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MG MGB GT V8 Factory Originals Technical - rubber/chrome front x member

I know there is a difference in car hight rubber bumper v chrome bumper but my question is, is there a different front cross member used on each car. I am interested in the thickness of the cross member. I have a chrome bumper car and the v-8 front oil pan just clears the cross member. I would like for the engine to go down further but no way unless the rubber bumper member is thinner for want of a better word and would allow the engine to go lower.
Richard Porter

the steering columns are different. as well as the steering racks.

The rubber bumber x member's mounting flanges to frame are taller. so, yes, that should give you something like 1 1/2 inches more clearance.

So, what kind of v8? if it's a Rover, try switching to the AC motor mounts. They put the engine back as well as sligthly lower. (Of course this will force changes to driveshaft lenght and exhaust system, but then you aren't going to get that change for free).
Richard Morris

Any clearance is enough. The correct pucks for the V8 are much harder than the 4 cyl version and are much less likely to shift or squash. 1/4" is all the clearance you need. More is always better, but what do you need it for?

Since you are going to have to weld in the motor mounts, you have some latitude in their placement and this may help. Shims can give you a bit more room as well.
jimbb88

Rover SD1 engine with TR7 5 speed. I wanted the engine low enought to clear a Holly and Aircleaner under the hood without a hood bulge but no way with the current set up Wheatly welded in motor mounts and pucks if that is what they are called. Now leaning toward doing fuel injection from Towery which may solve the clearance problem. Engine is already back as far as possible and still have the heater box and I have borgeson u-joints to solve the steering issues. I really want the car to not look modified.
Richard Porter

Some members revert to the chrome bumper cross member to regain spring length and solve other problems. I would like to do this one day.

Unless essential, stick with the chrome bumper cross member.
Ian Buckley

Go and buy some uprated front springs and some
The ones they use to convert rubber bumper ride height to chrome bumper ride height. This is what I did for my now ex- rubber bumper car.
They were $110 . Then go buy some rubber bumper crossmember bolts.
Then make up some one or 1.5 inch blocks to go between the rails and the crossmember. Just cut off some stock 1.5 inch aluminium bar, or some 1.5inch thick steel box sections.
Essentially, turn your chrome bumper cross member into a rubber bumper one.
You will have to shim/adjust the angle of your steering rack of course, but thats easy. You can buy shimms for this for not very much.

This will get you uprated front springs (which improve handling) and the room you need. The small change in camber is also supposed to be a good thing, race drivers often do this deliberatly. It is supposed to improve handling in corners, more rubber on the road.

That should be cheap and easy to do.

However, the next problem you'll encounter is the room between the rails.
Engine plus brackets plus rubber mounts has to fit between the rails, and the engine gets wider further up the "V". I've squeezed mine as low and as tight as I can go and there is still plenty of clearance between the range rover sump and the crossmember. Also between the steering rack and the neck of the "Rover SD1" harmonic balancer (another potential point of contact)

If local regulations allow you to, you might consider mounting your engine down on the crossmember rather than the chasis rails. I read one one person who did this very sucessfully. A lower centre of gravity is a plus. Also it would be much easier to get the engine in and out because the drivers side chasis bracket has to cope with having the steering shaft going through it as well as the engine mount bolt. It gets very tight in there.
Peter Sherman

I've seen a solution to this problem which involved "modifying" the X member by removing the top centre section and repositioning it lower down, after adding some re-enforcement to the "inside". After all the X member is only a glorified box, although a fairly strong one, to hang the steering and suspension on! If yours is as corroded as most of them, it will probably end up stronger, anyway.
Allan Reeling

Hi Richard.

I am running an SD1 pan on my EFI car with no clearance problems at all. I think I could lower my engine a full 1.5 inches if I needed to but other things may cause problems like steering and exhaust clearance. I would recomend the EFI.
M Mallaby

Good to hear, clearance plus relativly modern fuel system makes EFI attractive. Did you buy from Glen or other source for setup. I do have the SUs from the SD1 and a factory intake manifold but unable to obtain V-8 linkage. All must have been thrown away a long time ago. Really did not like idea of converting chrome setup to rubber bumper and then adjusting the hight back down.
Dick Porter

I have used C/B cross member with ALL of my cars. I take out the R/B cross & put IN C/B cross members. C/B cross member you have to set the motor back 1 1/2 inch to get the oil pan behind the stearing rack. I make up motor mts. that lower the motor .400 in. What stops me from going lower is the bottom of the oil pump base & the rack. Dick, if you need info CALL ME! I no can type!!!!! 302-734-1243 Glenn
Glenn Towery

My EFI is a US spec SD1 manifold and plenum. I grafted the 14CUX components to fit that intake. It involved boring the injector bores out to 11mm and a few custom made adaptors to reposition the ICV to the front of the engine and convert from the large TPS to the small one. The SD1 manifold is lower than the stock 3.9 RR. The runners on the SD1 manifold are shorter but smaller than the RR so the air velocity is about the same. Hindsight being 20/20 it may have been easier to simply machine down the RR manifold exept that in California I needed to keep the water heated intake part of the plenum that is normally lost when the 3.9 systems are modified.
M Mallaby

There are ways to cut other parts were you can leave the hot water for the intake & get it all under the stock hood, BUT I found it is easer not to live in Cal!
Glenn Towery



http://www.britishv8.org/Articles/Rover-Hot-Wire-EFI.htm

http://www.britishv8.org/Articles/Rover-14CUX-EFI.htm

http://www.britishv8.org/British-V8-Current-Issue.htm

Peter

This thread was discussed between 29/10/2007 and 08/11/2007

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