L$X$10

iTrader: (4)

I'm in the process of doing a budget LS1 swap(pulling the 5.3) and have a set of 243's I'm going to use. I would love to have the heads fully worked for the max potential gain, but funds won't allow for that. From my understanding the majority of gain you see from the head work is in the valve job anyway. If this is the case I figure I need to make sure this is performed, and performed RIGHT. I have a guy here locally that does amazing work but my concern is that he isn't familiar with LS heads. Is there a good DIY thread or video I can provide him with so that the method he follows is specific to the LS(243) head? If not(option 2) who is my best bet to send my heads off to for a great LS specific valve job?

xRaTeD

3 angle top cut 75 in the bowl 90 plunge to 88 percent of the valve diameter and then blend by hand into bowl.. I have been using a radius cutter on the exhaust..

KCS

iTrader: (20)

If he is good with Ford heads, he should be good with LSx heads. They're very similar as far as the layout of the port and valvetrain setup. It's not just the method, but also the cutter profile that will determine the gains in power output, but those profiles are typically held close to the chest. If you dig around the Internet, you may find some part numbers that work really well. Try Speedtalk for starters.

Once you have the valvejob cut, it's also important to have the throat sized accordingly and to blend in the angles. Opening the throat to 90-92% of the valve diameter is common with ported heads, and can be done when the valvejob is being cut, if he has the tooling for it.

I did this on my 241 heads that are in my car now. I cut the valvejob in an afternoon and blended it all in with a grinder in my garage during commercial breaks one night. I didn't spend a lot of time on it making it pretty or anything, just quick and dirty.

xRaTeD

xRaTeD

92 percent is too much IMO and is backed up but most
Really good cnc heads I have tested....

Small ports big valves and throats don'T
Work to well there is a good thread on yellow. Bullet provided by kcs.

L$X$10

iTrader: (4)

Thanks for the reply's...keep them coming!

KCS, Ford heads are his specialty.

Rise of the Phoenix

iTrader: (27)

If money is tight, you could always sell the 243 heads and have Advanced Induction work over the 241 heads with their High Compression 219cc program (assuming you still have them). $995.00 for machining and labor costs. I bet you could get $400+ for the 243 heads.

https://ls1tech.com/forums/dynamomet...o-results.html

KCS

iTrader: (20)

I agree about 92%, I'm not a big fan of that but I've seen it on some popular CNC heads and they really weren't that impressive. I put mine at 90% except for my super secret squirrel 243 heads with those big valves.