430-435 CHP now.....What can I do to get 500-510 CHP?

[Vette73]

Right now I'm 382 hp to the rear at 7,000 RPM...

Headers, exhaust , Chip,ported plenum , air horn and I/Hs ..
What can I do to bring this 91 to the 500-510 CHP?

I'm located in NY....Sent Pete an email this morning asking for his advice
since he did my porting..I know port matching the heads will give me more power, yet I don't do that type of work....

Any idea of the cost this might be to accomplish 500-510 horsepower at the crank ? I know Marc has a 510 package but my car is already modded with what I described above...

I was thinking of going to Vette Drs and picking there brain...
I heard stories that were good and bad about the place...

As far as labor, would it be easier to do head work by taking the entire motor out to get to the heads or,just breaking down the motor while its in the car?

[George Maz]

http://www.zr1.net/forum/showthread.php?t=26300
Hib has a 93-95 chip for sale. I'm not sure if it would work for a 91 without head porting. I'm surprised a California owner hasn't already purchased it considering the adjustment made to help pass emissions.
Otherwise, take a ride to Stafford VA and Dyno-tune at the new shop. You can always have Marc burn a chip with the modification info you send him.

[G8nightman]

Get a light weight fly wheel it should help you on your hp quest.

[We Gone]

I have Marc's 510 with stock FW and cats right at 495HP, I would say get your heads done.

[Hib Halverson]

To get 500 SAE at the flywheel w. stock manifolds and cats you need:

Ported heads
Ported housings
Fully or partually ported plenum
Cams reset
Bigger injectors
Low restruction air filter assembly
Exhaust manifolds deburred internally with port entries blended.
Stock cats with cat entries deburred and blended.
Low restriction exhaust system w. 2.75" or 3.0" pipe
Aluminum flywheel
93-94.5 octane fuel
Proper calibration

With the above set-up, my engine made 416 SAE at the wheels on a DynoJet and, using the .82 correction for C4 manuals, 507 SAE at the flywheel. The exact power output depends on the dyno and a host of other issues unrelated to the engine itself. Many other engines with similar packages of mods have made 495-505-hp SAE at the flywheel.

If headers are legal in your state, given proper cal and exhaust system, their addition will get you to 510-520 SAE at the flywheel.

[FU]

The Vette Dr's really don't work on LT5's now.

[Vette73]

Originally Posted by FU

The Vette Dr's really don't work on LT5's now.

Nobody does.....Maybe I will drive it out to Petes garage and take Amtrak home...Lol.......Its free for me....

[Paul Workman]

Originally Posted by Vette73

Nobody does.....Maybe I will drive it out to Petes garage and take Amtrak home...Lol.......Its free for me....

Marc's Web site lays out the steps to get to 510 @ the crank.

Either Pete or Marc can get you there, and as Hib suggested, it is comprehensive; yeah the motor has to come out.

Once the porting is done, the cam phasing has to be optimized and the calibration none during a live dyno session. (In that regard every motor is unique enough that to get the most from it the tuning can't be "cookie-cutter" i.e., someone burning you a chip.

Worth it? Oh...Yeah! You get a power delivery across a wider rpm range like what you might expect from a lot more cubic inches! It transforms the LT5. You get the performance without sacrificing reliability or driveability.

[FU]

Being that the heads are off for porting install a bigger intake valve and larger intake cams. If you want to go fast.

[XfireZ51]

My motor has gone thru an "evolutionary" upgrade, with Phase 1 being ported top end and port matched heads + headers/tune(my own). That put it at
398+rwhp.

Phase 2 was fully ported (GVD) heads + Pete's intake cams + my tune
430something rwhp. Very nice combo. Smooth power delivery

Phase 3 added Pete's exhaust cams + top end port touch up + SW Xpipe w
DynoMax muffs. Again, my tuning both on part throttle driveability and WOT.
This combo did more for torque which just feels great. As much as I liked Phase 2, I would not go back. Idle is a bit rougher, but all is forgotten once in motion.
454rwhp/402rwtq.