Horsepower in stages question.

[Vette73]

Went from stock on my 91 to headers and exhaust and Haiback chip...Few months down the line I had the plenum, I/Hs and air horn ported by Pete, 36 mm.......At each stage I felt a definate increase in power....

Right now I'm 382 RWHP......I'm thinking of porting the heads to 36 mm , Fidenza flywheel, secondary delete, and cams degreed.....

Of course this final step is the most costly due to the time and labor involved....My question is - by doing the " final stage" so to speak is there a significant increase in power and seat of the pants feel? Anybody ever did there mods in stages like I have? If so, was the final stage of porting the heads, degreeing the cams and adding a Fidenza flywheel worth it?

Thanks.....

[XfireZ51]

Originally Posted by Vette73

Went from stock on my 91 to headers and exhaust and Haiback chip...Few months down the line I had the plenum, I/Hs and air horn ported by Pete, 36 mm.......At each stage I felt a definate increase in power....

Right now I'm 382 RWHP......I'm thinking of porting the heads to 36 mm , Fidenza flywheel, secondary delete, and cams degreed.....

Of course this final step is the most costly due to the time and labor involved....My question is - by doing the " final stage" so to speak is there a significant increase in power and seat of the pants feel? Anybody ever did there mods in stages like I have? If so, was the final stage of porting the heads, degreeing the cams and adding a Fidenza flywheel worth it?

Thanks.....

I have news for u, it's not "the final step".

[G8nightman]

Lol thats just the tip of the ice berg before it really starts to hurt your wallet...

[Vette73]

Originally Posted by G8nightman

Lol thats just the tip of the ice berg before it really starts to hurt your wallet...

lol...Yeah I hear you...The "Final step" before cams
Added displacement and such.....Just wondering if any of the members
Did it in increments and when the head porting was done did it make
A difference.??

[XfireZ51]

I think I have a dyno chart showing 3 different stages of mods.

[efnfast]

I did mine in stages. Cams just arrived the other day. When they go in, the heads will also get ported. Between the heads and cams, I better feel a differance, I'll let you know.

[Vette73]

Originally Posted by efnfast

I did mine in stages. Cams just arrived the other day. When they go in, the heads will also get ported. Between the heads and cams, I better feel a differance, I'll let you know.

You should def feel the difference.....Heading out early tomorrow to Dempseys shop.....He's about 255 miles from me.....We been kicking things around over the phone for a few weeks but nothing like getting the feel for the shop and talking face to face....

I met Dempsey at Carlisle and he came across like a stand up person so would like to give him my business.....Seems to have a wealth of knowledge with the LT-5....

[XfireZ51]

Comparison of dyno results for power increases achieved in stages.


Green Line -Top End ported + Fidanza w headers Tune by Dominic

Blue Line - Addition of Pete Intake Cams + GVD Ported Heads Tune by Dominic

Red Line -Addition of Pete Exhaust Cams Tune by Dominic

[Vette73]

Originally Posted by XfireZ51

Comparison of dyno results for power increases achieved in stages.


Green Line -Top End ported + Fidanza w headers Tune by Dominic

Blue Line - Addition of Pete Intake Cams + GVD Ported Heads Tune by Dominic

Red Line -Addition of Pete Exhaust Cams Tune by Dominic

Hey thanks so much for info....

[efnfast]

My results to date:
Stock - 311 RWHP
Headers, exhaust, chip - 353 RWHP
Ported plenum and IH, chip - 397 RWHP
165 thermostat, 15 pound flywheel - no new dyno.
Next, cams and ported heads. And a custom tune.