Porting 243 heads
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
Porting 243 heads
Hey guys,
I am thinking about yanking my stock heads off and having them opened up. I am staying NA, and the fast intake and ported heads will be my last mods HP mods. I don't want to spend 2200+install on AFR's, and I know some guys have run great times with 243 heads. My car is going in tomorrow for an England Green Mayhem cam. (high 23X/low 24x).
What exactly needs to be done to the 243 head for an NA 5.7?
Mark
I am thinking about yanking my stock heads off and having them opened up. I am staying NA, and the fast intake and ported heads will be my last mods HP mods. I don't want to spend 2200+install on AFR's, and I know some guys have run great times with 243 heads. My car is going in tomorrow for an England Green Mayhem cam. (high 23X/low 24x).
What exactly needs to be done to the 243 head for an NA 5.7?
Mark
Melting Slicks
Joined: Sep 2003
Posts: 2,458
Likes: 105
From: Northville Michigan
Patriot Performance does a good job with 243 heads, and their price is reasonable. Be sure you have them fit valve springs that work with your camshaft:
http://<a href="https://www.patriot-...=37&page=1</a>
.
http://<a href="https://www.patriot-...=37&page=1</a>
.
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
Yeah, I am really trying to stay away from them. I have a guy locally that will sale me his for 800 and they are brand new. However, I've heard that they really don't make much power over the stock 243 heads NA. My tuner actually gained nothing with them over the stock 243 heads on 2 cars(5.7). I'm really looking at a good hand port job, but need some advice as to exactly what needs to be done on them.
Banned Scam/Spammer
Joined: May 2007
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From: Machineguns, because I don’t compromise
Quality hand porting costs money because of the time involved. CNC is much better for even results over 8 cylinders. IMO
I heard (it's been over a year now) that Texas Speed will cnc your castings for around $600. I'm not sure if that covered a valve job.
My stock 243's were pretty cruddy with 68k miles even with a catch can and Seafoam.
I heard (it's been over a year now) that Texas Speed will cnc your castings for around $600. I'm not sure if that covered a valve job.
My stock 243's were pretty cruddy with 68k miles even with a catch can and Seafoam.
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
Quality hand porting costs money because of the time involved. CNC is much better for even results over 8 cylinders. IMO
I heard (it's been over a year now) that Texas Speed will cnc your castings for around $600. I'm not sure if that covered a valve job.
My stock 243's were pretty cruddy with 68k miles even with a catch can and Seafoam.
I heard (it's been over a year now) that Texas Speed will cnc your castings for around $600. I'm not sure if that covered a valve job.
My stock 243's were pretty cruddy with 68k miles even with a catch can and Seafoam.
Safety Car
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From: You know your drunk when you swerve to miss the tree then you realize its your air freshener! Covington Ga
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
Safety Car
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From: You know your drunk when you swerve to miss the tree then you realize its your air freshener! Covington Ga
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Safety Car
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From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
Yeah, I am really trying to stay away from them. I have a guy locally that will sale me his for 800 and they are brand new. However, I've heard that they really don't make much power over the stock 243 heads NA. My tuner actually gained nothing with them over the stock 243 heads on 2 cars(5.7). I'm really looking at a good hand port job, but need some advice as to exactly what needs to be done on them.
Melting Slicks
Joined: Dec 2006
Posts: 2,186
Likes: 2
From: Woodinville WA
TEA is really good, and have a great reputation. If I were to get another set of heads done I'd contact them.
I agree that some ported 243 heads are crap, my Livernois ported heads sucked dog turds for my application.
Of course a lot of maximizing a combo is getting parts that work well together so it is probably best to have the company who is supplying the heads to choose your cam profile for you. Because they will choose a grind that works best with the flow characteristics of thier heads.
I agree that some ported 243 heads are crap, my Livernois ported heads sucked dog turds for my application.
Of course a lot of maximizing a combo is getting parts that work well together so it is probably best to have the company who is supplying the heads to choose your cam profile for you. Because they will choose a grind that works best with the flow characteristics of thier heads.
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
No problem.
Of course a lot of maximizing a combo is getting parts that work well together so it is probably best to have the company who is supplying the heads to choose your cam profile for you. Because they will choose a grind that works best with the flow characteristics of thier heads.
