Special Thanks to Scottie-GNZ for his master brain storming ideas. Decided today was the last day the Mazda would roll around using 4.11 gears. Don't like the gas mileage, don't like 3000rpms cruising on the highway and certainly don't like racing at the track in 4th gear. They are just too short for what I have planned for this car.

With no other options for taller gears, we went on an adventure today that will surely set this converted RX-7 apart from the next! Hope someone finds use of this info. I'll add to this thread over time.

July 20 2003
Mazda diff vs. Corvette diff

Corvette diff cover was shortened. The cover was so wide that it interfered with the shocks. No choice but to shorten it.

Mazda diff 'ear' will be grafted onto Corvette diff cover. Looks funky but after it's welded and reinforced it should work great.

This is a picture of the stock Mazda diff flange. I will have these resplined or new ones created to install in the Corvette diff. Stock Mazda length CV's will be installed.

That's all I have for now. Still need to lengthen the driveshaft and make a simple front diff mount. The good news is the diff does fit (eventhough it's much larger) and so far there are no show stoppers. 2.59's here we come!

__________________
1993 Mazda RX-7 w/ Buick Grand National Drivetrain, Viper 3.08 Rear
11.3 @ 128MPH

1987 Mazda RX-7 w/ Buick Grand National Drivetrain
10.79 @ 126.74MPH SOLD

For Details See:
www.MisRed.com

Click Here to see Buick Grand National Powered cars!

Love to read that info... is your website up? I can't seem to get to it....

Ironically my colocation provider is having an outage today. I am sitting here on my hands as 250 websites that I host are dead in the water.......

__________________
1993 Mazda RX-7 w/ Buick Grand National Drivetrain, Viper 3.08 Rear
11.3 @ 128MPH

1987 Mazda RX-7 w/ Buick Grand National Drivetrain
10.79 @ 126.74MPH SOLD

For Details See:
www.MisRed.com

Click Here to see Buick Grand National Powered cars!

Man, I know that feeling. Hope they get it back up soon....

I wondering why you and scotty decided to run the vette pumkin?Other than the fact that he is familiar with them..

Im pordering running a late model T bird rear pumpkin or in my case a mark8 unit..8.8 rear gears are cheaper for me..I found an axle remanufacture that will mate the two CV axles together as soon as get off my behind and ship them out..Probally going to make custom shafts i guess with matching spline counts..


I'm not sure but dont all vettes come with U joints..Im taking that you are going to have your mazda shafts to bolt into the stub axles on the vette pumkin?

I am running the C4 IRS because I was looking for a 3.0x:1 ratio and wanted to swap out the entire Z-car IRS. An entire C4 IRS came my way cheap. I am not running just the pumpkin but the entire IRS narrowed 3". In the process I gained 11.5" rear brakes, toe, camber and bumpsteer adjustments. I also got rid of the monoleaf spring and OEM shock and did my own coilover setup to get ride height and shock valving adjustment. Oh, yeah, with the C4 IRS being all aluminum, I shaved 80lbs to make for other things that added weight. Not your typical drag racing suspension is it?

Misred also got his diff at a bargain. We are brainstorming on what to do with the halfshafts but be assured it is only a matter of time.

__________________
Scottie


2JZ Power - 9.51 @ 146.16
Don' be afraid, it's Only A 6

I have also heard the Tbird rear end won't hold up to as much power as the C4 (Dana 36 or 44) and you would have to swap out gears if the number desired was less than 3:55. Not all 8.8"ers were created equal but I guess we won't know until someone tries.

Mike and Scottie- That conversion is coming along nicely. I am interested in how you guys finish the rest. I'm actually interested in what it will cost in parts and how it holds up.

Not sure if I want to go solid 8.8" axle out back or the Vette pumpkin route in my next release of GNX7.

Good ol' white GNX7 is 90% apart and getting ready for the scrapper. INstalling my suspension/wheels/tires into a silver '87 RX-7 (my dad's old one) and driving it until the 13B dies. Hopefully soon!

-GNX7

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NEW PROJECT: '93 FD dry sump LS7/T56 575rwhp goal, 10's@140mph n/a, 9's on nitrous@150mph+, built to road race (Penske coilovers, RacingBrake BBK, Cobra diff....)
'93 FD/LS1/T56 18x10.5 CCW's-439rwhp/385rwtq thru cats! 2800lbs with full fuel 1.13g's in SCC Mag "USCC", 11.42@127.4mph n/a SOLD http://209.177.55.37/scc.htm
'87 RX-7/Buick GN power- stock GN turbo 11.62@114mph R.I.P. http://www.wrongmotor.com/gallery/mark_c/
'97 LX450 LandCruiser, BBGT35R turbo kit , elockers, 33's, J lift, armour'd

Mark im not sure of where you get your 8.8 info..ve seen two MKII T bird running in the low tens with a stock 8.8 pumkin..The internals are exactly the same as the sn95 cars and fox bodys..They have 3.27s or so as is so that would work better in a steer car...From what i see it mechanics that are scared to pull them apart but who knows..

Ir rather go with a vette setup but for my useage i would end up running just the pumkin anyways.Cant wait to see the finished product..

Scotty just remember that what ever goes wrong at the sept meet this year that i give you special permission to drag me out from under my car by my legs to check out your car..

Custom Stub Axles made today. In efforts to keep everything in one thread, Click Here.

__________________
1993 Mazda RX-7 w/ Buick Grand National Drivetrain, Viper 3.08 Rear
11.3 @ 128MPH

1987 Mazda RX-7 w/ Buick Grand National Drivetrain
10.79 @ 126.74MPH SOLD

For Details See:
www.MisRed.com

Click Here to see Buick Grand National Powered cars!

Man you guys aren't wasting any time.:yeah:
Excellent thread.
Thanks
Jim

__________________
(AKA FJM57)
The time you enjoy wasting is not wasted time.
-Bertrand Russell-
88 GXL 94 5.0
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