Port and polish
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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Port and polish
Be interesting to see what kind of bump in HP results from doing a P&P.
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Very good question as the heads are such an important factor in a NA motor. All these possible performance enhancers will be dependent on the "crackability" of this generaion of Corvette's ECM or whatever they call it this time around. Could the C8s ECM be sophisticated enough to make fueling adjustments etc. for bolt ons and other mods on its own and not require any after market tuning devices? Who knows?
Le Mans Master
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From: North Dallas 40 TX
Very good question as the heads are such an important factor in a NA motor. All these possible performance enhancers will be dependent on the "crackability" of this generaion of Corvette's ECM or whatever they call it this time around. Could the C8s ECM be sophisticated enough to make fueling adjustments etc. for bolt ons and other mods on its own and not require any after market tuning devices? Who knows?
Race Director
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I wouldn’t expect it to be much different than on the LT1. Camshaft will be the biggest gain imho as they already improved the intake and exhaust manifolds. The cam is tiny to comply with emissions, I’d allow it to breath deeper by hanging the valves open longer as the heads already flow very well.
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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That is why I've decided to stick with the NPP option. Just don't feel like ripping things apart on a new engine.
E-Ray, 3LZ, ZER, LIFT
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Reminded when we were sponsors of the Richard Petty NASCAR Team and I was talking with their new engine builder. (At the time they were building and testing engines in Level Cross. Dale Inman, who I mostly interfaced with said on one visit, go talk with our new engine builder he sounds like you! I recall I would pull into the shop with my '88 Vette and Dale knew I was a gearhead. Richard would always walk from his house and come and say hello- great down to earth folks!)
Recall looking at a new set of closely spaced very fine machining steps in a set of cylinder heads he had just received. He told me he had not found it helps but he still polishes the intakes! Recall when I built an Olds engine for my first car, a '41 Ford Coupe, a friend taking machine shop did a valve job and polished the combustion chambers so it looked like a mirror! However the heads and manifold that came in some 30 boxes with the 502/502 BB I put in my street rod had CNC port matched intake and exhaust. Not sure polishing those CNC machined passages helps. Perhaps some shaping around the valve guides might IF you had tested and proven it was advantageous. Expect folks like Katech have done that and with higher lift, longer duration cams know where removing material or polishing helps.
Last edited by JerryU; Aug 31, 2019 at 12:58 AM.
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From: altered state
St. Jude Donor '05
Im betting theheads, intake exh is pretty good to start with so money wise it may not be worth the gains.
Bet most just add a blower and call it a day.
Polishing ports even cnc never netted anything on the bench. Could drop or gain 1-3 cfm thats it.
Back when factory parts were real old tech you could do some basics and be the hero they were so bad. Today its quite the opposite, GM has done most the work for us.
Bet most just add a blower and call it a day.
Polishing ports even cnc never netted anything on the bench. Could drop or gain 1-3 cfm thats it.
Back when factory parts were real old tech you could do some basics and be the hero they were so bad. Today its quite the opposite, GM has done most the work for us.
