Okay so iv'e got this lt1 that has about 90,000 miles on it. Iv'e got the heads off for porting but could use some advice.

The cylinder walls look excellent imo there is still crosshatching and just a little carbon on the tops.
The question is does it really need to be messed with i feel like it would do more harm than good to rering and put arp hardware in the bottom end unless i was to do bearings.

The plan was to just port the heads and throw the lifters and cam in it but its apart... What should i do?
I dont trust any of the local machine shops and know just enough to be dangerous when it comes to bearings and rebuilding engines.
But its about time i tried. Is there a rebuild kit that comes with stock sized bearings and stock sized forged pistons?

 

i was thinking this? Sealed Power CSMHP766-000 - Federal Mogul Premium Engine Rebuild Kits - Overview - SummitRacing.com

 

So I guess the pistons in that kit are too heavy, I dont think im going to touch the bottom end it looks fine.

 

my engine builder used a set like that only mine is .03 over and not forged and it hasnt flew apart yet although im just spinning to stock redline (every chance i get haha). roughly 6000 miles

but as you said the cross-hatching was still in the walls so i'd imagine it would be just fine. If it was me i would put new bearings and arp hardware in it just for that extra piece of mind when your beating on it.

as far as you putting it together, if you trust yourself to do the work and you have the right tools then you should be good to go. just ask questions and take your time. im kicking myself for not building my own engine.

 

What do you think of these. They need some more but its where im at...

 

Some guys go to 7000 on untouched stock bottomends without issue, most seem to prefer to keep the stock parts below 6500rpm just to keep life a little easier on the stock rod bearings/bolts.

How high are you looking to turn it when done?

 

Well i think my rev limiter is at 6500 in the pcmforless tune but its for sure 6800 or less. Ive taken it there several times. Always up to proper operating temp for awhile and it always has 10w30 mobile one synthetic. It never blew then so why would it be any different with lt4 cam and ported heads? Does anyone have any opinions on my crappy head cleanup job lol?
basically ive got to be able to make more power with just cleaning these things. Theres like a cm of soot caked on everywhere

 

You might do some actual meaningful research on oils instead of relying on pure marketing.
Bob Is The Oil Guy - Forums powered by UBB.threads™

I haven't looked into it in some time but M1 10w-30 was always the thinnest of their 30weight oils(5w-30 and 10w-30 were thicker) and M1 had always resulted in high iron wear metal content in used oil. Not catastrophically high but high enough to make someone reconsider what they were paying when something cheaper could often deliver a better result.

Far as the rpms needed you are not clear was the car previously stock? I would have a hard time believing you were pushing a stock cam to 6500rpm. A cam upgrade will pretty much always require more rpm to make use of and even if using the same cam porting the heads will likely allow the cam to make more power to a higher rpm. So you statement.

Really begs the question. Do you have the foggiest clue?

Far as the porting if only porting half the runner the bowl is vastly more important, opening it up by the intake flange and not working the bowl is not a good thing to do. Lots of posts on how a gasket match style porting job is wrong.
If trying to do budget head work money is best spent in the bowls but this is also where a novice can do the most harm if you foul up the short side.

 

what are you matching the ports too? air slows down wen it changes direction like hitting into a 90* angle from the intake to the edge of the port/gasket if not properly port matched. If thats your goal?

and unless you are planning on sending the crank rods and pistons Out to have them all checked dont touch it. just throwing new bearings on a used crank is not a good idea. Plus new arp bolt can throw the connecting rod out of perfect round cause high spots pre mature bearing failure. either leave it alone or have it 100% gone threw if your pulling it apart. Thats just my opinion.

 

Sorry I actually use 5w30 synthetic. I also did do some portwork inside the head but all the dirt i got from the front of the port fell to the back. They arent ported as much as you seem to think. you can see the gasket line on the head. I did no such "gasket matching", just cleaned up the garbage casting flash and worked on the roof corner to give the air a bit more of a straight shot. I did my reading enough to try it out ill get better pics when im done since these still need lots of attention.

 

I would stop removing material. It is VERY easy to ruin a set of heads, even if you think you're doing it right.

 

hm well i removed more and i bet it will make my car faster... my car only weighs 3100 at most

 

Ignorance at its finest.

What do I know?

 

You know maybe while he is blindly making the ports bigger he could throw a 3/4 race cam in the thing. Too bad he wasted all his time on the LT1 heads he should have gone for some 202 fuelies, finish it off with some nice cherry bombs.

Too many people post strictly looking for validation of what they have already decided to do without any research. We NEED to call them out on it though otherwise when people try and do research they see foolishness like this and think it was a good idea.

 

probelm with these heads Also is the roof thickness depending on the casting is REALLY thin and you could have fatigue issues down the road if you run a real strong spring. the rocker stud flanges can crack or worse completely rip off the head. my heads were ported by hand by a machine shop in texas. i bought em on the cheap. they are not the ideal casting numbers for porting and the roof is Dangerously thin for any extreme cam/valvetrain setup. Be Carefull!