98lswonz28

Update... I have the head at the head shop getting an oversized guide put in... I have a question on ptv clearance... the car has wiseco flat top pistons and thumped cam that will get swapped for either an ms4 or trex cam...the heads are gtp stage 3 243 heads that I believe ate slightly milled. They have 2.1 intake valves and not sure on the exhaust... I was wondering if I would have ptv issues with a ms4 or trex cam with these heads... I also just got a set of 862 5.3 heads I was wondering the same on those and how much more of a gain would I get out of the gtp heads over the 5.3 heads... this motor will also see a 150 shot ... thanks for the help

SOMSS

iTrader: (1)

TREX cam was designed for stock heads. Don't think it will work as well with PP/HC car.

96lt4c4

iTrader: (5)

How can the guide be completly gone? If it came loose it would have to be in there somwhere.

98lswonz28

From the scratches it looks like the valve banged it a little and hopefully it got spit out of the exhaust and not stuck in the piston... I'm sure the trex would have no problem making over 450hp with these heads..just wondering if ptv is an issue

SS4Luck

iTrader: (10)

most trex's ive seen make over 450 on stock 243s let alone a head with work done

LS1-450

iTrader: (33)

It's possible that a hanging injector caused it, but may never know for sure. Regardless, I'd replace the head itself. Losing a valve guide isn't typical & once it happens, may end up to be a re-occurring condition. 241's can be found for very little money in the for sale section. Get a set & do some home porting. She'll be good to go.

98lswonz28

I guess now would be a good time to ask about what gaskets...I have heard cometic? Also would it be wise to go with studs? And when to go with roller rockers

BahN

iTrader: (9)

I second new heads. For the money, you can't beat the reassurance. As for head gaskets, i love MLS (personal opinion)

Darkman

iTrader: (2)

If you are doing the head swap yourself the MLS gasket is more forgiving in terms of how clean the block needs to be. I would stick with the OEM TTY head bolts (new, of course) as well as the OEM rockers. You might consider a trunion upgrade for the rockers, but that is entirely optional.

BlackScreaminMachine

iTrader: (17)

When you start running 500-550 RWHP stock blocks start to have issues. Some last a while some not as much. Your at the "redline". Just be aware. Having better fasteners, as well as rods/pistons will certainly help but I would say if your making 425/450 on cam and injecting 100-125 shot with appropriate tune, plugs, fuel, and Nitrous Safety stuff, you should be fine.

I would not push it more.

Also since the head needs to be fixed, Magnaflux the Piston which CAN be bought as a DIY kit. Eastwood had them, just do a google search on it.

Here is the kit....

http://www.amazon.com/Magnaflux-SK-4.../dp/B000LB6ACA

98lswonz28

Thanks for the help guys... hopefully this thing holds together for a while... I remember seeing guys with stock ls1s running trex cam and 200 shot with no probs years ago so hopefully being fully forged with 4340 crank will handle it...

98lswonz28

Edited check first post