MR2 Owners Club Forum banner

81 - 100 of 536 Posts

·
Registered
Joined
·
211 Posts
I was just at "widebodystarlet"s place last weekend and the build looks amazing in person... the amount of work is insane !!

All the extensive mods to the back end are allowing this V8 to fit in nicely with room to work around it.

This MR2 is going to be scary fast on the street putting down that V8 power on the road !!
 

·
Registered
Joined
·
677 Posts
Discussion Starter #84
One exam left, which mean's I've got plenty of time to procrastinate and work on my MR2!! :) Today I put the transmission on the engine, also marked the new x-member where I'm going to need to cut it to clear the transmission. Axle alignment looks pretty good but I won't know until I've got the suspension on. Which means I need to make the crossmembers work. Just waiting now to see if I can borrow a plasma cutter again :) Pictures!






 

·
Registered
Joined
·
677 Posts
Discussion Starter #86
I'll take some pictures today of the gap between the engine and firewall, maybe I'll put the fuel filler neck in there for fun :p I didn't want to stretch the chassis too much as I wanted the wheel wells to fit inside the taillights and I also wanted to stay around the 104.5" wheelbase that seems to be so widespread among mid-rear supercars.
 

·
Registered
Joined
·
2,507 Posts
Its more about the ratio between wheelbase and track.

The McLaren F1 has a 107" wheelbase, but is much wider than the MR2.

My first car was a 84 Ford Thunderbird (non turbocoupe) and it had a 104" wheelbase, but I don't think anyone would consider it a supercar.
 

·
Registered
Joined
·
2,507 Posts
on page 27 of this book , it has a comparison table of wheelbase to track of a bunch of different race cars.

At the top (with the most "square" ratio) is the 100cc shifter Kart. 1.155
in the middle of the table is the Lotus 7: 1.600
at the bottom is the Peugot 205 Turbo 'Raid" 1.922

They do say the following in the book: "Wide wheels, together with major inset or outset alterations have a big effect on the ratio. Peugot's large increase was to accomodate long range tanks rather than for roadholding.
Generally, a small figure should reflect a low polar moment
[of inertia] and vice versa but, even then, distribution of weight within or outside the wheelbase may make a bigger difference than the actual ratio."

I added the part in square brackets. Polar moment of inertia determines how quickly a car can change directions, for example: in the slalom. A Lower moment is better, and hence why I love mid-engine sports cars like the MR2 over conventional front engine cars or front engine, rear transaxle (dumbbell cars like the 97+ corvette or Porsche 928--they have a polar moment of inertia 'profile' resembling a dumbbell for weightlifting)

Anyway, if you can create a car with a ratio closer to square and at the same time concentrate the mass to the center, you will get a better handling car.
 

·
Registered
Joined
·
677 Posts
Discussion Starter #89
The engine weight sits forward slightly of where the old engine hung, but now the rear wheels are further back, which means I've moved the weight closer to the center by relocating the rear wheels correct? I've been wondering about ideal track width based on the 104.5" wheelbase I now have, but I couldn't figure out how the tire width comes in to this calculation. But basically as I see it, you're saying since the wheelbase is longer the track width needs to increase just to retain the handling aspect? I see how that makes sense. My new tires are wider and I'm going to need spacers just for them to clear the suspension.
 

·
Registered
Joined
·
677 Posts
Discussion Starter #90
Had a few hours to kill this morning so I trimmed the new crossmember down to size. I test fit it as well. It looks like I can't make the mr2 crossmember and the audi one connect as one piece... too much work and no benefit I can think of. For now I just clearanced the audi piece so the control arm bolts can could go into the mr2 piece. Also jammed one of my new rear wheels in the back wheel well for fun. They will have much wider tires on them when they finally go on the car. Pictures again!

Some shots of the clearance between engine and firewall now that the engine is on the right angle:




This is where the fuel filler neck goes, lots of space:
 

·
Registered
Joined
·
2,507 Posts
Where did he say the motor was bad?

I must have missed it. I only saw that from his donor Audi car, the quattro trans was bad. That doesn't matter as he is using an Audi 2wd trans.

Also, if any part of the bottom end of an Audi v8 is bad, the whole bottom end must be replaced as a short block. Audi will not sell rings, or crank bearings, among other things. They only sell head parts.
 
81 - 100 of 536 Posts
Top