Ron@Vengeance

iTrader: (51)

This isnt an EXACT A/B comparison... There are several differences that will be noted below. I just thought this might be useful to those considering the L92 combos over cathedral port combos.

Car is a 2005 GTO M6 with the following Modifications:

*Engine is a SDPC Built 416 L92 Shortblock-Callies Crank/Rods/Flat Top Pistons.
*Kooks 1 7/8 Longtubes with catted connection pipes
*Stock Catback
*ASP Pulley
*Textralia OZ700 clutch kit
*Walbro 340 Intank w/LPE Boost Pump

Original Top End Included the following:
GM L92 Cylinder Heads- Milled to achieve 11.72:1 compression
Custom Camshaft 238/246 .6XX/.6xx 113 LSA
GM L76 Intake Fully Ported by Vengeance
LS2 Throttlebody Fully Ported

New Top End Includes the following:
AFR 225 Cylinder Heads- Milled to 11.24:1
VRD Custom Camshaft -239/243 .624/.624 114 LSA (LSL Lobes)
FAST 92mm Intake Ported by Vengeance
Same LS2 TB

Red= AFR Combo
Blue= Ported L92 Combo





24rwhp Gain/32rwtq Gains with LESS COMPRESSION/SMALLER CAMSHAFT. Also, note the power under the curve has improved almost everywhere with the new combo.

Customer always said the old combo was a bit much. The heavy GTO didnt like alot of timing with the big compression and the car had small issues with drivability. With the new combo the car runs absolutely perfect, accelerates HARD thru the RPMs and makes more power everywhere!!!


Big Thanx to Tony Mamo @ AFR for a kick *** set of cylinder heads!!!!

Ron

MeentSS02

iTrader: (11)

...and thank you for sharing these results. Hopefully this thread doesn't turn into an L92 vs. * pissing match.

cyclerage

iTrader: (59)

Nice comparison!
Even if it does turn into a pissin match, it shows true results of two different setups that the average person can acquire.

JS

iTrader: (4)

I knew it all along

Hennytime

iTrader: (33)

great comparison. ive heard left and right that after 6200rpms or so the l92 intake wants to fall on its face, did the porting help that at all or is it just a straight myth?

edcmat-l1

iTrader: (10)

Nice results with the AFRs, but the results with the L92s are weak for that motor.
We've made close to that with a 6.0 and L92s. And made close to the AFR numbers with a 403 and L92s.
A better comparo would have been heads only.

edcmat-l1

iTrader: (10)

Looks like the L92s were all done at 5800.

94 guy

iTrader: (125)

the cam seems on the big side for the l92's?

Hennytime

iTrader: (33)

ya i didnt look close enough at the graph, lack of sleep...

venom ws7

iTrader: (13)

Thanks alot for sharing Ron.

AFR is the best heads out there period.

95FbFormula

iTrader: (25)

Nice comparison to those who are building a motor. Only thing I really don't like the the intakes would have been nice if they were tested on a single plain to get better numbers seeing as the fast is far more superior then the L76. either way good results for both ends

ExTurbo

nice comparo, but honestly i think a nice chunk of the gain in power is a result of the better intake. The drivability and down low tq are the AFR's all the way

ls2 bait

iTrader: (11)

this interested me. im going to be using a tfs 215 on my 416 but with a larger cam. if it makes those kind of numbers i will be a happy happy man.

DrkPhx

iTrader: (15)

Interesting comparison. The AFR setup makes 45 rwhp more at 6500 rpms. That's a huge difference that will pay dividends at the track.

ExceSSive

iTrader: (13)

Thanks for sharing the results. It is about what I expected though.

slow trap

iTrader: (22)

what kills the l92 setup is aparently the l76 intake. i think this is a great comparison because alot of people use that intake instead of the victor jr / single plain style. it is either get a set of heads that flow their *** on paper but choked down eith a sub par intake or get a good set of heads with a good intake and make more useable power. if cost comes in you can easily get a budget ls6 style head to break 500 rw,especially with 416 cubes. i do agree however, the results from the l92 setup in this build seem less than stellar,i would have changed setups also.

DocEwww

iTrader: (1)

Thanks for sharing. I look forward to seeing what ported L92s can do with FAST L76 style intake if it ever happens.

Ron@Vengeance

iTrader: (51)

Less than stellar?? Or not over inflated?? Read above guys, this is all happening thru a STOCK CATBACK/Cats/Stock Waterpump etc etc... The L92 set up was built almost a year ago to the day. At that time there wasnt alot of experience with the L92 setups out there. We could get the car to break 500 on a perfect day, but that was it.


I posted this to be informative. I stated above that this wasnt an EXACT comparison. Its simply something that was done here at the shop and I felt the information could be useful to some of you considering different options..

Remember, the AFR combo has OVER a half point LESS compression/smaller camshaft and makes MORE power EVERYWHERE.... Just something to chew on

Johny GTO

ROn, thanks for posting your results. i unerstand you werent trying to compare heads, just showing results.
thanks and keep it up. makes for good reading and nice real world results.

CougarL92

iTrader: (6)

What were the flow number on the L92 heads after porting? Those numbers seem way low for that setup.. I hit 533 RWHP 6 spd car with a 416 ci and a similar size cam,w/ TEA ported L92's almost a year ago with hardly any tuning done.. Now have a new combo that will be done here in the next week or so w/same heads on a 427 ci with alittle more compression and better headers to see what the diffrence is..