how many people on here have actually had their heads flowbenched?
#1
how many people on here have actually had their heads flowbenched?
Just wanted to know if anyone has actually had their ported ls1,ls6,or 5.3 heads flowbenched after they bought them to see if they really flow what they say. I recently bought a set of 5.3 heads that were supposed to flow well over 300cfm but they only flowed 296. At first i was a lil dissapointed but the guy that flowed them said that is actually pretty good compared to the other ported factory castings he has seen. Believe it or not however he actually put a set of ls1 heads that he ported up there and they outflowed mine up until .400 inches of lift and the average cfm was higher and they only had a 217cc runner. Well anyway i would just like to see other peoples results. Also do certain flowbenches flow less?
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Different benches flow different yes. They should all be within 5-10 CFM. The bench itself can also leak a little, and give different results. I have flowed some of the stuff that I ported, but never other people's work that I knew advertised numbers. Also, if they were hand ported they may vary 5-10 CFM from port to port.
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so wouldnt your heads be better for that cam since it will be a higher rpm cam with higher lift number anyway? his heads are fine for a low end torque monster. My heads got flowbenched at TSP and they said they flow 310cfm at .600 lift I figure give or take 10 cfms that is still pretty good for the money. I wouldnt worry about what they really flow unless you got promised like 25 cfms higher than what you really got.
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#8
so wouldnt your heads be better for that cam since it will be a higher rpm cam with higher lift number anyway? his heads are fine for a low end torque monster. My heads got flowbenched at TSP and they said they flow 310cfm at .600 lift I figure give or take 10 cfms that is still pretty good for the money. I wouldnt worry about what they really flow unless you got promised like 25 cfms higher than what you really got.
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my ETP 225s flowed a little lower than advertised on the int...but the bench was known to be a bit stingy
Advertised
Lift Int Exh
.100" 71 57
.200" 153 114
.300" 208 164
.400" 265 204
.500" 308 224
.550" 320 228
.600" 328 231
.650" 332 234
.700" 320 236
Actual:
.200 138.30 110.21
.300 214.30 160.68
.400 266.40 206.36
.500 302.54 222.37
.600 320.76 231.00
.625 327.09 -
.650 306.50 -
Advertised
Lift Int Exh
.100" 71 57
.200" 153 114
.300" 208 164
.400" 265 204
.500" 308 224
.550" 320 228
.600" 328 231
.650" 332 234
.700" 320 236
Actual:
.200 138.30 110.21
.300 214.30 160.68
.400 266.40 206.36
.500 302.54 222.37
.600 320.76 231.00
.625 327.09 -
.650 306.50 -
#13
I have flowed alot of "330" CFM heads that barely mustered 310 (and some worse)....and some in the "low 300's" (so they were told) that were in the 280-285 range and occasionally worse. Not to mention there is alot of inflated exhaust numbers out there as well. The BEST LSx exhaust ports I have seen flow in the 250 CFM range at .600 lift....some are advertised significantly higher that flow in the 235-240 range (on both of my flowbench's....an SF600 and the one I built which I do most of my R&D on).
Welcome to the "real world" guys....LOL
Its good to independently check them....a small price to pay to insure you wont be chasing missing horsepower for a year scratching your head why.
Im sure you guys have seen my "flowthread".....that was posted to show you guys what the largest runner best cathedral port heads actually flow on the same piece of equipment with all the same flow fixtures, exhaust tube, etc. While the names have been withheld for obvious political reasons there is alot to learn from that information and it represents a ludicrous amount of time in total.
The bottom line is unfortunately most heads flow below advertised....some are just worst offenders than others and a small percentage are close to their published figures. When the 205's were first released we caught alot of crap about the fact they "only flowed 300 CFM", when the reality was at the time few heads regardless of their size actually did that (and the ones that did were 20-30 cc's larger).
BTW, AFR guarantee's our heads flow within 2.5% of our published figures (there has to be a small tolerance for production issues such as cutter life, CNC rotary and spindle conditions, etc.). Some actually flow more than we advertise....but in general our published figures are very close and most shops without an axe to grind with our company will verify that.
In short....Everyone serious about making power should have their stuff verified. Its the only way to really know and I include our product in that statement as well. In our case if something is wrong (unlikely but occasionally it happens) we will stand behind it and either get your head up to snuff or replace the casting.
Im off to PRI....will follow up with this thread later.
Regards,
Tony
Welcome to the "real world" guys....LOL
Its good to independently check them....a small price to pay to insure you wont be chasing missing horsepower for a year scratching your head why.
Im sure you guys have seen my "flowthread".....that was posted to show you guys what the largest runner best cathedral port heads actually flow on the same piece of equipment with all the same flow fixtures, exhaust tube, etc. While the names have been withheld for obvious political reasons there is alot to learn from that information and it represents a ludicrous amount of time in total.
The bottom line is unfortunately most heads flow below advertised....some are just worst offenders than others and a small percentage are close to their published figures. When the 205's were first released we caught alot of crap about the fact they "only flowed 300 CFM", when the reality was at the time few heads regardless of their size actually did that (and the ones that did were 20-30 cc's larger).
BTW, AFR guarantee's our heads flow within 2.5% of our published figures (there has to be a small tolerance for production issues such as cutter life, CNC rotary and spindle conditions, etc.). Some actually flow more than we advertise....but in general our published figures are very close and most shops without an axe to grind with our company will verify that.
In short....Everyone serious about making power should have their stuff verified. Its the only way to really know and I include our product in that statement as well. In our case if something is wrong (unlikely but occasionally it happens) we will stand behind it and either get your head up to snuff or replace the casting.
Im off to PRI....will follow up with this thread later.
Regards,
Tony
#14
TECH Senior Member
And that is the "Blue Pill" of reality
Just to add, you get what you pay for, sometimes the extra $$ spent is really worth it.
One of my favorite wisdom is as Tony mentionned:
1- Have your heads flowed independently
2- Always inspect your products thoroughly
3- Only choose your cam once the real flow numbers are in your grasp
Mark
Just to add, you get what you pay for, sometimes the extra $$ spent is really worth it.
One of my favorite wisdom is as Tony mentionned:
1- Have your heads flowed independently
2- Always inspect your products thoroughly
3- Only choose your cam once the real flow numbers are in your grasp
Mark
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#18
thanks for all the info guys..now that i see the flownumbers others have had i see that my results are actually pretty good..I figured that they wouldn't flow what they claim but i thought they would at least be a lil over 300 but i see now that 296 isn't all that bad. Also tony that is a great thread you have on the flow numbers.