First I am going to start of with some history:

I purchased a 1991 from a previous forum member. The car had 222,000 miles at the time of purchase. Approximately 2 weeks after purchasing the car, I installed flowmasters and a high flow main cat. Approximately 2 months after the purchase I decided to replace the L98 with a crate motor. I decided on a Fastburn 385. With this purchase I also changed the intake to a Miniram III with a 58mm throttlebody. At the time of install, I had the motor dyno'd. The new motor was putting down 254 RWHp with 299Ft-LBS of torque. Approximatley 6 months after purchase I had the transmission rebuilt and installed a 2400 Stall torque converter. I am currently in the process of reinstalling the entire rear end with a 3.54 gear ratio (I removed the diff, batwing, spindles, brakes and etc).

I need some help in planning the next mod to accomplish over 300RWHP. I will be using the car a weekend cruiser and would like to maintain cross country comfort if I so desire to make a drive. I currently have the stock exhaust mainfold with pre-cats. I am planning on long tube headers so I need help beyond headers. I expect the headers will get me to approx. 270-275 RWHP. The Fastburn 385 is marketed with a upgrade to the Hot Cam and 1.6RR which supposedly increase the crank HP by 25-30. I have also looked at the LPE 219 cam. Unfortunately, I do not know the flow numbers for the aluminum fast burn heads so I do not know where my largest restriction is. Any help or advice is greatly appreciated.

 

The first thing I would do is change to an aggressive cam, then have the heads ported and larger valves installed, then do the headers.

But I would expect the 385 to put out closer to the advertised 385 with the MR on it, so it should be in the 310-320rwhp range already. The fastburn heads have a 210cc intake port, i think.

If you dont have a custom chip, there may be a good bit of power to find there.


[Modified by vader86, 11:15 PM 7/25/2003]

 

Maybe you need some tuning, and I think the 58mm TB is just a bit much. You can LOSE horsepower with too big of a hole up front.

:withstupid: I think you're about 100HP shy of what you should be putting out already, it just *seems* like there's a major restriction/flaw in the system to be worked out?

G'luck though. :thumbs:


EDIT: When you dyno'd the car, did you get an Air/Fuel readout as well? If you weren't right around 13.4 a/f or so (realistically 12-14), you're probably losing power.... but there are others who can detail this better than I


[Modified by Ramanstud, 11:40 PM 7/25/2003]

 

I forgot to mention that an Ed Wright Chip was installed with the crate engine. However, I only picked up around 5 HP with the chip. I also had an MSD distrubutor with remote coil installed

 

Was the dyno a Mustang or Dynojet?

 

Well, I'm not doubting the Ed Wright chip... all I'm saying is that it may have worked out for your system and you're just not getting expected results (what will happen when I take mine to the dyno... :lol: )... OR the chip is generic enough to where you're still not optimal at WOT.

And who knows, it might not even be related to the programming much less anything else. Just tossing out some ideas to see if we can figure out why the fast-burn "385" isn't putting out more power with an unrestricted intake like the Miniram. Because honestly those numbers I would expect from a TPI unit. Then again I'm an idiot, so take it with a grain of salt! :lol:

:thumbs:

 

I believe it was a Dynojet

 

TPiS has an engine on their development page, which has Fastburns and a ZZ409 cam, that is putting out 460hp and 437tq. Granted its a 360ci, but thats not much difference.

All I think you really need is a cam change and a smaller TB. But you should be putting out good numbers right now, If you can invest in a good dyno test/tune session, you may find something is up with your A/F ratio or something else.