black_c7

hey guys i started my build last feb and has just almost finished it

1-a&a kit with YSI unit
2-pulleys uper 2.85 lower 8.25
3-pistons lowered compression to 10.5.1
4- compstar rods
5-32% cam package
6-alky duel nozzles 15 gph 10gph
7-ZO6 hpfp
8-FSP breather
9-ARH LT 1 7/8 with non catted x pipe

it made 680 whp at 6500 rpm,

IAT was 185,


AFR between 10 and 11 with


15 PSI


11*timing !!!!!


what do you guys think is wrong with the build ?
what is the best AFR ?
would i be able to raise the rpm to 7k ?

guys choose a good tuner ! my build would have gone double the stock power, but my tuner was bad and he made just 680 with those tons of mods and money spent in the car !

joemosfet

Hmm, first check for the obvious: any leaks anywhere on the boost side, pulley slip, check your spark gap (.28 to .45). After that, you'll need to start doing some heavy logging, fuel pressure, lambda, and spark come to mind.

Target AFR at wot is 12.2 I believe.

7krpm? Depends on your cam and valve springs, I suppose. Hopefully somebody with more knowledge can chime in here.

black_c7

no leaks no belt slip, not sure what was the gap,

wouldn't be able to answer what is the fuel pressure, lambda and spark since the tuner looked the computer.

AFR is at wot, to the end of the 4th gear it become 10.8ish

for the 7k RPM my car has has duel 660 BTR springs

joemosfet

Running this rich will leave a lot of power on the table. I'd say get this looked at.

black_c7

that what I'm thinking of but it not gonna get that much power

schpenxel

How much boost?

Is this tuner experienced with C7 builds at this level?

black_c7

15 psi, the tuner is good and most of the S/C C7's go to him in my country

robert miller

Gap should be around 28 are lower you just need to play with them until you hit that sweet spot on the gap.

The 10.8 is low for WOT but then again that running a little lean should give you better hp. But you also take a chance of blowing up the motor also.

You cant beat Brain Tooley stuff unless you are going big time racing on parts. Brain know his stuff on a cam and heads set up on these motors.

black_c7

so do i need to get it a little richer or let it get lean for best performance ?

that what i read about Brain Tooley springs, would they let me get into the 7k rpm safe ?

robert miller

The 2.85 pulley will be overspinning the YSI but it loves that.
With this pulley you should be around 22 to 25 lbs of boost at this point at WOT. But then again full set up on this motor will have a lot to do with that.

The car should be at that with it any way with 10.5.1 on the comp.

In my c5 with a RHS 427 motor with a ysi then a f1x with a set of trick flow 245 heads that Brain had did a ton of work on I was pushing 23 psi of boost with a YSI set up. But with a small set of heads you should be even higher in boost than that with a 2.85 pulley

Something for sure is wrong with the set up are the tune if you don't have a bad leak someplace in your set up are a ton of slip in the belt.

robert miller

really don't need to be that lean at WOT. I am like the other guy something has to be wrong on the tune are the set up. You should be close to 950 plus RWHP with this 2.85 pulley with a YSI.

The YSI loves to be over spun puts out its best then.

robert miller

How much timing in the set up at WOT. Again with those IAT at that shouldn't be pulling timing out of the motor. But for sure the YSI with a 2.85 pulley and 10.5.1 comp at 6,k plus rpm should be putting down more than 15 psi of boost.

But then again 760 rwhp on a really safe tune will take down out here on the street 95% of the cars out on the street.

Plus ever more than rwhp is the driver and how much seat time he has with the set up are car.

schpenxel

I'm more worried about whether that AFR is real--wonder what the injector PW is at.

black_c7

The 2.85 pulley will be overspinning the YSI but it loves that.
With this pulley you should be around 22 to 25 lbs of boost at this point at WOT. But then again full set up on this motor will have a lot to do with that.

The car should be at that with it any way with 10.5.1 on the comp.

In my c5 with a RHS 427 motor with a ysi then a f1x with a set of trick flow 245 heads that Brain had did a ton of work on I was pushing 23 psi of boost with a YSI set up. But with a small set of heads you should be even higher in boost than that with a 2.85 pulley

Something for sure is wrong with the set up are the tune if you don't have a bad leak someplace in your set up are a ton of slip in the belt.
robert miller is online now Report Post

really don't need to be that lean at WOT. I am like the other guy something has to be wrong on the tune are the set up. You should be close to 950 plus RWHP with this 2.85 pulley with a YSI.

The YSI loves to be over spun puts out its best then.

How much timing in the set up at WOT. Again with those IAT at that shouldn't be pulling timing out of the motor. But for sure the YSI with a 2.85 pulley and 10.5.1 comp at 6,k plus rpm should be putting down more than 15 psi of boost.


engine is stock 376 cubic, heads also stock just duel springs, from what i saw with this similar pulley setup they get between 17 to 20 psi and would easily make 800+whp, and I'm not sure what is the timing, I'm 100% there was no leak, maybe belt slip since the belt was replaced two times in 2 months, all i know is 15 psi is nothing for a ysi head unit so there most be something wrong happening, but not yet to find out

black_c7

wouldn't be able answer what is the injector pw since the computer is locked, AFR is as what i said was between 11 and 11.5 until the end of 4th gear it becomes 10.8ish

Earl H

185 IAT? Any timing being pulled at that level?

Cordes Performance Racing

your tuner locked the pcm? If so 99% of the time locked pcm's are on cars that perform like garbage, blow up, and do a bunch of stupid stuff. Those tuner's that lock their stuff it seems do it to keep people from seeing the garbage they put in there.

I know your on meth but is the gas in the tank 91,93, race gas, or e85?

black_c7

as i said i can't answer since the computer is locked

black_c7

that what i think about the tune, i told him to unlock the pcm, then he told me if i unlock and anything happen to the car don't come back to me, since he did the assemble and the tune, i couldn't tell him to unlock the pcm to be on the safe side if anything goes wrong

schpenxel

If his logic for locking it is so you can't change anything, then he should at least give you a copy of what is on there IMO.. even if it's left locked (which I agree with Joe's point on...)

And pretty sure you can log it regardless of it being locked