574's TVS mini build
I'm lazy today, so here.. lol
https://www.cobaltss.net/forums/memb...0438883-15062/
https://www.cobaltss.net/forums/memb...0438883-15062/
you need to have your valves spun and check for out of center. I had mine done and even on an unmodified head they were bent. 
I am running a 3 angle valve job with ferrea valves and a mild ported head with 82# zzp valve springs. My moderate street CNC port job picked me us some power no doubt. Cant wait to see if you surpass all these other dyno runs with those monster port jobs.
I am running a 3 angle valve job with ferrea valves and a mild ported head with 82# zzp valve springs. My moderate street CNC port job picked me us some power no doubt. Cant wait to see if you surpass all these other dyno runs with those monster port jobs.
you need to have your valves spun and check for out of center. I had mine done and even on an unmodified head they were bent.
I am running a 3 angle valve job with ferrea valves and a mild ported head with 82# zzp valve springs. My moderate street CNC port job picked me us some power no doubt. Cant wait to see if you surpass all these other dyno runs with those monster port jobs.
I am running a 3 angle valve job with ferrea valves and a mild ported head with 82# zzp valve springs. My moderate street CNC port job picked me us some power no doubt. Cant wait to see if you surpass all these other dyno runs with those monster port jobs.
Senior Member
Joined: 12-31-06
Posts: 686
Likes: 4
From: troy oh
They're 1.65'" across
btw, a tvs car will benefit from a larger port, where as a turbo car likes the velocity of a smaller port.
I'm speaking generally on that.
regardless a ported head WILL help most engines.
This is one reason the saab version (b20wtfbbq) used the smaller ex ports
btw, a tvs car will benefit from a larger port, where as a turbo car likes the velocity of a smaller port.
I'm speaking generally on that.
regardless a ported head WILL help most engines.
This is one reason the saab version (b20wtfbbq) used the smaller ex ports
Last edited by lsjion; Mar 1, 2013 at 03:02 PM.
Joined: 05-18-11
Posts: 39,564
Likes: 87
From: West Chicago, IL
i think i heard something like a sc car likes the exhaust ports to be 3/4 the size of the intakes or something like that
there was a really good discussion of that in the tvs thread, but i wouldn't dare try to find it
there was a really good discussion of that in the tvs thread, but i wouldn't dare try to find it
Last edited by riceburner; Mar 1, 2013 at 03:17 PM. Reason: Automerged Doublepost
too bad I'm in Indy all weekend
I didnt have the exhaust ported, I felt like was posted above, that the turbo would be better suited for exhaust left alone, intake was 1 or 2 mm larger than stock. CNC'd but it was the area around the valves that really opened up.
1.526 inches, had to convert it. that .4 inches bigger ports, equal to almost a half inch bigger on your end. NICE
1.526 inches, had to convert it. that .4 inches bigger ports, equal to almost a half inch bigger on your end. NICE
Last edited by c130aviator; Mar 2, 2013 at 01:13 PM.
Here ye here ye. Got my head today and did some dirty things. Next weekend its on like donky kong. If everything goes as planned it will be running by monday. No WOT because of new clutch and I'll be running the tune that I had for my 2.9 with the new 2.6
Before and after picture. Same screw from TVS pulley
lsjion does great work 
Before and after picture. Same screw from TVS pulley
lsjion does great work