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MG MGB Technical - crossflow cyl head

HI
I TRIED TO LINK TO THE PREVIOUS DISCUSSION ABOUT CROSSFLOW HEAD BUT COULD NOT.
I HAVE BUILT QUITE A FEW CROSSFLOW ENGINES NOW FOR BOTH THE MGB AND MGA AND I HAVE DYNO SHEETS FOR A NUMBER OF THEM IF ANY BODY IS INTERESTED I CAN FAX THEM THE POWER IS AMAZING USING A PAIR OF 45 DCOES
THE WAY WE HAVE OVER CAME THE WATER VALVE PROBLEM IS BY USING THE TR6 VALVE AND ADAPTOR PART NUMBER 565755 AND 148435.
TO OVERCOME THE DISTRIBUTER PROBLEM USE THE LUMENITION MAGNATRONIC SET UP .
I RUN A CROSSFLOW IN MY OWN MGB WHICH IS FEATURED IN THIS MONTHS MG WORLD MAGAZINE ITS THE YELLOW ONE ON THE FRONT COVER.

CAN ANYONE SHED ANY LIGHT ON MG CROSSFLOW HEADS AND FIA RULES I HAVE HEARD CONFLICTING IDEAS ON THIS I WOULD BE VERY INTERESTED ON ANY INFO?
CHEERS CAMERON
WWW.BRITISHCLASSICCARS.COM
cameron gilmour

sorry
web address WWW.BRITISHCLASSICCARSPARES.COM
CAMERON
cameron gilmour

Cameron
Was there a reason for the MGC bonnet for clearance, from the photos it doesn't look as if it needs it? Was this purely a styling choice?
I think the Roadster looks brilliant without the bumpers.
Martin

MARTIN
THE MGC BONNET IS ALLOY AND LIGHTER AND ALSO I THINK IT LOOKS BETTER THAN A STANDARD BONNET,
THERE IS NO CLEARANCE PROBLEMS WITH THE CROSSFLOW HEAD FITTED THE ENGINE SITS AT THE SAME HEIGHT AS THE STD ENGINE
CAMERON
cameron gilmour

Cameron,

I notice on your site the head is noted as "HRG". Is this a different casting than the "MSX" head made here in the States? IS it a reproduction of the original HRG Derrington Head? If so, how does it differ from the MSX?

Peter
Peter G

Peter, the Derrington comes with 1.69 intake I believe. The MSX starts with the smaller inlet, and in my case, a 7 thou deck warp ( ez fix, with the general workover before implant). Cameron- I've been in a small circle on this Board regarding the x-flow wonders. So glad to widen the coven with you, making 3-4 of us who can testify to the power. My x-flow on the 1971 mgb roadster has been the single best addon I've ever run. I have a dyno at 4500 ' elevation done in Reno Nv last year at 5200 repm, just a smidge over 100 horse. I would kill to get a copy of your "sheets" please and thanx. Do you sell the Derrington? Can you refer me to a supercharger, Roots or otherwise, that'll mate with the x-flow? I have Han's product already, and have ordered his 2.5 header set ( jet-hot coated) which is due off thew boat soon. Just installed 1 1/2 stubstacks and the higher flow rate seems to have smoothed noticeably. V
vem myers

I have a crossflow engine built by Cameron Gilmour which has been in my car for the last two years, the initial dyno readings showed that the engine was producing 180 BHP @ 7000 RPM. Torque readings showed 147 LBS @ 5500 RPM. I ran the car at first with no rev limiter installed but felt that it was safer to fit one as the engine would continue to rev without any signs that it would run out of breath. I have had some great fun showing the local youths that their hot hatches have to be something very special to keep up with my 30 odd year old 'classic'! The intake noise from the Webers took some time to get used to but twinned with the big bore exhaust gave the car a purposeful, unique sound.

