Did you guys forget his original post?

The L98 heads are just that, they are not a great head by any means but better than what is on there now. If the goal is more than 400 hp in the long run then do not buy them, under 400 hp they are not a bad option but not the only one either.

 

Its not. People do it all the time. There is not that much you can do anyway other than replace bearings and rings. I'm really sorry that i ever rebuilt my bottom end. It didn't conusme oil before but did after the rebuild. The machine shop got the bores too sloppy. I'm not convinced forged pistons can be fitted to the bore to not consume oil. As long as your not coonsuming oil i say leave it alone. Most C3ers only put a few thousand miles a year on their rides anyway. No need for a new rebuild.

 

I too believed it was not a good thing to put new heads on an old bottom end. So I posed the question to Lars. Here's what he said:

"No reason to rebuild a SBC with only 100K on it. The only 2 things that wear out at 100K are the timing chain and the valve guides, and at 65K the chain isn't even shot. Slap the AFRs on it and have some fun. Rebuild it at 250K."

 

the reason I want to do heads is to free up some hp but also the right side needs valve guides because it smokes.

 

I have 2 L98 TPI motors in vehicles and am very happy, but by the time you buy used L98 heads and have them rebuilt you will be in the same ballpark moneywise as new Vortecs. The Vortecs flow much better out of the box than ported L98s. Just bite the bullet and buy new Vortecs in a kit and be done with it. My .02.

If I had not found a deal on a complete low-mile L98 for my truck, I would have built a TPI with Vortecs, you can get a Vortec TPI intake now. Good luck with your car.

 

the test in Chev Hi Performance determined that they were equivalent.

I like the L98s for their light weight and their screw in studs and guideplates which will accomodate higher lifts and 1.6 ratio rockers.

 

I must not be reading things correctly. The stock Vortec out performed all others in that group. Some of the aluminum heads were in the ball park and would be a toss up, but the L98 heads were not one of them.

lift L98 Vortec
.300 160 190
.400 186 227
.500 196 239

One of the best things about the Chev Hi Performance article is that they tested a lot of the popular heads. The results are comparable. It would be impossible to compare flow results from one company versus another since they may be using different test equipment. If your looking for great heads and to save weight, then neither of the heads would be the wisest choice. For someone who has a stock L48 and not a lot of money the Vortecs make a lot of sense. You do have to buy a Vortec style intake and center-bolt valve covers but you would have to buy an intake if you purchased conventional type of aftermarket heads. There would be little sense to leave the old cast intake and orange painted valve covers on the car. The biggest decesion that has to be made is in regards to the maximum lift the stock heads can accomadate which is .480". For $160 a set of Crane springs and retainers can be installed to get a maximum lift of .550" with little to no machining. The issue with the kit is that it adds to the price and takes away some of the advantage of these heads. The advantage I'm referring to is good flow versus the cost.