Race Director
Joined: Dec 2006
Posts: 12,356
Likes: 2,893
From: Fort Worth, Texas
TEA is who I was gonna suggest if you're wanting to get the most out of your 243s. I would recommend having them milled to 59cc if it can be done with out flycutting. With that big cam you want as much compression as possible, although milling hurts flow numbers slighty. You will probably gain 30rwhp imo and should then be able to run a 10 even without skinnies
what injectors are you gonna run Mark?
what injectors are you gonna run Mark?
Last edited by PRE-Z06; May 14, 2010 at 03:36 AM.
Thread Starter
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
Chris, you know I am up in the air. I really have not looked up the duty cycle of injectors since I was in high school, so I have no idea. My cutouts were installed today. Hopefully, I can gain 5-10hp from them.
Looking for suggestions from people like yourself. My car goes in tomorrow to EG. Jason at EG is making some calls about the 243's to some guys. We have some nice head porting shops in Houston, and I'm going to see what they say. I'll weight this vs. just going with a ported 90-92 Fast.
I posted on the Texas Section on LS1 tech, and most people PM'd me about TEA, so that they would not upset their local tuners. They have a wide range of porting, so I figure it is woth a chat with them and let them suggest a head for my cam spec.
Looking for suggestions from people like yourself. My car goes in tomorrow to EG. Jason at EG is making some calls about the 243's to some guys. We have some nice head porting shops in Houston, and I'm going to see what they say. I'll weight this vs. just going with a ported 90-92 Fast.
I posted on the Texas Section on LS1 tech, and most people PM'd me about TEA, so that they would not upset their local tuners. They have a wide range of porting, so I figure it is woth a chat with them and let them suggest a head for my cam spec.
Last edited by winters97gt; May 14, 2010 at 03:57 AM.
Race Director
Joined: Dec 2006
Posts: 12,356
Likes: 2,893
From: Fort Worth, Texas
With the cam alone I am willing to bet your injectors are maxed even in this weather, the better the DA the more they will be taxed...the intake is ultimately limited by the heads as far as airflow goes, but 2 of my buddies who just swapped from ls6 to Fast both gained ~15/10 with 228/232 114 cams...assuming you're only doing one or the other for now, heads vs. intake will cost close to the same and I would lean more towards the heads going with a big cam that will drop DCR, plus you need new valve springs anyways making it the perfect time to install them and believe you will see more of a gain since you'll be taking more advantage of the cams big lift too. If you then decide to do the FAST later down the rode, it will make it's gain that much bigger. What CAI do you run again?
Last edited by PRE-Z06; May 14, 2010 at 05:47 AM.
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
Just Porting is not always a good idea. but having proeprly ported heads to your application is.
I took a new set of GM 243 heads to a friend, and we cleaned up or polished the rough edges inside. not really porting to make the runners larger Then he milled the heads down to approx 60.5cc
Installed Ti intake and Sodum filled exhaust valves, Ti retainers and Comp 918 springs.
then he had them flow benched. The polishing did pic up a few cubic mm of air velocity at .200 to .550 of lift over stock numbers. Not quite what a good porter my get.
I run a small cam 224/224 .581/.581 112+4
typical other bolt ons, LTs, high flow cats, straight pipes. TPIS pp 78mmtb, my own CAI. 3qt accu-sump and oil cooler.
Numbers are still in the low 400s to the ground for hp and tq. and 20,000 miles of 3,000 to 6750 rpm ( track car) and pulling the heads each winter with checking valves and replaces the springs, injectors, plugs and wires each winter. So I am happy for now.
I took a new set of GM 243 heads to a friend, and we cleaned up or polished the rough edges inside. not really porting to make the runners larger Then he milled the heads down to approx 60.5cc
Installed Ti intake and Sodum filled exhaust valves, Ti retainers and Comp 918 springs.
then he had them flow benched. The polishing did pic up a few cubic mm of air velocity at .200 to .550 of lift over stock numbers. Not quite what a good porter my get.
I run a small cam 224/224 .581/.581 112+4
typical other bolt ons, LTs, high flow cats, straight pipes. TPIS pp 78mmtb, my own CAI. 3qt accu-sump and oil cooler.
Numbers are still in the low 400s to the ground for hp and tq. and 20,000 miles of 3,000 to 6750 rpm ( track car) and pulling the heads each winter with checking valves and replaces the springs, injectors, plugs and wires each winter. So I am happy for now.
