PwrdbyLS1

iTrader: (5)

I want to share my flow numbers of my ported L92 heads and with my LS3 ported stage 2 intake by JeremyF. The heads have been hand port by a local experimented porter.

Stock #s ( I / E )
.100 75 56
.200 151 115
.300 214 155
.400 268 182
.500 294 202
.600 320 204

Ported #s ( I / E / LS3 I)
.100 70 56 73
.200 155 119 156
.300 230 172 222
.400 280 205 265
.500 320 228 290
.600 344 236 307
.650 352 238 312
.700 358 242 318

Runner: Intake ~272cc Exhaust 88cc Chamber 71cc

All flow test were on the same bench with 4.000 bore. I was hoping more cfm with the ported intake but it seems all plastic choke L92 heads...

Heads will be mill .030" to reach around 65cc chamber to have around 10:1. This setup is gonna go on my LY6 short block with a PatrickG custom cam. Hoping between 475-500 rwhp with the 6.0L. Next I'll build a 408 with same setup with around 11:1.. can't wait !

Here's some pictures




The LS3 ported stage 2 with PP fuel rails with my custom brackets to fit my EV1 injectors

And I want tu know if its normal that seals don't sit on the springs seat.


Tell me what you think !! Thanks!!

RyanSws6

iTrader: (72)

You may be in the 475 range. I have something very similar to what your plans are. This includes a new ported LS3 stage 2 by Jeremy. I have PRC heads with hollow valves milled .030 with .030 cometics for my 11.1 CR. I did have Patric G also spec out a cam for me. The cam that made 500rwhp was from my Ls6 head setup. I've yet to slide in his new cam. I'd like to go to a new tunner when I slide it in. I'd like to consider a fast102 but I'm not sure if its worth $$ for an extra 10hp over the ported LS3.

My new plans are when I install the cam, I'm going to have Rich at WCCH port them even more.

LS1 BU

iTrader: (13)

Flow numbers seem real good. Heads picked up a ton on exhaust. Going to have my l92's ported. Just going to clean up the intake side and spend more time on exhaust side.

PwrdbyLS1

iTrader: (5)

Nice setup Ryan! You should pull 520 rwhp with thoses heads with a good tune. What are the specs of your cam?

Yeah numbers seems good, Can't wait to start this monster !

thanks

SweetS10V8

iTrader: (4)

Watch your Piston to valve clearance if on a stock piston motor.

RyanSws6

iTrader: (72)

Yeah need a better tune drivability not very good. My very near future plans is using Pats' cam and Rich at WCCH running his CNC program through my heads. I'd like more work on the exh side. I assume with the cam, head touch up, good tune, I should have over 520wp. I know I would hit the 510-515 range with adding a electric WP.

My current cam was for my Ls6 setup 240/244 108/113 114lsa. Pats' cam is a reverse split.

What I need to get out of my head is going 427 when I pull the heads.

99T/ATIME

iTrader: (3)

I considered the LY6 Block and ported L92 heads for my current build..... Do the 408 now and go with a Ported Fast Intake with that combo. A good cam and tune should yield 530-540 without issue.

SEMI-RETIRED

The flow numbers are within 1% of the WCCH/L92 stage 2 cnc heads for comparison unless they have changed there program.

Any idea what type of valve jobe was done if so what angles and what back cut on the valve?
Just would like to compare with some work I have done.
Seem like good numbers to me though should be close to your goal GREAT JOB!

hey forgot to mention the exhaust is 10cc smaller than the mention cnc heads.

WKMCD

iTrader: (2)

FWIW: Richard has done more work on the L92's and has increased the flow considerably. He should have my heads back any day now to run the new program through them.

Mikey 97Z M6

iTrader: (37)

Those flow numbers look very similar to a set of L92's I ported a couple years ago (still using them). I never had that engine (387) dyno'd but it ran the times in my signature with a stock unported L76 and an old school single pattern MTI Z1 cam.

I'll be curious to see what kind of hp numbers your 6.0l makes with these heads since my new engine will be an iron block 370 with the ported L92 heads. Looking for a cam now....

Nice work on the porting whoever it was.

Mike

SweetS10V8

iTrader: (4)

Everyone is "comparing" flow numbers like they are all done on the same flow bench. My flowbench says L92 heads flow 298cfm max, everytime. While others say tey flow 320+ out of the box. When Icheck my calibration with the Superflow checking plate, mine is within .5 cfm on every hole.

Flow numbers are like dynos. To truely compare, the heads need to be flowed on the same bench.

hymey

Those ex ports look great, High flow small exhaust port works well. I recently heard of a well known CNC head that had a valve guide break and lunched an engine. Good idea not to take to much from there.

99T/ATIME

iTrader: (3)

I Agreee

Mikey 97Z M6

iTrader: (37)

I agree to a point, and there are many factors that can change the flow characteristics of a flow bench. Did the operator use a pipe on the exhaust? What's the size of the bore used during testing? Were they both done at 28"? Was there a radius used on the intake runner and if so,,, how large was the radius? Was it a clay radius or steel plate etc... All those things play a factor. But, at the same time, you can see patterns where certain benches seem to correlate well to one another, just as certain dyno's will.

My stock unported baseline flow numbers (for the intake side) are damn near a mirror image of his stock unported basline flow numbers. But, my flow bench operator used a pipe on the exhaust side so my exhaust numbers are much higher. It's reasonable, in this case at least, to say that the ported flow numbers for the intake side are a good comparison. If my baseline flow numbers for the intake were skewed significantly from his, then obviously the ported numbers wouldn't compare at all.

My .02.

Mike

PwrdbyLS1

iTrader: (5)

I don't have the cash right now for a 408. This is why I build this 6.0L.

I don't know what valve job was done to the heads...

I got my specs for this 6.0L.. A big cam that will work well on a 408
235/243 .621 .624 114LSA +2

I dont know how bad the drivebility can be will my 10:1 compression?
Like a stock LS1 with a Magic stick V3 ??

Do MLS 4.060" gaskets are available with .030 .040 thickness?

Maybe I would bump the compression a little bit to give me a better drivebility!

RyanSws6

iTrader: (72)

Hmm, those cam specs look interesting...mine is a bit different, not by much. It does seem a little large for a 6.0. I look to slide in the cam and redone heads in April.

PwrdbyLS1

iTrader: (5)

Finally I got this custom grind cam: 227/235 .639 .621 114+2 LSK/LSL lobes
Can wait to see results!