Plenum & Injector Housing Porting - Page 11 - ZR-1 Net Registry Forums

jss06c6 · 03-13-2019

Spark Table and Fuel Table, secondaries open.. Black curve is new, red curve is old. AFR hugging 12.8:1..

XfireZ51 · 03-13-2019

Quote:

Originally Posted by jss06c6

Spark Table and Fuel Table, secondaries open.. Black curve is new, red curve is old. AFR hugging 12.8:1..

I found that the area ~ 4500-5500 rpm (max torque) is where the LT5 is prone to detonation. Beyond that, its pretty resistant to knock. The further u crank up timing at the top, the more u just see power drop, but w no indicated knock.

jss06c6 · 03-13-2019

Thanks Dom.. How far can I push rev limit without risk to the engine? Seems it wants to at least get another 200 rpm w/o any issue... Not chasing a number by any means, just curious about when the engine begins to roll over.. Porting heads would seem to add more "headroom" as well..

XfireZ51 · 03-13-2019

First of all, this is absurd that I try to reply and end up witha Forbidden 404 message. And not consistently. When is this getting addressed?

Steve,

I set the shift light at 7200 and fuel cutoff at 7400. From the last dyno runs I did several years ago, power peaks at 68-6900rpm. I also roll off timing after 7000rpm and fatten up fuel at that point also.

jss06c6 · 03-14-2019

Perfect, thanks Dominic!!

Sent from my XT1585 using ZR-1 Net Registry mobile app

03-13-2019	#103
jss06c6 Join Date: Aug 2015 Location: Magnolia, Texas Posts: 884	Re: Plenum & Injector Housing Porting Thanks Dom.. How far can I push rev limit without risk to the engine? Seems it wants to at least get another 200 rpm w/o any issue... Not chasing a number by any means, just curious about when the engine begins to roll over.. Porting heads would seem to add more "headroom" as well..

03-13-2019	#104
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,709	Re: Plenum & Injector Housing Porting First of all, this is absurd that I try to reply and end up witha Forbidden 404 message. And not consistently. When is this getting addressed? Steve, I set the shift light at 7200 and fuel cutoff at 7400. From the last dyno runs I did several years ago, power peaks at 68-6900rpm. I also roll off timing after 7000rpm and fatten up fuel at that point also. __________________ [SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX Last edited by XfireZ51; 03-13-2019 at 11:31 PM.

03-14-2019	#105
jss06c6 Join Date: Aug 2015 Location: Magnolia, Texas Posts: 884	Re: Plenum & Injector Housing Porting Perfect, thanks Dominic!! Sent from my XT1585 using ZR-1 Net Registry mobile app