Sean94Z, good luck with your car. If you look at the red dyno on the dyno chart, that is where my car started, WAY rich, and only 518 at the wheels. After the tune I picked up almost 100 RWHP! You should be right around where I am at after a good tune. Good luck!

Silas, good luck to you as well! I know you have put a lot of time in your Z as well, and I have a feeling once you get it running its going to put down a considerable amount more than me! Keep me posted!

 

i guess we can kinda answer the question about how much of a difference can a good head make on a boosted car..
Here is my dyno..pretty close setup to Call911.....mine has a fully hogged out AFR 227 heads and a smaller cam....with a 3.70 and 7.65 pullies i am seeing right at 15 psi (i would think i would see a lot less boost since my heads are huge and flow a lot better?????????) either way car put down well let’s just say 700rwhp as it was soooo close..all on pump gas and little meth. timing is at 26 as well. So whoever said heads don’t make much difference btw my torque was 660ish. I stil dont get how come i am seeing just as much boost as he does with a bigger pully and better heads?! Can some one try to explain? Either way man...awesome numbers...time for some better heads though

 

Correct me if I'm wrong but you have a D1 (Oil fed) and Call911 has a D1SC which have different internal step up ratios. You're spinning your impellor much faster.

 

What type of intake and exhaust do you have? Also, what sort of filter and inlet tubing do you have?

 

Are you sure because of the step up ratio difference he's not spinning it slower?

 

You are correct, kinda.

Saint: The D1 has a step-up ratio of 4.44:1, where the D1SC has a 4.10:1. That is why you're making the same boost with a bigger pulley. Assuming you are spinning your engine to 6500 (same as Call911), your blower is turning 59,670 rpm versus his 59,962. Nearly identical.

 

I know I could have made more power with a smaller cam and better flowing heads, however the goal wasn't really to achieve max hp on pump gas, but rather to find the peak RWHP that my suspension would keep hooking up on the street and track. Believe it or not, I hook up still even at 614 at the wheels. I think if I were to change to some better flowing heads or go with a smaller cam to up the power to saints level, I would be all over the place traction wise. As fun as that can be, I would be extremly upset getting beat by someone with hundreds less HP but traction.

I am happy were my car is at. xxsaint69xx makes an excellent example of how heads and cam can make a big difference even between aftermarket and different aftermarket setups. Killer power man, I bet that thing is a beast!

 

Edelbrock LT4 straight out of the box, 3 inch ypipe with a gmmg out back..for inlet on the dyno i was using the POS plastic intake with a 14inch Green filter...since then i upgraded to a 4inch metal pipe thanks to lisa33

Car is now making 16-17psi...so hopefully with a 3.4 pull ill be over 18psi, also goin with 3 inch true duals....ill be very pissed if i dont his 800rwhp

 

You still on pump gas? What intercooler?

 

i was just pointing out how huge of a difference a nice set of heads can make not bashing your numbers at all I wasnt really 100% sure that heads made that much of a difference, but now i am a believer..btw..my car dead hooks in 2nd on the street with 315 nittos (13psi) at low rpms...right before i hit 3rd sometimes i get little tire spin, but i cant complain..i dont think there are many cars out there that can touch my car from a slow speed roll atleast not where i live ehhe

 

hahaha..thank you for making it clear to me..i feel like such a dumbass..i totaly forgot about the D1s steeper step up ratio.

 

OK, I did this quickly in my head before, now I see.

D1SC - Crank pulley/blower pulley X 4.10 X Engine RPM = Impeller speed

7.65/3.40 X 4.10 X 6500 = 59,962


D1 - Crank pulley/blower pulley X 4.44 X Engine RPM = Impeller speed

7.65/3.70 X 4.44 X 6500 = 59,670

 

I can open up WOT in 1st and still hook up! It will leave lines between shifts through 3rd, but its amazing having this power level, and being able to use it in 1st gear still!

I can definatly see how basically another 85 RWHP can be almost impossible to hook up in 1st on street tires. Still, I agree that there is little on the street that would be able to hang with you from a roll. Do you have any video of your beast?

I am going to be taking a bunch pretty soon of mine.

 

Car sounds mean as hell! JD's is right down the street from my house too

 

Bryan from PCM's for less does a dyno day there once a month or so, and it was only about an hour drive for me, so it worked out really well.

Thanks for the compliment! I love how the cam thumps as it whistles