Twin Turbo 4.8 Results / Single 80mm Build
 

Finally got some results I'm finally happy with. This set up has been fighting me all year.

Chassis: 1984 SVO Mustang, full factory interior, 8pt cage, never been weighed but I figure its 32-3300lbs with me in it. 255 ET Street R tire

Motor: 2009 4.8, 241 heads (about 8.8:1 CR), BTR Stage 2 TT cam, LS1 Intake, stock head gaskets, reused head bolts

Turbos: Home made hot side, Rev9 7268's, Treadstone intercooler

Runs on an MS3Pro Ultimate, 210lb injectors and E85

On 13psi its only been low 10s at 133mph. It takes a good amount of boost to get this thing to move but last night it went 9.32 @ 147.5 on 24psi/14.5*. Need to get the 60' figured out, hoping to see 8.99 next time out.

https://www.youtube.com/watch?v=ba56...ature=youtu.be

https://preview.ibb.co/c4SmKQ/IMG_1223.jpg
https://preview.ibb.co/cAvTYk/IMG_0548.jpg
https://preview.ibb.co/cCENtk/IMG_2905.jpg
upload my photos

Hell yeah! Looks good. What trans and using tb?

It's a TH400 with trans brake. Using the "bump box" feature on the MS3Pro.

Pretty cool, bad azz ride for sure

Thanks guys.

Keep at it ... If you do it the numbers will come ..
Nice car ..

Cool set up. I dont know everything, so just asking, but is that compression ratio rather low? Any particular reason why? Still some stout numbers, im just curious is all

Long story short, the motor ended up being a spare parts type build. Its got 241 heads off an LS1 I got for $80. The combustion chambers are a bit bigger than any head a 4.8 came with.

Very nice setup. Super clean under the hood!

Got ya. Makes sense now. And it seems to be workn just fine!

And who said lower compressions couldnt work....

And you could easily run a lot more boost very safely too.

Nice results. Love those little motors that can:judge::judge:

As everyone says, I definitely think there is more in it. Before that last pass I added 1.5* timing and it picked up 3mph. I've had it on 25-26psi before with a lot lowering timing. Going to wait until we get some cooler air and turn it up a bit more.

did you use to race this car at Mid Michigan with the 4 banger?

Is that Stanton?

Yes. Use to be a guy that had one that raced in the street car program

No that's not me. I did the 2.3 turbo thing for a while though, until I got tired of making 400hp.

Congrats! It can’t be in its happy spot timing wise if it’s still picking up that much per degree. How do the straps on the plugs look heat wise?

We need to tap the hotside and see what back pressure is doing with these turbos. Maybe they are working a lot harder than we think. MPH and trap speeds are on par with the small wheel cast S475 setups. (if not a little less). Yet looking at Chris Bishir’s old S366 results… his SBE 5.3 was picking up almost 24+ hp per pound without an intercooler on cast S366’s.

Saw VSracing dropped their S366 clones down $350. That turbine wheel looks funky, but might be worth a shot. I’ll donate $100 if you try them out for us! ;)

I have not looked at the plugs. There is a bung in my hotside near the turbine inlet for back pressure, but I've never hooked anything up. I can't imagine the S366's would be any worse than the 72s for spool, and they have been proven to work very well. It would take a little work to make them fit. After seeing a guy on YB make 960whp with a pair of On3 61/65s, those sounds pretty enticing for the price point and would drop right into my car.

Sounds like a great option, I hadn’t seen anyone using those before. Does the guy have a link to his build? Curious about the rest of the engine run down. Any track times with it? What kind of boost?