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Finally go the S480 installed, what a pain! I ended up making the 1.32 T6 housing fit. Anyway I got a few street pulls. Back pressure is still 1.8:1, even saw 2:1 at one point. So I'm thinking the hotside is the limiting factor at this point. Not sure what else it could be. Car feels sketchy fast on the street. Have it very slowly ramping in 20lbs VS wheel speed. IAT's are quite a bit lower. They peaked at 111. Around 86* ambient.
I'm sure it picked up a little, but I doubt it fixes my issue. Next track event is halloween weekend. I'll give it another go then.
The white "fuel pressure" parameter is the back pressure. I just never changed it.
Last edited by Forcefed86; 10-16-2016 at 05:59 PM.
I noticed that. Was setup for 11.0 last track outing. Figured if anything it would need more fuel, not less. I believe it's the garbage varying "E85". I put 5 gallons in just before that pull. Guessing I got E70, I'll test what's in my tank today.
Thought I'd update this a bit for anyone running into similar issues.
Guy made me a deal I couldn't pass up on my 370 so the original motor in this thread is gone. I installed an SBE 4.8 and ran into similar issues.
Also talked to a fella with a 388" LS setup running a 2" divided hot-side and trapping 160+ at 3400lbs. So doubting its my hot-side diameter.
Same S480 1.32 T6, BTR .660 dual springs(150ish on the seat), similar small cam 212/217 .565 lift (added 1.8 roller rockers, made no difference) 6800 was about it. (ls6 intake)
Moved my back pressure signal to the turbo housing. Sitting at 1.4:1 @ 20lbs on the T6 S480.
Looser converter, went to a 17 stator from a 14 (still not lose enough IMO)
3.64 gear and 28 " tire now. (still not enough gear)
I swapped out the small cam for a summit stg2. 226/230 @ 113 .600/.575. Suddenly it pulls to 7100ish before tapering off... nose dives about 7300. Still weak rpm for a 4.8. I'd like to get it to 7800ish.
But managed an 8.80 @ 158 last weekend. Though the traps around 7200. 23 psi most of the run creeps to 24.
Cam states its "special lobes" are stable with as little as 150lbs of seat pressure at 7k. With a "soft" opening exhaust valve event. Seems to hold true anyway. BTR Dual .660 lift springs on it now. will be shimming these and shooting for more RPM. Guessing the LS6 intake an 78mm TB are my bottle necks.
I was thinking the same thing the ls6 intake and stock tb maybe try a cheap sheet metal one with a 92mm tb and see what difference it makes
Defiantly on the radar. May try shims first to get it closer to "correct". I'm slightly worried about the 30-40hp I'll lose down low. Afraid I won't be able to get up on the trans brake boost target with the wimpy 4.8. May need looser stall and intake to get it done...then more gear likely. Hoping to avoid that rabbit hole for now and try little "easy" things. May be a winter project.
Defiantly on the radar. May try shims first to get it closer to "correct". I'm slightly worried about the 30-40hp I'll lose down low. Afraid I won't be able to get up on the trans brake boost target with the wimpy 4.8. May need looser stall and intake to get it done...then more gear likely. Hoping to avoid that rabbit hole for now and try little "easy" things. May be a winter project.
What rpm are you leaving at? maybe a tbss manifold and a 92mm tb then if your worried it won’t get to the 2-step with a sheet metal intake
3 blade step up on converter, more gear, and 2" shorter tire helped a bit too I bet. But Yea I'm leaning towards the cam as well. Which is odd as other have revved the 220 trick cam farther than 6800ish. And I verified the spring pressures of 150 closed and almost 400 open.
Originally Posted by ls3fox
What rpm are you leaving at? maybe a tbss manifold and a 92mm tb then if your worried it won’t get to the 2-step with a sheet metal intake
4100 and around 8lbs. 4000 bogged and 4200 spun. PBR 28".
I'd love to run that manifold but it won't fit under the factory hood! I run it on my mustang setup and like it alot!
Last edited by Forcefed86; 06-16-2020 at 01:41 PM.
Just a suggestion since its an easy swap. How about pulling the hood and adding the intake just to try would be cheaper than buying an aftermarket + throttle body only to find out it didn't do anything. Ever do a pull on a non mustang dyno see if it pulls past 7200 since its not quite so loaded. Just thinking out loud.
Just a suggestion since its an easy swap. How about pulling the hood and adding the intake just to try would be cheaper than buying an aftermarket + throttle body only to find out it didn't do anything. Ever do a pull on a non mustang dyno see if it pulls past 7200 since its not quite so loaded. Just thinking out loud.
Def thought about it. Even had a buddy offer me his hi-ram. Problem is I know I'd like it! Then what do I do!? I'll change a few other things before toying with intakes. As long as it gets up on teh converter I don't care avout the power losses down low the short runner cheap intakes.
My thought was if boost is just extra air density, can't see the TB size being a huge restriction. May stop me from revving to 8k. But shouldn't stop the power increases per pound of boost at the RPM I'm already at. I wouldn't think anyway. Haven't had it on a dyno. But the converter/gear/tire change did help quite a bit I believe. Still dropping big on the shift. I had my order in for a 19 stator converter but the guys at PTC talked me out of it and into a 17. Wish they wouldn't have!
Def thought about it. Even had a buddy offer me his hi-ram. Problem is I know I'd like it! Then what do I do!? I'll change a few other things before toying with intakes. As long as it gets up on teh converter I don't care avout the power losses down low the short runner cheap intakes.
My thought was if boost is just extra air density, can't see the TB size being a huge restriction. May stop me from revving to 8k. But shouldn't stop the power increases per pound of boost at the RPM I'm already at. I wouldn't think anyway. Haven't had it on a dyno. But the converter/gear/tire change did help quite a bit I believe. Still dropping big on the shift. I had my order in for a 19 stator converter but the guys at PTC talked me out of it and into a 17. Wish they wouldn't have!
My little edelbrock 80mm throttle body had no problem zinging to 78-7900 on their pro-flo xt intake. That one performs very similar to a hi ram but is a little shorter so it clears some hoods, it cleared my stock hood.
10-16-2016, 05:13 PM
I'll change a few other things before toying with intakes. As long as it gets up on teh converter I don't care avout the power losses down low the short runner cheap intakes. 