Quote:
Originally Posted by Fingie
the RX-7 was designed with almost 50/50 weight ratio.... The duramax could quite surely turn it into a pretty crappy handling one, too front heavy.
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Yes the FD Rx7 actually had pretty close to 25/25/25/25 weight distribution..
However..you will be surprised to know the 13B-REW (Twin turbo 13B Rotary) is actually an extremely HEAVY setup...
Replacing the 13B-rew with a LS3 actually results in a LIGHTER car...a few KGs only..but lighter nonetheless..and the v8 keeps the weight distribution in almost exactly the same spot as the 13B..
Now I am not stupid enough to believe a duramax is the same weight as an LS3, so obviously the big lump will change it a bit.., so lets do the maths (Roughly!)
LS3 = 211KG / 466lbs
LBZ =379KG / 837lbs
FD RX7 stock weight ~ 1298KG / 2862lbs
Assuming a 50/50 weight balance, and noting the engine is BEHIND the front axle (13B and the v8 both fit behind..infact the v8 has LESS weight infront due to not having some many ancilleries infront of it!)
we will work on 650KG / 2430lbs approx front axle weight based on 50/50 distribution..
As the engine sits behind the axle..lets work on 2/3rds the weight of the engine differential..
Approx 170KG heavier between the engines (13BREW/LS3 --> LBZ)
So if we allowed 2/3rds the weight, it would be 110kg extra on the front, and 60kg extra on the rear..
We also need to allow for the gearbox, which the allison is heavy at around 300lbs..(136KG), which would be DOUBLE the weight of the FD 5 speed box..so we need to add about 60KG in the centre of the car (tranny would put close to 50% of its weight to either axle)
Adding this to the 650KG per axle
Front 790KG
Rear 740KG
Curb Weight 1530KG
Giving 51.6/48.4 weight distribution....not many cars get to that
I hope the LBZ weight figure I got from Wiki is correct...