Chris
Chris Hardy

when i mention the crossflow it is the msx head i use.
vem/ if you want to e mail me your fax number or your postal address i will gladly send you the dyno sheets i have for the 3 crossflow engines we have the power figures for. i may add that they are all for 1950cc engines.i have heard about the supercharger you are on about but i have never used one. there is an article in feb/march mg world magazine about a magnette with one fitted which i found interesting the owner raves about it.
cameron
cameron gilmour

very interesting
c

Cameron- So you'd be the guy to endorse the 1950 as a solid arrangement and perfectly safe bore ( assuming unshifted core), after all the warnings on flex, oil consumption, power loss, etc. Many have said the increase in power on max overbores is completely out of proportion to the small ( % overall) increase in volume, therefore a real bang- for- the- buck- winner. I'm considering the offset and stroke to 2100 on the next x-flow I build. That is if I can track down that Vortex Super Charger that fits the x-flow.My office fax # is 530-587-1707 ( USA< Truckee Calif.) I will thankyou in advance for the dyno sheets and post them with mine for the 1971 x-flow on the office wall. Do you feel the secret for the unlimited rev potential are those sidedrafts? Have you looked at Han's 2.5 jet hot coated headers from oz. He claims a flat 12 hp increase across the curve. Vic
vem myers

Would a crossflow head be a suitable candidate for EFI instead of webers? I know it's possible to get throttle bodies to fit DCOE manifolds, and a system like: http://www.sdsefi.com/ works very well - a friend of mine uses it on his Toyota 4AGE. I have no connection/experience with them other than helping my friend dial his system in, though I was impressed when I emailed them a few years back about it and rather than lead me on their response was that the system doesn't work well with siamised intake ports like those on a b.

For the really ambitious, there's: http://www.sdsefi.com/ but I think I'd be very worried about burning up a freshly built crossflow engine while I was doing the tuning - I believe the SDS would arrive programmed reasonably close to a suitable fuel curve.
Mike Polan

Oops, for the ambitious the link should have been:
http://autos.groups.yahoo.com/group/megasquirt/
Mike Polan

Apparently the F4 kit from the folks above fits and works on the cross flow, it was revealed to me as dribble exited the left side of my mouth.
vem myers

I am very interested in the possibilities for an EFI crossflow motor. I am personally thinking about building a low compression, prob. 30 over X Flow EFI motor and trying to turbo it. EFI is the way to go for what I want to do. I would rather build a plenum to hook up to the dual DCOE intake, mount a Miata or Focus throttle body onto it and have some bosses drilled for the injectors themselves in the manifold. I was thinking about the Electromotive control system though. Anyone?
Jarrod

Jarrod,

The twin SU manifold would probably be your best bet. You'd have to weld some injector bosses on near the cylinder head face and "port" the area properly. Also it would probably be best to use a twin throttle body arrangement in place of the carbs. With the right port work to the manifold, I see no reason why this would not be an excellent combination.

I'm still not exactly "sold" on the rest of the head...

Sean
Sean Brown

Jarrod, the Electromotive TEC2 and TEC3 units are great. They could be adapted for use with an MG. The whole process is time consuming and requires a laptop PC to develop & program the fuel and timing map. The Electromotive site tells all about their capabilites. BEWARE, This is A LOT OF WORK. It's More than I am honestly capable of without serious help (technical AND psychological).

I bought a (300cfm)TBI Holley Pro-Jection system meant for a six cylinder Jeep. It is supposed to fit a Weber DGV intake manifold. Its adjustments are crude but may suffice.

I know that TWM (twminduction.com) is currently (slowly) developing an EFI conversion for SU carbs, and it should have no problem fitting the crossflow head. They don't know when it might be ready. If I can get this to work I will proudly post its success(or its failure). If someone else has done the TEC2/TEC33 thing or had success with the Holley system, please let me/us know about it. Cheers, O. Jibril (mgb77brg@aol.com)
O. Jibril

You could build your own plenum to fit whatever throttle body you wanted to use, my buddy with the SDS made his own from aluminum, he found a local weld shop with a TIG to put it together for him. You can see pictures here: http://members.rogers.com/m.polan/Gallery/BobsGallery/BobsPics.html

There's a writeup of how he did it on the full site at http://www.7builder.com, check the build diary section for "Bob's Locost Drawings".

The SDS site is very good, you could use it to figure out what features you wanted in an engine management system whether you use their product or not. The SDS EM-4F would be nice with the crossflow, no more fussing with the distributor under the intake - it's not used at all with this system.

Mike Polan

This thread was discussed between 07/01/2003 and 14/01/2003

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