04 cobra shortblock with 97 b heads stock, d1sc new numbers.

[uberstang1]

Well have an 04 shortblock with 97 heads and just got a calle from my tuner, with a 3.4 blower pulley and a 10%od crank pulley the car is seeing 21psi at 6k rpms and 590rwhp. Spark blowout is the reason it shutdown at 6k. My options are to set the rev limiter and stick with the numers or get a BAS and push her a little more for some more power, but whats everyones opinion on the power and boost level on 93 pump gas

 

[01yellercobra]

What plug gap are you running right now?

That's on par with another combo I know about that has a D1 on an 04 long block.

 

[uberstang1]

stock coils, msd wires and a .28 gap, need a boost a spark

 

[01yellercobra]

I'm guessing no one makes a good coil upgrade for your car?

 

[uberstang1]

Tried running screemin demons and MSD coil packs, cause me nothing but problems on the dyno when I had my old setup, all problems resolved switching back to motorcraft coil packs.

 

[97snakebite]

Tried running screemin demons and MSD coil packs, cause me nothing but problems on the dyno when I had my old setup, all problems resolved switching back to motorcraft coil packs.

cant rememeber his SN but there is the guy with the green sn95cobra puttin down over 700whp with a D1.. hopefully he sees this and gives a lil input... hey what plugs are u running?

 

[coposrv]

Brutalmetal maybe? I think he has an F1A Made 730 RWHP.

 

[uberstang1]

Im runnin ngk tr6

 

[encasedmetal]

OP_ given the extremely low CR on your motor, your power levels are on par for pump gas. You may be losing some power due to the spark issues however, and a BAS is the best way to fix it. Stock coil packs, with tr6 plugs are the way to go unless you have another plug preference and your gapping is ok. Add a BAS, wired in to run full time and you'll kill the blowout issues.

 

[encasedmetal]

Brutalmetal maybe? I think he has an F1A Made 730 RWHP.

do you mean me?

 

[coposrv]

^ yup. Sorry.

 

[uberstang1]

Yea trying to find a forum BAS atm to ship down to the tuner

 

[encasedmetal]

Yea trying to find a forum BAS atm to ship down to the tuner

I found fastlane in cary NC to have the best price by far.

 

[98 Saleen Cobra]

IMO that's way to much boost for pump gas.. The power isn't there, but the timing is probably retarded to keep the engine going.. I have T-trim and making 640 on 16psi and 20* of timing on pump 93.. I'm not to sure if you're over spinning the D1 either.. I would pulley it so then it's less boost and throw timing over it.. That's my .02

 

[encasedmetal]

IMO that's way to much boost for pump gas.. The power isn't there, but the timing is probably retarded to keep the engine going.. I have T-trim and making 640 on 16psi and 20* of timing on pump 93.. I'm not to sure if you're over spinning the D1 either.. I would pulley it so then it's less boost and throw timing over it.. That's my .02

it's a trade off chris-given his compression- which is pretty low with the -18cc pistons + B heads. He's def not over spinning the D1 if the pull was stopped at 6k rpm.

 

[98 Saleen Cobra]

it's a trade off chris-given his compression- which is pretty low with the -18cc pistons + B heads. He's def not over spinning the D1 if the pull was stopped at 6k rpm.

Yea thats true. I dont' know what the CC is of the B-heads are.. I know that I'm at 8:6.1 compression.. Granted my setup is very conservative even in my AFR and my boost itself on 93. But I'm not taking any chances at all.

What is his compression with the stock 04 shortblock?

 

[encasedmetal]

Yea thats true. I dont' know what the CC is of the B-heads are.. I know that I'm at 8:6.1 compression.. Granted my setup is very conservative even in my AFR and my boost itself on 93. But I'm not taking any chances at all.

What is his compression with the stock 04 shortblock?

pretty sure they're 53cc but pulling that out of thin air this morning. He's below 8.5:1 though for sure. Boost is not the limiting factor as far as a motor goes. it's the timing. Shit- you can make 1000hp to the crank on a factory 5.3 LS motor with a turbo and low timing. Seen it, and it lasted for 3 nights at the local drag way. No, that's not dependability but I think most people are starting to realize that compression and boost are not the enemies we used to think them to be. 99.9% of all tuners will start all tunes with no timing in it, then add timing in 2 degree increments until it knocks- then back it off 2-3 degrees and leave it. I don't think I know of anyone that tunes with the boost in mind- it is what it is and dictates how the motor will act in relation to everything else- heat, valve float, timing, etc.

 

[98 Saleen Cobra]

I gotcha. Makes sense. But not having enough timing puts wear and tear on the guides..

 

[encasedmetal]

I gotcha. Makes sense. But not having enough timing puts wear and tear on the guides..

you talking about the chain guides? If so, they have zero to do with each other. chain guides are worn by rpm. Biggest failures I've seen come from modulars running in the 9k+ rpm range, and then they start to wear down, which can be atoned for with brass rivets. Any other part of the motor will experience 90% of it's wear in the first 20 minutes of life except for the rings of course.

 

[98 Saleen Cobra]

I was talking about the valve guides.. I know on my old motor not having enough timing put more wear and tear on my guides, atleast that's what my builder said..