Ported heads complete
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Ported heads complete
I finished porting my stock L98 heads earlier this week, and got the car running last night. I will post pictures of the head work in a couple of days when I recover from the lost sleep.
For those who were curious, my flow numbers went from:
199 cfm @ 0.500" intake
110 cfm @ 0.500" exhaust
to
236 cfm @ 0.500" intake
142 cfm @ 0.500" exhaust
The head work consisted of gasket matching, unshrouding the valves, bowl blending, and a 4 angle valve job....no major port work.
For those who were curious, my flow numbers went from:
199 cfm @ 0.500" intake
110 cfm @ 0.500" exhaust
to
236 cfm @ 0.500" intake
142 cfm @ 0.500" exhaust
The head work consisted of gasket matching, unshrouding the valves, bowl blending, and a 4 angle valve job....no major port work.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Ported heads complete (CorvetteZ51Racer)
Just curious, what did you get the flow numbers with. Do you have a flow bench? Also you should know that .050" is a fine number to show flow, but what really matters is when you add up the .01, .02, .03, .04, and .05 lift. Any numbers on those other lifts?
The .050 is probably the least improtant one, since the valve is seldom at that point for very long.
I'm not busting your chops, just curious, I have been throwing around the idea of making my own flow bench, you know with all my free time :rolleyes:
Good numbers though :cheers:
The .050 is probably the least improtant one, since the valve is seldom at that point for very long.
I'm not busting your chops, just curious, I have been throwing around the idea of making my own flow bench, you know with all my free time :rolleyes:
Good numbers though :cheers:
Racer
Joined: Apr 2002
Posts: 415
Likes: 0
From: loughborough Leics ENGLAND
Re: Ported heads complete (CorvetteZ51Racer)
:cool:
Nice numbers, what about the lower lifts ?
At what water gauge did you get the numbers ?
any pictures ?
i never did flow mine so it would be nice to see what you did as a compearson
:cheers:
Nice numbers, what about the lower lifts ?
At what water gauge did you get the numbers ?
any pictures ?
i never did flow mine so it would be nice to see what you did as a compearson
:cheers:
Melting Slicks
Joined: Apr 2000
Posts: 3,490
Likes: 2
From: Oviedo FL
Re: Ported heads complete (BLUE ONE)
He has a flow bench at the School. He also has the numbers for the lower lifts and will post them later. Right now he's on his way to my house to help me with my battery problems.
We're going to the track tonight, so he should have some new numbers to post. I believe the Supra boys are in town this weekend and they will all be at the track tonight, along with Limey and GTB/ZR1. It should be a fun evening...
Mike
We're going to the track tonight, so he should have some new numbers to post. I believe the Supra boys are in town this weekend and they will all be at the track tonight, along with Limey and GTB/ZR1. It should be a fun evening...
Mike
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: Ported heads complete (Aaron's 87)
bout the same i got when i did mine except the exhaust, i'm floored the pre 88 non D port head is that far behind in exhaust flow. i got a best of 225cfm@.500/intake after my porting on std valves. i never did flow again after we undercut them but i'm sure i picked up a cfm or two. my exhaust went all the way up to 185cfm@.500 though !! there's one hell of a difference in the two castings i guess. here's a link to my flow chart by the way, this is also the first set of heads i ever did :jester http://forums.corvetteforum.com/zerothread?id=379838
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Ported heads complete (gtsyellow)
I do have a flowbench at school here that I use (it's at the University of Central Florida....Master's degree in racing engine optimization)
All flow numbers that I have are at 28" of H2O - standard number, though it must be converted to 20.54" to be of any design use.
This was also my first set of heads, but I do want to emphasize one thing here on the flow numbers....all I did was a bowl blend, port match and valve work. I did not go in with the intention of hogging out the heads, as I do not currently have the cam or intake to support that kind of flow. There is a LOT more material in there that I can remove.
FWIW, the car's previous best 1/4 was 14.9 @ 92. Tonight at Bithlo (Orlando SpeedWorld) I ran a 14.2 @ 100 blowing the tires off the car for the first 60' (I was running on 315 Hoosiers and thought the track would hold a harder launch....it didn't) The only things that have been done to the car since it's previous best is the ZF swap (which slowed the car down on accel because I still have 3.07's in it) and the head work.
All flow numbers that I have are at 28" of H2O - standard number, though it must be converted to 20.54" to be of any design use.
This was also my first set of heads, but I do want to emphasize one thing here on the flow numbers....all I did was a bowl blend, port match and valve work. I did not go in with the intention of hogging out the heads, as I do not currently have the cam or intake to support that kind of flow. There is a LOT more material in there that I can remove.
FWIW, the car's previous best 1/4 was 14.9 @ 92. Tonight at Bithlo (Orlando SpeedWorld) I ran a 14.2 @ 100 blowing the tires off the car for the first 60' (I was running on 315 Hoosiers and thought the track would hold a harder launch....it didn't) The only things that have been done to the car since it's previous best is the ZF swap (which slowed the car down on accel because I still have 3.07's in it) and the head work.
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Ported heads complete (ski_dwn_it)
Also, FWIW, I do have the lower flow numbers, at 0.100", 0.200", 0.300", 0.400" and 0.500", unfortunately they're sitting in my backpack in Luvmy92's garage with all the rest of the crap that was in my tire trailer....and the trailer itself....sorry about that Mike!
The flowbench that I used is a SuperFlow 600F.
The flowbench that I used is a SuperFlow 600F.
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Ported heads complete (CorvetteZ51Racer)
Wow, you know you're out of it when you reply 3 times in a row to your own friggin thread!!!
Anyway, I do have pictures of the head work....some before, during, after, on flowbench, and during reinstallation that I can post, but I don't know when I can get them up. The digital cam is broken so I have to develop and scan these things, and I'm going out of town for a week starting monday morning....I will get them up ASAP however.
Anyway, I do have pictures of the head work....some before, during, after, on flowbench, and during reinstallation that I can post, but I don't know when I can get them up. The digital cam is broken so I have to develop and scan these things, and I'm going out of town for a week starting monday morning....I will get them up ASAP however.
Pro
Joined: Mar 2001
Posts: 602
Likes: 1
From: Hacienda Heights, Ca. USA
Re: Ported heads complete (CorvetteZ51Racer)
I posted the flow numbers on my CNC ported L-98 alum heads several months ago. I had 225 cfm @ .550 lift on the intake, and 194 cfm on the exhaust at .550 lift, and that was before the 3 angle valve job! That was with the stock sized valves and before the valve job. Not bad for a set of factory heads huh? :cheers: