View Full Version : Lightly cleaned up stock heads.. NICE gains!


YO-EL
06-02-2005, 10:17 PM
I just sent out a set of stock heads to be mildly cleaned up & gained 35 RWHP & 30 RWTQ.
I did NOT get a major porting job, just a mild clean up & blending of the bowls..
Red Run 25 is BEFORE cleaned up heads
Blue Run 31 is AFTER cleaned up heads...
Don't look at peak spike numbers....
Look at 6200 rpms...
HP from 353 to 388.4 (+35)
TQ from 294.7 to 324.2 (+30)

http://www.corvetteforum.net/c5/indypace78/hd2.jpg

Patrick G
06-02-2005, 10:53 PM
Extremely nice gains. Could you list the rest of your mods? Were the heads the only change? Any bump in compression by milling the heads? Congrats on your numbers.

YO-EL
06-03-2005, 07:41 AM
I have full bolt ons with the TR 224 cam.
Yes, the cleaned up heads were the only change from the red run #25 to the blue run #31..

MeentSS02
06-03-2005, 07:46 AM
That's a great gain. Bet you're happy.

Got Me SOM
06-03-2005, 10:00 AM
That's the kind of gains you want, entire gains throughout the rpm range, totally parallel with old curve. Car must feel great now.

BADSZ28
06-03-2005, 10:54 AM
Nice! What castings? What CR?

NOSjohn
06-03-2005, 11:13 AM
Very nice gains !! Who did the work? I might have to have a spare set sent out. Just curious why the extreme spikes (without nitrous) and hp/tq curves cross at less than 4,900 RPM ? Standard Hp/Tq curves should cross at 5,250...again, just curious, no flame meant.

SideStep
06-03-2005, 11:47 AM
Very nice gains !! Who did the work? I might have to have a spare set sent out. Just curious why the extreme spikes (without nitrous) and hp/tq curves cross at less than 4,900 RPM ? Standard Hp/Tq curves should cross at 5,250...again, just curious, no flame meant.


They don't really cross at 4900, if u look at each side of the graph you will see the scale is different for TQ compared to HP... It is correct...

Do you have a dyno-graph showing SAE???

:cheers:

JS
06-03-2005, 11:54 AM
Bad dyno results..
U dynoed unlocked which will skew # and its in STD....

Got Me SOM
06-03-2005, 12:09 PM
unlocked will show more torque, locked will show more hp, no biggie there.

std vs sae the power gains throughout the rpm range should be similar, the actual numbers picked up will differ but not by a whole lot.

BADSZ28
06-03-2005, 12:41 PM
Was there tuning involved?

JS
06-03-2005, 03:51 PM
I realize his number will rise on HP w/it locked and his TQ will drop as I've had a few fast F-cars (10.50's@126 and 10.80's@124) ;)

Realistically,I bet LOCKED in SAE his car woul pull somewhere around 395RWH/370RWT..
I'd love to see it re-dynoed in SAE/LOCKED to see if Im close....

YO-EL
06-03-2005, 05:13 PM
Joe:
Whats the difference in the #'s??????? I could care less about peaks....
Locked I was at 418 RWHP & 380 TQ
Unlocked 392 RWHP & 401 TQ
Big deal...
My only concern is gains under the curve,, +35 HP +30 TQ..
Ellis

JS
06-04-2005, 10:45 AM
Its better to tune it locked...
A4's are tricky in unlocked as they carry the power higher on the dyno,look at your unlocked peaks and you'll see what I mean but I do agree the power under the urve is where its at Ellis :D

I think I'm pretty close then,418 in SAE Correction would be right about 400RWH and your TQ in SAE Correction would be 365RWT.....

Your car is making GREAT power for such a mild setup...
Especailly threw an A4......

+35HP/Z+30TQ are actually in SAE Correction more on the lines of 32RWH/28RWT
Very impressive for 400.00 Heads Yo-El...

Now go run the car when it gets cooler out..
U have the power for 11.20's in that car on CCW's and ET streets

YO-EL
06-04-2005, 12:01 PM
Will be at E-town next Sat for the Corvette Challenge..
Come on along Joe!
Me & about 10 other guys from CCDV are running..
Even Dale went last time out..
Pro 8 event too...
Maybe even a 7 sec vette!

JS
06-04-2005, 12:08 PM
Maybe I'll come and let u beat up me in my 12 Sec GTO ;)