westmma385

About to install tsp headers, tsp 228/232 600/600 114 lsa cam, high flow cats and corsa sport exhaust.

Have a set of 243 heads and wanted to know how much $$$ and how much hp would i expect if i port and polish?

tuner estimated 415 rwhp for above (stock 243 heads) and wanted to know how much would i gain if i send heads to get port/polished. Also any recommendations as im in Houston and saw TSP does it for $750.

silver408z

750 seems cheap, most places I have seen do it charge like 1250. I have no experience with any of these shops but other options are Frankenstein Enginee Dynamics, Total Engine Airflow (Tea) and advance Inductions (AI).

0FrankensteinE.D.

westmma385,


I can't beat $750. For $1150 you'll have new .660" spring kit with Ti retainers. CNC port, CNC valve job, Laser logo, hand blend, surface, final wash and assembly.


-Russ

01badvette

With stock 243's 400-415rwhp is possible with those mods, I quality p&p with valve job may gain you another 15-25rwhp. $750 is cheap if TSP will do it for that price, I have the TSP LS6 2.5 heads and have been very happy with them.

tombrammer

Will you do the header install yourself? If so be sure and post back here on how the install goes, I would like to get a set of these if the install is "easy". Thanks

01badvette

I've had my TSP LT headers on and off the car a few different times now and it goes quite easily. Disconnect the steering shaft, take off the valve covers, starter and oil filter and both header will drop in from the top without issue.

blue02ZO6

How long does this take once you have the heads?

FASTFATBOY

Heads haven't been ""polished" since the 80's, stop going to car shows.

Call Advanced Induction.

If you want a cheap exceptional port job contact Killian's porting service in Ga. He only does port work, thats it.

Antz97znj

Went with the AI HCR 241 program, very happy w/ the results here. From what im told the numbers are very close to 243's.

SLVRVERT

I have been reading some things on the 241 to 243 cylinder head swap. Just wandering if the 243s would bolt right up considering I have 241s on there now. Also what would be the gains to changing the heads and what would be needed to complete the job? Any help will be much appreciated. Thank you in advance.

ChrisLSx

I'm trying to decide whether or not it's worth the $600 (+ shipping) to have Texas Speed CNC port the pair of 243 heads I have. My goal is ~400rwhp and I'm going with a fairly mild cam (something like a 214/218 on a 116). I'm currently inclined to just keep the factory valves, have the seats/valve angles cleaned up and hand polish out any casting flash.

Thoughts/input?

ASRoff

yes the 243/799 heads are the best flowing cathedral heads Gem produced.... they were so good, GM used them on the Ls2 as well. they will certainly outflow 241's AI is who I would go with to get them done... Kurt Urban himself recommended them and if Kurt says they are good... Well.....

If you get CNC ported 243's you will be above 400whp even with a mild cam....

FASTFATBOY

With stock 243's that have a good valve job, LS6 intake and a mild cam you'll make over 400rwhp with a stick....easliy. This setup makes 385rwhp with headers,intake and tune on a LS6 regularly.

Millenium Z06

A better question would be "do you have any proven results"?

bigmackloud

I just installed the TSP/PRC stage 1 cnc ported 243's (actually they were 799's, but they're the same). They are a very nice looking head. I also had them milled around .025" to put me at 60cc, which should put my combo around 11:1. (JE pistons, Eagle H beam rods, GM MLS head gasket) And I'm running a Titan 4 cam. Previously I had stock 241 heads and a TR220 cam, which made 370 rwhp.

While the motor is mostly together, I've still got a fair amount of work to do getting the motor back in the car, etc. But definitely looking forward to getting it on the dyno. I'm hoping for 420-430 rwhp.

Roddy13

I'm going with the Frankenstien heads myself.

FASTFATBOY

If your piston has a 4 cc relief 60cc head won't put you at 11 to 1. You need to measure where the piston is in the hole and do the math.

I had to get to 58CC to make 11 to 1 on mine with a GM MLS gasket

Millenium Z06

research

sstonebreaker

I had an England Green Mayhem 2 cam and bone stock 241 heads on my '04 manual. It made 408 rwhp on the dyno. I ran it for three years without freshening the valve springs and paid big time - two of my lifters started bouncing off the cam lobes and eventually shattered and lunched the engine.

During the rebuild, I had AI do my 241 heads. In addition to the port work, they welded up and reshaped the combustion chambers to 58 cc, which I believe will bump my compression ratio to 11.5. AI estimates that along with the 234/242/112 cam, I should see around 460 rwhp.

Since I also burned the clutch, I decided to replace it with the C5 LS7 kit that Scoggin Dickey offers. It's a little heavy and may bring down my peak hp a little, but the OEM reliability is a good tradeoff for a few peak hp.

I should be getting it dynoed here in the next couple of weeks.

tnmotown

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