Put the quad turbo 4.8 on the dyno.
 

560 wheel spinning the tires. Power climbing HARD.
Running pump gas timing with E85.
4.8 on just 8 PSI through a TH400, shutting it down 600 RPM early.

I'm hoping with a tire change, 4 more degrees of timing, and 600 more RPM, I can make 650 wheel with my little 4.8 on just 8 PSI. Then I can start adding boost back in.

Im on a new trans. Built 400 with a 1 + 2 leave brake and buttonless reverse. Once its dialed in, a 10.90 pass will secure the Dana 36 record, then I'll see how far I can push it.

https://cimg1.ibsrv.net/gimg/ls1tech...280fdca33d.jpg

https://cimg5.ibsrv.net/gimg/ls1tech...cfa7a4c831.jpg

Very nice, that intercooler reminds me of a Rolls Royce grill. Car should run good no doubt, although I do wonder if a glide would be better suited for it (I'm assuming the car is lightweight).

Isn't that thing light? I would think it's got a 9.90 in it, not a 10.90.

I don't have an exact weight. Somewhere in the 2400 lb range.

I do more than drag with the car, so glide was a no-go right now. 650 wheel at 2400 lbs should be way into the 9s. This 7.75" rear isn't going to last forever.

Even with the TH400 I bet you get darn close. Shouldn't even have to launch on kill if the tune is good and it's got a tire.

I've had it over 20 lbs of boost. The fact its picking up over 30 HP per PSI before the turbos even hit efficiency means it should have another 400 horsepower in it to get back to where I had it before. Beyond that is uncharted territory.

The few 24 PSI hits I had before were all accidents even though it stayed alive, so we will see.

That thing is cool. Very nice.

I'll try to get the video posted up later of the pull.
The graph looks pretty bad because they were trying to get some speed on the roller before hitting it to see if we could keep it from spinning.
It starts making boost around 3200 but it builds up pretty slow because I'm keeping timing out of it to keep the 7.75" IRS alive.

Once I get my fuel cell swapped over to a gravity fed one (I have a top feed now), I'll go back to the dyno with slicks and start dialing it in with more boost.

what are you gonna do after the 7.75 dies?

i've been looking at IRS swaps for a project on the sketch board and considering the g35/g37/350&370 Z rears

R190!

8.8 IRS. $100 from the local yard, and parts are fairly cheap for them. I'll keep a mostly-C4 IRS setup and swap the 8.8 into it.
There are definitely stronger IRS setups, but NOT for the price. You can even score the newer "Super 8.8" setups complete for a very reasonable price.

oh cool same-ish track width?

No, I'll probably use an explorer 8.8.
I can get a batwing diff cover plasma cut that'll bolt the 8.8 into the car, and I'll have axles made that let me use the 8.8 inner axle stubs with the C4 corvettes outer axle stubs, retaining the stock C4 rear spindles and suspension.

oh oh oh gotcha yeah thats easier for your set up. duh my bad.

i'm looking for a whole stout AF rear subframe assy for a first gen mustang

Fifth gen camaro drop-out rear subframe go for $800. Not sure about strength though

Very sweet!

How are you going to keep the 8.8 inner stubs retained? They simply pop in and out with a little retaining clip. Those CVs were never designed to be a suspension structural member, like the C4 Corvette suspension.

Andrew

That has been the only hurdle. I can have the inner stubs machined for C4 style snap rings or some heavy duty retainers. Not a huge deal there. Adapting them to the driveshaft style axles will be the only issue but I have something in the works there. Some of the 8.8 inner axle stubs are 2 piece and a pinion yoke can be adapted to them.

I've never seen 2 piece 8.8 inner stubs. What vehicle used those? Also, the Explorer diff uses different inner stubs that the car IRS 8.8s

I'll get pics eventually when I get the 8.8 torn down to swap out the ring gear. Right now I'm more worried about getting the electric power steering into the car.