Upgrading heads 195cc to 220cc's.
Thread Starter
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
Upgrading heads 195cc to 220cc's.
The 421 is due for an upgrade. This will be the final upgrade in regards to the engine (stop laughing *****).
I have decided to sell my 195 cc AFR comp ports, and buy some 220 cc AFR comp ports.
The 195's did very well considering they poured in at 196cc, but the port was a tad small for the cubes. The heads flowed an honest 303 cfm which was incredible.
So time will tell but the heads will be put on in the spring sometime, and I am curious as to what gains will be had.
The old combo dynoed 434 rwhp 471 rwtq with the ****** B&B reasonator which certainly doesnt help hp but it does quiet the exhaust note.
I am of the opinion with the reasonator removed, and the x pipe installed and a little more tuning 450rwhp 480 rwtq wasnt out of the question.
Miniram too!
The question is......What gains with the bigger ports?
(B&B's. Not Borla)
I have decided to sell my 195 cc AFR comp ports, and buy some 220 cc AFR comp ports.
The 195's did very well considering they poured in at 196cc, but the port was a tad small for the cubes. The heads flowed an honest 303 cfm which was incredible.
So time will tell but the heads will be put on in the spring sometime, and I am curious as to what gains will be had.
The old combo dynoed 434 rwhp 471 rwtq with the ****** B&B reasonator which certainly doesnt help hp but it does quiet the exhaust note.
I am of the opinion with the reasonator removed, and the x pipe installed and a little more tuning 450rwhp 480 rwtq wasnt out of the question.
Miniram too!
The question is......What gains with the bigger ports?
(B&B's. Not Borla)
Last edited by 88BlackZ-51; Feb 2, 2013 at 01:03 AM.
Thread Starter
Race Director
Joined: May 2003
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I am going with 3.45's so this is my thinking as well.....Heads cushion the bottom a bit with some extra legs up top.
Racer
Joined: Sep 2007
Posts: 493
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From: Eden Utah
You really do want to go fast. Which heads did Jim put on his engine...
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
If you're going to go to a 3.45 rear ratio, you need to get a dyno test with the 195's and then change the heads if you want to see what the true power increase is. 3.45's will show some higher power results over the 3.07's without any change to anything else.
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I think the power gains will be well worth the effort. I would think you will pick up at least 25hp.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Driving it like he hated it as is with 3.45s to 6500 and not shifting it like aunt flo oughta leave him satisified.
It should pick up some Rick forget the dyno the resonator and all that just get to the track and drive that thing.
It should pick up some Rick forget the dyno the resonator and all that just get to the track and drive that thing.
Race Director
Joined: Sep 2001
Posts: 14,686
Likes: 753
From: NEwhere Ohio
amen to this.
Are you getting heads a little bigger cc so you will have a CR thats blower-friendly?
BTW. I dont believe you need lousy 9.0:1 compression ratio for a centrifugal blower spraying methanol to cool the intake.
I think the optimum CR for an 18 psi blower is more like 10.0:1.
Modern technology (methanol injection) has changed the game again when it comes to compression ratios and blowers.
Crap the LSx guys run 10.5, 11.0:1 and pour 18 psi boost thru their combos to make insane power.
Are you getting heads a little bigger cc so you will have a CR thats blower-friendly?
BTW. I dont believe you need lousy 9.0:1 compression ratio for a centrifugal blower spraying methanol to cool the intake.
I think the optimum CR for an 18 psi blower is more like 10.0:1.
Modern technology (methanol injection) has changed the game again when it comes to compression ratios and blowers.
Crap the LSx guys run 10.5, 11.0:1 and pour 18 psi boost thru their combos to make insane power.
Instructor
Joined: Dec 2004
Posts: 135
Likes: 0
From: Pickering Ontario
Hi Rick
I think you will see a big bump in power. I found when I went to the 220 heads and full 3 inch duals, with hi flow cats the engine woke up big time.
You might want some shaft rockers to go with the heads just to keep things stable.
Good luck and have fun.
Brian
I think you will see a big bump in power. I found when I went to the 220 heads and full 3 inch duals, with hi flow cats the engine woke up big time.
You might want some shaft rockers to go with the heads just to keep things stable.
Good luck and have fun.
Brian
Le Mans Master
Joined: May 2004
Posts: 5,389
Likes: 534
From the builder himself. The torque numbers are very impressive of this build, personally. A motor with V10 torque that can sweep past 6,000 rpm. The heads won't be the last stop..... Jim likes his spray, wouldn't be surprised if he put that bug in your ear. Makes his car look sped up on footage when he hits it.
Melting Slicks
Joined: Jul 2003
Posts: 2,284
Likes: 4
From: Canton MI
Hey Rick,
Why not go with the 235 ?? They only have a MCSA of 2.47 at the pinch with plenty of velocity to work fine on the street, dont get all caught up with the CC #s . You have a 421 CI with good amount of CR, why choke it with a small head ?
Why not go with the 235 ?? They only have a MCSA of 2.47 at the pinch with plenty of velocity to work fine on the street, dont get all caught up with the CC #s . You have a 421 CI with good amount of CR, why choke it with a small head ?
Last edited by red L98; Feb 3, 2013 at 12:59 PM.
Thread Starter
Race Director
Joined: May 2003
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The car is a street car with the odd trip to a rd course plus the 220's accept the rockers I have....I understand what you are saying but we think the 220's will let if breath a bit more...We are also going to change up the compression a tad meaning lowering it just a bit. Its getting harder for me to find 94.
Last edited by 88BlackZ-51; Feb 3, 2013 at 07:56 AM.
Thread Starter
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
From the builder himself. The torque numbers are very impressive of this build, personally. A motor with V10 torque that can sweep past 6,000 rpm. The heads won't be the last stop..... Jim likes his spray, wouldn't be surprised if he put that bug in your ear. Makes his car look sped up on footage when he hits it.
Thread Starter
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
Yes I think the mid range and top end revs will increase. I remember seeing your dyno curve from a few years back and being impressed. Did you sell your C4?