Jenson

iTrader: (32)

Just got done flowing my 821's. I only have a 4.03" so thats what I used.

Lift - IN EX

.100 106 48
.150 142 85
.200 172 116
.250 198 143
.300 231 171
.350 253 193
.400 276 213
.450 297 225
.500 314 230
.550 323 234
.600 324 237
.650 327 240

Usually, our bench is very stingy, as my stock 241's flowed 5% less than some other test I had seen. These look to be 5-10% over others. Im mostly just looking to improve them and share my results with you. First I'll work the bowl, then exhaust, then the intake. Should take a week or two.

ChucksZ06

iTrader: (9)

Looking forward to your results. I did similar with mine but no flow results...so your info will be great. Mine are on ls2 block so 4.03 is representative on my app.

Jimbo1367

isn't that more than typically published? esp. at 0.300 lift

smok'nZ

iTrader: (160)

my TEA L92's flow 242/184@300 and 360/283@600 so im interested to see what yours end up flowing

Jenson

iTrader: (32)

Wow those^ really take off up top. Yes mine seem to flow better than typical, just differences in benches, pressure, temp, and all that jazz. Or maybe the different casting's. They are not to far off Richard from WCCH's stock #'s (different casting #'s):
https://ls1tech.com/forums/generatio...flow-data.html

Patrick G

iTrader: (14)

Your flow numbers from .300" up are within 2 cfm of what Richard@WCCH got on his flow bench with stock L92 heads. If you happen to pour the port, it would be good info to have the port volumes for intake and exhaust before and after porting.

WKMCD

iTrader: (2)

I'm running Richard's Stage 3 L92's now. He has them flowing 380 on the intake side - of quality air.

G8-4-speed

iTrader: (1)

I wouldn't be too concerned with what they flow stock as much as what they gain ported using the same bench. Just like what you were saying before ie. benches, pressures, temps, ect...The intake is tricky since they have such a wide cross section in the throat already. You can hurt flow faster than you can find it if your not careful. It will be intersting where you find your flow at.

danf1000

iTrader: (2)

I put around 10 hours on the exhaust side only of a set of l92s in a G8 GT 418 CI. Then run them for 3k and pulled them off. My polishing up to 400 grit eliminated carbon buildup on the exhaust port walls. it was dramatic and convincing, considering this part of the work took only around an hour.

Jenson

iTrader: (32)

And apparently I screwed that initial test up...oops. The .05 is really .100 lift, thats why they look so strange. My mentor/buddy is now doing the flowing for me as he guides me on what to do/not to do. He wanted me to start on the intake instead of the exhaust

So far this week has been uber crazy and Ive only done a little bit, 3 minimal cuts have yielded this though

.100 72
.150 110
.200 155
.250 193
.300 233
.350 249
.400 284
.450 294
.500 312
.550 324
.600 326


That is step two, step one was:

.100 70
.150 109
.200 151
.250 188
.300 220
.350 245
.400 269
.450 289
.500 307
.550 320
.600 322

It quits flowing at about .625" lift. Next will be a little valve mod and making it flow above .450!!

Jenson

iTrader: (32)

A few more little cuts this weekend to end up with this;

.100 71
.150 110
.200 157
.250 196
.300 226
.350 248
.400 275
.450 300
.500 317
.550 332
.600 331

G8-4-speed

iTrader: (1)

Still messing with valve angles? Is that a 50 degree seat? By the number shift it kinda looks that way.

Jenson

iTrader: (32)

Havent touched the seat yet, havent measured it yet either. That last one has a small little 15* cut between the seat and back angle, plus minimal porting. Hopefully I should be able to get to some hoggin tonight.

So he got bored today and ground on the head a little. He cut out the hump for the valve spring. It looks like its scrap to me, but a lot of the cnc programs do this too. Is it safe? The casting has maybe .125" there by the looks of it;

69LT1Bird

iTrader: (1)

I have a request. With the valves on the seats, can you put a straight edge on the head surface and measure to the edge of each valve? I was looking for that spec for my Performance Trends software.

Here are a couple of cross-sections from the blueprints for the L92 head. You can see how thin it is on the intake port near the spring pocket.

G8-4-speed

iTrader: (1)

I didn't pick up much getting rid of any humps. It seemed most of my money was in the short turn area. It didn't seem to respond to much guide or bowl work either. BUT, I started with short turn work and anything else I did after that was a wash or hurt it. I don't know if bowl work would have returned benefits if I had started there first.

Jenson

iTrader: (32)

Yea, I can do that bird. Still working on getting the port CC'd too. It looks like I still have about .165" left after removing the hump. It only picked up 2-3 cfm.

Jenson

iTrader: (32)

Sorry its been a while since I had time to mess with this. Did you want a measurement on say 4 points? 5 points including the center? Im going to do some more cutting tonight so I can measure what you want first.

Did some cutting again last night to the intake, and a little on the exhaust.

lift IN EX
.100 74 56
.150 112 95
.200 157 125
.250 196 154
.300 226 182
.350 252 205
.400 283 220
.450 306 230
.500 324 236
.550 337 240
.600 341 244

69LT1Bird

iTrader: (1)

4 points would be good enough. Thanks for the help.

Jenson

iTrader: (32)

Measurement 1, is the valves closest point to the deck, 2 is the middle of the valve, measured at its edge, and 3 is its point furthest from the deck opposite measurment 1. 4 is to the center of the valve.

EX:
1) .175
2) .365
3) .575
4) .555


IN:
1) .075
2) .385
3) .675
4) .500

69LT1Bird

iTrader: (1)

Have these been milled or are they stock?

...and thanks for the information. I appreciate it.