Just wanting some (supported) opinions.
Unfortunately I never anticipated going full sleeved to 84.5mm...before I had the head work done. As the head is now(B16): DPR valve springs, DPR valve job (ITR intake valves porcilin coated-oversized SS exhaust), the head has also been P&Ped and port matched.

Now, the question is: Should I go back and get the combustion chamber modified to correlate with the oversized (84.5mm) LS block?

 

if you've already got headwork, i wouldnt mess with it. The benefits aren't worth the cost. But if you are going to get head work, i do recommend it.

 

Yeah, I've already done all the work mentioned.... Just wondering how much (and what) benefits it would net.

 

mainly it would give you a quench area that matches the bore, important for combustion quality and detonation resistance. Opening up the bore brings the sharp edges that surround the combustion chamber out of the combustion area, thus preventing detonation. Downside is, opening the chamber lowers compression, though that could be a possible upside for you depending on your situation.

 

search archived topics..there was a really good thread on this a while back

 

.....is wondering the same damn thing

 

in... for updated answers

 

VaporTrail pretty much broke it down to the bare facts. My humble opinion is to go ahead and do it if your gonna have the engine apart, cause of the detonation resistance. but if you have a standalone of some sort with a good knock sensor, then just kep tabs on it.

As far as mixture quality goes, that is a long discussion, and it's 3:18 am, so no book typing from me.

 

Talked with viren....Thinking of just leaving as is. Noticed someone with similar setup running 500hp. Thats inspiring. We'll see how it goes....I plan on doing extensive tuning to prevent any unwanted outcomes
Just for reference, what is the "going rate" for combustion chamber modifications

 

I'm doing the 84.5 thing too. I think with my head (b16) I'm just going to round off the cc edge by hand. Nothing major, just mark it and radius that corner to remove a potential hot spot.

steve

 

....thinking the same.