When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Cometic recommends .030-.060 larger than actual bore.
Im well aware, but If I went by their recommendation I’d be really fucked. This is .090 bigger than the bore.
High performance stuff you can’t go by that, have to measure the chamber width.
Even then this was a decent bit bigger than the side to side measurement.
Kinda hard to measure the diagonals when there isn’t a reference point on the other side.
Im well aware, but If I went by their recommendation I’d be really fucked. This is .090 bigger than the bore.
High performance stuff you can’t go by that, have to measure the chamber width.
Even then this was a decent bit bigger than the side to side measurement.
Kinda hard to measure the diagonals when there isn’t a reference point on the other side.
I use the head bolt holes as reference points to measure, they're a constant and act as a border. What heads are those with the chambers much bigger than the bores?
Not long ago, I started asking what the max chamber width was, just to get an idea of what I was getting into. I think a lot of the porters/head manf open the chamber up to boost the flow #s on paper. Having the chamber width doesn't tell you how the chamber sits in the bore, but you at least get an idea.
I use the head bolt holes as reference points to measure, they're a constant and act as a border. What heads are those with the chambers much bigger than the bores?
Its in the top post, tea tfs 235's. Id say the majority of aftermarket ls heads are this way, unless they are advertised as dedicated small bore i.e. fits 5.7's.
afr, tfs, prc, mamo, tea, mast, all have wider chambers.
Update to this... I decided to try an ls7 head gasket because Id like a bit tighter quench, and its in stock, vs 3-4 week wait.
Ive read that the ls7 gasket can have issues with the upper coolant holes, but my gasket (c5318) was already showing a hair of obstruction.
Figured the ls7 one was worth trying to see if it spaced the way I needed.
Well it worked out great, the ls7 gasket cleared the block holes better, and fits the head perfect too.
Only small issue was the bottom brass rivets. The head has a relief here that would probably clear, but figured it would not hurt to remove it anyway.
Especially since the dowels are only an inch away and will maintain the layers just the same, and the upper rivets are still in place.
09-02-2023, 05:56 PM
