Small Block Head Flow Chart

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Okay numbers are in for the SBM CNC Shockers…intake only as the guy who is doing them just called me and I jotted down the numbers :

Lift. Advertised. Flowed.
200. 142. 123.3
300. 202. 188.9
400. 251. 236
500. 278. 268.5
600. 284. 282.
700. 286. 282.

He said the port has really good velocity…more to follow
 
Nice and thanks. The numbers are encouraging. His bench reads stingy by compare but looking at the numbers, the curve is very similar to the advertised numbers. This is more important that the actual numbers.
 
Nice and thanks. The numbers are encouraging. His bench reads stingy by compare but looking at the numbers, the curve is very similar to the advertised numbers. This is more important that the actual numbers.
He said the low numbers are bad…it will take a bit of pissing around just to get 200-400 up to advertised numbers
 
He said the low numbers are bad…it will take a bit of pissing around just to get 200-400 up to advertised numbers

those very important numbers at 400-500 are down significantly over advertised. That's where the valve is at a significant amount if time in a typical flat tappet bracket type deal
 
those very important numbers at 400-500 are down significantly over advertised. That's where the valve is at a significant amount if time in a typical flat tappet bracket type deal

A few years ago I watched one getting flowed at 400 to 700 and I remember it was a bit low…but I was surprised how off the low lift was down…saying that lots of guys here have made 550 to 600 hp with them
 
Okay numbers are in for the SBM CNC Shockers…intake only as the guy who is doing them just called me and I jotted down the numbers :

Lift. Advertised. Flowed.
200. 142. 123.3
300. 202. 188.9
400. 251. 236
500. 278. 268.5
600. 284. 282.
700. 286. 282.

He said the port has really good velocity…more to follow

check this post out.
Racing flow benches

maybe ask the guy that flowed your heads if he knows what a stock port LA edelbrock head flows on his bench.
 
Considering it will be from the same bench, I have no issues with that. Looking forward to the race!
I might see if he will flow some stock W9 heads next week…they will probably kill the Promaxx heads even as cast
 
Dam it must have taken a massive effort to compile all that data.
There are some numbers listed for the standard 340 iron head which could be an X heads. If true the air flow numbers are a lot higher then I would have expected 189/142 @ .600



usually it will have valve size and if ported who did it. I don’t hold it as gospel but it does give you an idea. And yes he did put a lot of work in that.
 
Okay numbers are in for the SBM CNC Shockers…intake only as the guy who is doing them just called me and I jotted down the numbers :

Lift. Advertised. Flowed.
200. 142. 123.3
300. 202. 188.9
400. 251. 236
500. 278. 268.5
600. 284. 282.
700. 286. 282.

He said the port has really good velocity…more to follow

Talked with the head porter last night for a bit...said he now has the lower numbers back in the advertised area... and the upper numbers in the 294 range with really good velocity...intake volume is in the 190 range...he said when you take them out over 300 the port turns into a toilet...
 
Okay here are the numbers

Intake

Advertised. Flowed. Ported

200- 142. 123. 139
300- 202. 189. 201
400- 251. 236. 244
500- 278. 268.5. 270
600- 284. 282.4. 292
700- 286. 282.6. 293

Exhaust

200-124. 98.5. 108
300-158. 135.4. 146
400-190. 169.9. 182
500-203. 200.7. 211
600-219. 218.4. 229.9
700-231. 223.8. 242.3

These tests were on a 4.070 Bore FYI
 
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Anybody got a good set of SBM B-1 BA heads or B-1 BA M/C heads with some flow numbers. I have a bare set of M/C heads waiting to get done.
 
Stock RHS/Indy LAX head 1.94 intake/1.60 exhaust no tube......

.100 57/52
.200 124/105
.300 184/143
.400 230/163
.500 255/167
.600 257/167

Ported RHS/Indy LAX head 1.94 intake/1.625 exhaust w/1-3/4" tube......

.100 NA/NA
.200 144/131
.300 191/173
.400 234/201
.500 264/222
.600 280/236
.700 283/238
462 HP on a big bore 292ci/273

Ported RHS/Indy LAX head (8 cylinder avg.) 2.055 intake/1.625 exhaust w/1-3/4" tube......

.100 NA/NA
.200 145/124
.300 206/176
.400 253/214
.450 275/226
.500 290/236
.550 301/242
.600 303/248
.650 297/253
With these heads a 360/424 single 4-bbl stroker made 474 LB-FT @ 3,000 rpm, 574 LB-FT @ 5,100 rpm and 629 HP @ 6,400 rpm. Solid roller 258/260 @ .050, .660/.668 w/1.6 rockers, 110 LSA, 107 ICL and 91 octane pump gas from the Stinker Station.

Very nice numbers - I need those JEWELS
 
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