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MG MGB GT V8 Factory Originals Technical - Engine angle

I have finally fitted my 4.2 Rover plus Chevy T-5 into my 1974 Chrome bumper roadster.
What should the angle of the engine (measured at the rocker covers) be relative to the car? Should it be horizontal, tipped up at the front, by how much and relative to what? The front of edge of the engine oil pan is about 3/8" above the steering rack.
Also, the distance from the top of the transmission tunnel (at the gear stick hole) down to the top of the gearstick mounts on the T-5 is 3", is this OK or should the back of the transmission be higher? I am using D&D engine and transmission mounts.
Regards
Tony Bates
Tony Bates

Tony,
Ideally, the engine angle and RA pinion angle should be the same (ie parallel) and, with at least a 1 degree operating angle at the U-joints. You will probably find that your engine is about 4 degrees, tail down, relative to the body side chrome strip being "zero" and that your propshaft is about 3 degrees, tail down.
I have a RB setup that used D&D's engine mount and I'm not sure it reflects the same angles as a CB car but mine are consistant with the above angles.
For another reference point measure the clearance of the T-5 tailstock housing to the fixed crossmember - that should be 1/4 to 3/8".
Ultimately, the engine location is pretty much fixed by clearances of bonnet to air cleaner, damper pulley to steering rack, and exhaust headers to steering shaft.

Graham
Graham Creswick

That's awfully far down for the gearbox. Surely the stick will not be able to operate freely. Tranny should come right up to the top of the tunnel. Tons of different variations possible here, depending exactly where you've positioned it all fore/aft.
Ted

Tony, place the engine where you want it to be.
Once you have the engine in place, set a angle finder or a buble on top of the manifold (Carb mounting base)the engine should be level from front to rear and from side to side.
Once you locate the engine and is mounted, place the angle finder on the flat spot on the differential yoke, read the degrees, it should not be more than 3 either facing the floor board or the ground. Next place the angle finder on the flat spot of the starter mounting face and it should read no more than 3 defgrees opposite to the differential.
This will put the two lines parallel, one line from the transmission and the other from the diferential.
3 should be the max the ideal is 1 1/2 or 2 degrees.

The angle can be adjusted with shims on the differential. Do not adjust by tilting the engine.

Hope this helps you.

Bill Guzman

All the angles & clearances are dependant on the engine location. On my '74 GT, I have located the engine more to the rear than most. My '66 roadster has a more traditional location. You want to have the top of the intake as level as possible as this affects the float level in the car. This means approximately a 3-4 degree down angle for the engine. Level is ideal, a degree one way or the other is not critical. Whether this is possible depends on the amount of tunnel bashing done prior to the installation of the engine. Too little, your engine will tilt downward too much. This will increase the distance from the tunnel to the shift lever base.

Measuring ftom the transmission tunnel to the shifter mounting base on the transmission, I would expect to see between 2-3". Even a 3" measure should not be a problem. If you find that your shifter is limited by the hole in the tunnel, do not despair, there are several different shifters with different tower heights. Shortest is the passenger car version with the shift lever heated & bent to come straight up. Next highest is the S-10 pickup shifter, then the Van shifter is higher still, as is the aftermarket S-10 shifter by B & M. The higher the tower, the shorter the shifter throw or travel. In order to get the shifter to come up correctly left to right generally required an offset of about 1". This can be accomplished by cutting off the shift lever close to the base & welding back on along side the stub, sometimes requiring a spacer to be welded in between the lever & stub. Front to back location is controlled by engine location & can be adjusted in the same way as the side to side adjustment, but the difference is generally too great to match the factory 4 speed location. Use 2 tunnel covers & cut & weld them together to get the hole in the correct location, or fab a new piece from sheet metal. If using the factory console, cut a new hole in the plastic to match the shifter location & cover the surround area with a bit od cardboard covered in black vinyl & no one will ever notice.

Typical miss-alignment of the drive train to the rear axle is 2-5 degrees, based on past threads on this subject. You may wish to search the archives regards "pinion angle". Up to 5 degrees is acceptable, with 2-3 being ideal to make sure the U-joints rotate in use. 1 degree is marginal, 0 is a problem. You can verify this with Curries or Mosler Engineering, makers & modifiers of aftermarket rear ends, or any good book on chassies engineering. The pinion angle angle can be adjusted quite easily with angled shims available from the manufacturers mentioned, Summit, or Jeggs. The shims install between the spring perch on the rear & the springs. Personally, I have never needed them.
Jim Stuart

Tony,
Beware of local regulations w.r.t. Clearances, particularly in the transmission tunnel. I got rather severely burnt on this .
Initially I set the thing up as per Rogers book with a 15mm off set which centralized the gearlever w.r.t. its tunnel hole. Also I was using a rangerover pulley/balancer so in order to get clearance between this pulley and steering set the gearbox low and the engine high).
This worked great, no mechanical problems at all, ran smoothly with no odd noises.
BUT ;"Not allowed" declared the local powers, must have 1cm clearances, especially around moving parts, ie. drive shaft and pulley/balancer. In short, centralize gearbox, remake mounts and change pulley set up (Arrrg!).
(And I should add @#*%!!!!!!)

So in order to get the gear lever adequate clearance around the "gear lever hole" in the transmission tunnel I had to raise the rear of the gear box 4 cm, which meant lowering the engine about 1 cm to get clearance on the top of the transmission tunnel, which meant discarding the rangerover pulley and using one from an SD1 Rover, which has a longish shaft/gap between balancer and base into which the steering rack will fit with at least 1cm of clearance. Relocation and spacering of alternator and water pump pulleys followed of course.
The motor is now almost level, and still works well.

The take home message is consult the regulations first ( very thoroughly, I though I had), perfect engine angles are the least problem.

Incidentally the police MG GTV8's in England used to tilt/shim the engine over a little to get more clearance between exhaust and steering.
Peter

Jim,
<You want to have the top of the intake as level as possible as this affects the float level in the car>
For reference:
Last night I had a digital angle finder on my (stock 215 Olds) valve cover and intake manifold carb mounting surface. There is a 7 degree difference, which implies that with an engine angle of 4 degrees (tail down) the carb will be 3 degrees (front down) from being level.
Graham
Graham Creswick

This thread was discussed between 09/06/2003 and 13/06/2003

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