i think i've finally decided to go with a head/cam pkg(thunder racing cheatr). this will hopefully put me close to 400 hp along with a tune. that being said, what other mods(if any) to the drivetrain would i have to make to support the extra hp. i have a stock 98 a4 z28 2:73's in the rear....p.s...can someone out there let me know if any of u out there have any other economical suggestions for a h/c pkg.....thx

 

what are the specs of you cam? a stall and some 3.73 will make your auto rip out of the hole.

 

I think the cheatr cam is too small IMO.

To take FULL advantage of those heads you need to find a combination of stuff that works together.

For instance look at the total CFM flow of your heads at .600 lift depending on what "stage" they are they may flow from 275-310 cfm etc. at .600"

Now find a cam with a lift close to .600, for instance my cam is a TSP Torquer V2 and has a maximum intake lift of .595.

More air in= More air out=More power.

The duration should be whatever you feel necessary, the higher the duration the higher your gonna have to spin through the RPM range to make power. If you lower your LSA with the intake center line(mine is 112+2) it will help bring your power band down sooner so you can get to your peak power faster.

I can go on and on.

My suggestion would be

some Stage 2.5 5.3L heads with a TSP Torquer V2(yes I may be a lil biased but this cam is fantasticand make lots of power while still being very streetable)

That package will be good for around 400+ rwhp on an automatic.

The only thing I can think of to modify your drivetrain to "up" your hp would be a stall converter.

 

+1

 

I'd say torque converter and gears also. Maybe port and polish the T/B. Do you have long tubes or stock exhaust manifolds?

 

With my '02 Formula, stock stall and 2.73 gears, so this will be pretty close... my mods: Lingenfelter's GT2-3 (207/220 @ 118.5°) and Stage I LS6 heads (~11.0:1 CR), a lid, throttle body, long tubes with cats, and SLP dual/dual.

Power... with just the cam and stock tune I made 344 rwhp and 336 rwtq on a Mustang dyno ~52 feet above sea level. Lingenfelter promised a 50 fwhp gain with the heads I got.

As far as "economical"... I get about 24.73 miles per gallon with the heads.

 

First you want to get all the boltons, intake and exhaust, before you get Heads/Cam. That will help your engine breathe, and better prepare for heads/cam.

A lot of people are going to tell you to first get a stall converter, but personally I'm not a fan of them. They take away from the rpm feeling and make the driving experience too 'sloppy' imo to be worth it. Ymmv. If you get a stall converter, you want to also get a tranny cooler, those two mods go together.

As far as what heads cam kit, look into Futral, they are a sponser here and have very good performing cam kits. TSP is also a highly recommended shop because of their performance and budget oriented combinations.

 

I would go with exhaust and intake first otherwise you wont realize the full potential of the h/c package. I would also recomend a slightly larger cam. My car has the TR230 cam and it put down 430 rwhp with all the other mods in my signature minus the Fast 90/90. After you get those mods I would recomend a good converter.

 

thanks for the input guys! looks like i'll be going with afr heads instead...i know i'd like to go the economical way and start with some lt's, but it's a guaranteed 'fail' for the smog test here in cali. so i figure the safest way to go is h/c to keep it street friendly and gain some major hp. not taking it to the track anytime soon. kinda just wanted a street sleeper. i'm probably gonna get 3:42 gears and some subframe connectors in the near future....afr heads + cam + tune = $4800?