for an engine build -- i have my set of ported/polished LT1 heads from a 97 camaro (no valve work)or i can get a set of new stock LT4 heads. not sure if theres much of a difference in the 2. anyone? thanks

 

The port volumes are larger on the LT4 and the ports are higher (I think about 0.1 inches). There is an LT4 intake to go with the LT4 heads which seems to be getting harder to find...

 

Would they perform better ported than an LT1 casting? Or at that point, considering they are pretty expensive for what they are, you would probably be better off going with an aftermarket brand huh?

 

moneywise if i was buying some i would go for aftermarket instead of stock, but i can pretty much get the lt4 heads with no out of pocket by doing a trade. i was just seeing if it was worth it or just stick with the heads i have and calling it a day.

 

AFR makes some great aftermarket LT4 heads w/ small combustion chamber volume (58 cc). Several aftermarket LT4 heads have large 65cc chambers.

WD

 

http://www.grandsportregistry.com/lt1vslt4.htm

 

one thing not accurate on that site lt1 doesnt have 4 bolt mains

 

All LT1 engines that came in the Vettes had 4 bolt mains.

 

some of the ones that came it camaros had 4 bolt mains as well.

as far as the lt4 vs lt1 heads like stated the port volume is higher and if you port the two the lt4 would flow more, but a stock set of lt4 vs a ported lt1 the lt1 will probably flow quite a bit more and i would stick with those, but if you are going to do more portwork then get the lt4 heads IMO

 

The LT4 ports are TALLER not raised, raised would mean the floor was located higher in the casting and that is not the case.

On stock displacement or very near it held within the pcms 7-7200rpm limit ported LT4s will be no better than ported LT1s, definete potential to dyno higher but will likely go slower at the track.
Judging by RESULTS I am as of yet unconvinced that ported vs. ported LT4s are better even on strokers.

For a street LT1 needing a small chamber IMO LT1 castings are the choice thik is for porting the 95 and earlier castings are prefered.

Pretty much the only reason I would look at any other head for a street LT1 is if you need a bigger chamber to get a target compression, then the Trickflows look good.

 

It is a 'vette site, so yeah, it's accurate.