ChevyNo1

Well, I still have a smoking turbo problem, but figured I would finish dyno tuning it anyway. I'm pretty sure I've maxed out these little turbos, unless someone else can some up with an explanation.

The extra cubes of this motor over stock displacement is eating the capacity of these turbos I think. Saw it spike to 15psi on race gas, but settled within a couple of seconds to 12. That and really didn't see a lot of increase in hp beyond 12.

Here's the dyno sheet:



#26 is after the first couple of attempts to straighten out the AF. This was at 11psi. #29 is final #'s on pump gas ( still 11psi ), I'm not thrilled about the peak #'s but we all know that's a small part of the equation. Nic doesn't really feel safe about running more than that on the street on shitty 91. I think we could push it further . . .

At 2500rpm I'm 60ft/lbs of torque more than the last nite of my stock motor. I hold on to it longer at the end also, so all in all I'm quite happy. #33 is the #'s on on a 50/50 mix ( doh, too much 91 in the tank, oh well ) of 91 and 101. That's the reason we didn't go crazy with too much timing, probably only had around 96 octane. At least I cracked 700 in torque!

Now . . . believe it or not, I'm still running the stock LS1 intake . . . and the TEA heads are unported . . . they were just cleaned up with larger exhaust valves put in ( I was on a budget ). How much could the heads/intake be holding me back? I'm also running a 222/218 563/561 114lsa cam . . . could it be hurting me any?

- Dug

onfire

iTrader: (17)

I think that's a great curve! Plenty of power for low tens. Depending on your weight 9's.

How are you controlling the boost?

Did you try to over boost it to 17psi for a pull?

Exhaust set-up?

Good job!

cablebandit

iTrader: (37)

ls6 intake would help for sure!!!!!!
I understand the turbos being maxed but shouldnt they get any ls1 to 750ish before they are maxed?

ChevyNo1

onfire, thanks! I've got the Greddy Profec-B controlling it. Did not try to overboost it, didn't have a great mix of gas, I'd estimate 96. Exhaust is 3" all the way to the rear, no cats, bullet mufflers dumping in front of the rear axle.

That's what I'm wondering cablebandit. I have the 35's, didn't you have the 37's? And how much did you get on those? How much do you think I might realistically gain from the ls6 intake alone? BTW, on 91 octane, what kind of timing curve would you guys run with how much boost on my setup? I think the timing could be higher than it is on pump gas even, I think I'm sitting as low as like 16 and as high as 20 . . .

- Dug

cablebandit

iTrader: (37)

i have the smallest incons...whatever they are. My last dyno was sae 736/750ish at 15.5psi on my autometer boost gauge. On my eboost2, that same boost shows as 16.6psi
My dynos are always on 93/meth and timing is around 15 degrees ramping to 18. my other cam dynod 703/775 at around 15psi

onfire

iTrader: (17)

643rwhp at 12psi sounds dead on for an efficient set-up. Add 3 psi and you'll be with Jerry.

Are you running the 0.86AR turbines? A few were 0.64.

ChevyNo1

cablebandit, did you hold boost all the way? What was your CR? onfire, I'm not sure . . . how would I find out, would it be stamped on the housing?

- Dug

onfire

iTrader: (17)

Yep, stamped on the iron housing.

cablebandit

iTrader: (37)

mine always holds boost...it will hold 20psi
my compression ratio is 9:1 and then i have #317 heads so it should be around 8.75:1
I dunno which housings i have

ChevyNo1

Interesting . . . why do you think my boost is dropping off then while yours holds boost? I'm also around 8.7:1. Something's not right . . .

- Dug

ChevyNo1

And nobody knows how much I might gain from going from the ls1 to ls6 intake?

- Dug

ChevyNo1

Oh yea . . . another thing . . . what about the heads? They are unported . . . just larger exhaust valves, stock casting #317

cablebandit

iTrader: (37)

mine are some old GTp ported heads......stock valves
The ls1/ls6 intake swap netted me a noticeable butt dyno increase. I dunno how much but once you get over 500hp...an increase that you can FEEL has to be a good amount. ESR noticed the same increase up top when he switched.
8:75-1 346
gtp #317 heads
ls6 intake
215/215....550ish cam 114lsa
double valve springs
stock maf
tr6 35 gap
ported tb
stock intercoolers
I wonder if the ls1 intake could be holding you up that much. harlan switched i think while running the Incons so maybe he will chime in.
remember harlan made 600 mustang dyno on a stock motor at 10psi with racegas....so i dont think the heads are your problem

ChevyNo1

yea, what octane was he running? I heard he ramped the timing all the way up to 30 on that gas . . . and my cam should be fine then, it's a 222/218 561/563 114lsa . . .

cablebandit

iTrader: (37)

i dunno what harlan ran for timing.....thats kinda why i posted the race gas thread. Mine is about maxed out so i guess i could try some c16 and see what it does

onfire

iTrader: (17)

Your boost isn't holding due to the boost controller settings (my guess). Play around with the controller and get a settled boost around 16-17psi and th hp will come (with a proper tune)...a small spike is normal...my eboost2 jumps to 13.5 then settles down quickly to 12. You probably want the wastegate springs around 10psi.

ChevyNo1

Well, looked over my video . . . I hit 15psi by 4000rpm . . . and then it seems to drop down to about 12 . . . would you consider that a spike?

peter@aps

iTrader: (2)

Dug, What type of exhaust are you running? You may have very high exhaust back pressure which can also limit the potential boost pressure.

onfire

iTrader: (17)

onfire, thanks! I've got the Greddy Profec-B controlling it. Did not try to overboost it, didn't have a great mix of gas, I'd estimate 96. Exhaust is 3" all the way to the rear, no cats, bullet mufflers dumping in front of the rear axle.

ChevyNo1

ok . . . did some examination of my video ( took video of the gauges ) frame by frame.

One thing I've noticed about the last two race gas runs is that they both spike to 15, settle down to 12 . . . now the interesting part. My pump gas dyno was for 11psi. In that run it hits peak boost at EXACTLY 3500rpm. Guess what rpm it hits 12psi in both race gas runs?

3500 RPM

To me, that's telling me that the 15psi is indeed a spike ( explaining why it doesn't hit that until 4000rpm ), and which is why it settles back down to 12psi.

One other possible explanation is my boost controller. A couple of years ago I was having bad boost spike issues . . . so I turned the balance **** on the profec-b all the way to sharp, which is what the manual tells you to do. That always helped but didn't alleviate. Then I checked out the dip switches in the back and it was configured incorrectly. Fixed that and voila my spike issues were pretty well gone. BUT I never revisited the balance ****. Now I either have a boost spike ( which shouldn't be possible according to the controller settings on sharp ) OR I have boost falling off, in which case you need to turn the balance know towards mild. So it could either be a boost spike or it's boost falling off.

What do you think? At any rate all I have to do is do a bit of testing to figure out what it is, just gotta get the race gas tune in and do it.

- Dug