MG Sports Cars

I’ll admit, though I do understand what “bump steer” is, I’m not the most knowledgeable guy around when it comes to MG-V8 mods. I also understand you can cut just so much out of the front crossmember for pan clearance. I notice no one is doing it, but in order to get the front of the motor lower what happens if we relocate (make new) the steering rack brackets to a lower position? .

Paul,
I achieved a little more clearance by grinding about an eighth of an inch off the front lip of the oil pan and by adding quarter inch shims between the crossmember and frame.
The shim idea was suggested to me by a guy who has been racing MBG's for years.

Duh! I never thought of that. See, that's what makes this a great site. Thanks a lot Steve, I'll try that.

"P""

One more question, in doing this, would 1/2" shims be too much? Being able to lower the front of the motor that much could also give a little more clearance at the top of the transmission and restore the stance of the car to origional to compensate for the weight of the V8? Not to mention changing the steering shaft angle for more header clearance.

Paul, I don't think that the standard MGB special tapered xmbr attachment bolts are long enough to add 1/2" spacers. At best you might be able to manage 5/16" - 3/8" ( the caster reduction wedges that are sold are about this thickness),

I checked and I don't have enough threads to use spacers so I'm back to lowering the steering rack or not to lower the steering rack, I guess that is the question. Anyway, I'm not doing it untill it has been talked to death and I'm sure I'm not shooting myself in the foot which is what I'm thinking right now.


"P"

Use the RB bolts and spacer or RB crossmember.

Paul,

If you fit the rubber bumper X member you will need a custom pinion shaft with a UJ at the rack end to make it all line up and then of couse to get the ride height down to chrome bumper height you end up compromising the suspension geometry!

IMO better to retain the chrome X member and find another way to achieve the required clearance, moving the rack down in relation to the suspension does I believe create bump steer problems and you will still have to modify the pinion shaft to get it to line up.

Brown and Gammons in the UK do a castor correction kit For £31.00 which properly locates the X member ( other kits don't)and lowers the front of the X member for a castor reduction of approx 3 deg. to a figure that is more compatable with modern tyres.

It does reduce steering effort and very noticeably reduces scrub at full lock when manoevering.

Kevin.



Edited 1 time(s). Last edit at 03/16/2010 08:51PM by castlesid.

But Kevin.....spacing down the CB cross member is the same thing. :)

Not sure I understand the issue with CB vs RB steering rack pinion shaft length. I have both a mid '70's CB (2.92 turns lock to lock) & RB (3.57 turns) rack assemblies, and the pinion shafts are the same length (I've had them both installed in my "76 conversion. These, of course, are left hand drive assemblies and may be different from those offered in the home country.
I think using a RB xmbr is probably Paul's best bet given his circumstances - the bump steer issue, imho, is somewhat overblown for a daily driver.

Carl,

The difference in height for the chrome and rubber X members is 1 1/2" so presumably the bolts/studs have the same difference in length.

The bolts/studs have shoulders to locate into the underside of the frame rails which is important otherwise the X member is not properly located and you will overcompress the mounting rubbers.

The Brown & Gammons kit has a spacer and slimmer nut which go onto the bottom of the stud to compensate allowing the to to properly locate and the kit has shims for the rack mountings to provide correct alignment of the rack. The frontline wedge kit does not have this.

For information on bump steer Dave Headleys site Fab Tech has an excellent article on the subject.

Pictue of B&G's castor reduction kit


Kevin.