been said so far wasn't worthwhile; just thought that there might be more to come.
Oh, and a happy and prosperous '03 to all; may your oil leaks be slow and non-critical.
I have found this BB to be an informative and enjoyable resource over the past year, thanks to you all.
Type to you next year.
MMD

LOL, I have to agree with MMD, I'd like to see the information from this thread keep on coming. Here's a question that might kick it up: I was wondering, with the power increase of the mga twin cam over the base engine, was there ever a thought when designing the MGB ali cross flow to make it a twin cam head? Would we have seen a similar performance increase on the B block?
Mike Polan

MMD- Great motivation. I am now looking around for any type of SC to possibly adapt to the cross flow setup.MG Adams above, has some great pictures to see. Vic
vem myers

Hmmm... Crossflow heads.... My motor wouldnt be posible without one. I have nothing but excelent things to say about it.. One problem I did encounter is working on the dizzy. The ECU in my car controls the timing so its not a realy big issue. But none the less cap changes are hard. The oil filter problem solved itself in a way. I swaped the O/D trans for a t-5 from a 280ZX turbo using a rivergate kit. As a result of the swap it made the need for a gear reduction starter thus clearing the way for a downturned filter from a early car. I do like this way of changing the filter much better.


Todd
Todd Budde

I have a few photos of my engine at



www.frii.com/~neonist

Please give me some feed back other than the lack of content on the web page.. It is actualy moving to a new home and getting a whole new look. I should have some new photos of the new paint job, interior progress, redesigned IRS, and as of course the turbo and intake.


Todd

Todd Budde

Todd- I got locked out, couldn't get the jpegs revealed for the engine. I would be hugely interested in your innovations after the MSX. I'm not familiar with some of the induction names you were listing. Vic
vem myers

Todd:

Very nice work. I believe I saw the rear some time ago; always wondered how it worked out. Is the rear from the same car as the T5 tranny? What kind of roadblocks have you run into with the IRS? I assume you designed it as a bolt in subframe and not as the rear section of a tube frame car.

I have bookmarked your site for further updates.

Pete
Pete

Holy Mackinaw, Todd. That is quite a piece of work; what inspired this particular approach? Is it on the road yet?
Marvin Deupree

Mr. David is coming Monday pm to pick it up so I feel sure there will be much further discusion. It does move. Bob/International Auto
Bob Thompson

David- Keep us posted please. I'd like to hear your testimonial anyway it goes. Vic
vem myers

This thread was discussed between 22/12/2002 and 05/01/2003

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