Hey FI group! Quick question and hoping to find a few quick replies (looking at buying some new heads). If I were to buy a 243 head (64cc stock) that is milled .040 and ran this on about 14 lbs of boost, would I be able to prevent the heads from lifting or would the deck be too thin? Thanks.


edit: forgot to mention, the engine will stay N/A for probably 8-12 months, at least

 

well, I just found this...
https://ls1tech.com/forums/forced-in...lbs-boost.html

but still open for opinions 3 years later...

 

I am about 9.9:1 CR but with a non milled 243 head. IF you don't go crazy milling them I think you should be fine and not push water

 

off subject, schmitte, didnt you do your own porting??

 

yes I did. I had a machine shop cut in the larger exhaust valve and I cleaned them up. Nothing major just hit all the important parts

 

yeah. I got to reading that thread I posted above and I'm starting to think a head milled .040 is too much, unless I swap heads when the procharger build comes around. catch is these ported 243 heads I'm looking at buying are only $300 more than what I'll be putting into stock 243's without being ported.

 

lol, thanks man, sorry OP, end of thread jack

 

How much would you be buying them for. Need to remember that you will need different push rods also for a milled head that might not be able to be reused later. What would your CR be with a stock unmilled 243

 

about $900. complete with dual springs, upgraded retainers, & all. I already have a set of dual springs however I have to buy a tool or pay someone to swap them over to a non-ported 243, plus the idea of getting the stock 243 milled just a bit (cleanup purposes & a little more cr). With an unmilled 243 my scr will be pretty close to 9.2. I know with the ported 243 I'd gain about 15-20rwhp over the non-ported 243, but with these heads I'd also gain another .47 in compression, which would help power obviously.

 

Well I have about $800 in my 243 heads that includes the sodium filled intake valves, larger exhaust valves, machine work, springs and porting. IF I where you try and find a ported 5.3 head that will raise your compression and isn't milled.

If you motor is forged you really shouldn't have any issues running 10:1 CR and boost

 

I think you'd be fine at 14 psi. Bob