Corey does his magic - Page 3 - ZR-1 Net Registry Forums

XfireZ51 · 01-15-2016

Graham,

Any thoughts on the Mercury Marine heads mated to an LSx block?

grahambehan · 01-15-2016

Quote:

Originally Posted by XfireZ51

Graham,

Any thoughts on the Mercury Marine heads mated to an LSx block?

Should be good if they ever get to fruition, I hope they do and look forward to working on such an engine.

Graham.

XfireZ51 · 01-15-2016

Quote:

Originally Posted by grahambehan

Should be good if they ever get to fruition, I hope they do and look forward to working on such an engine.

Graham.

Would make for an interesting alternative to the LT-5.

grahambehan · 01-15-2016

Just a few comments on information stated earlier in this thread:

The LT5 was a premium fuel recommended application, so the production released ignition timing was about 5 degrees from borderline detonation.

In test 1 form, as installed in vehicle with vehicle intake, exhaust and calibration the 1993 engine made 405 hp SAE corrected.

In test 20 form, max potential, with open inlet, headers and LBT/MBT it made 445 hp.

So there is easy power to be made from ignition timing and fuel on a stock system, add headers and more timing can be added, reducing back pressure tends to make the knock limit higher.

Graham.

XfireZ51 · 01-15-2016

Graham,

When dyno tuning my motor, I have found that knock appears to occur at ~4500-5500rpm range. However, beyond that the LT-5 appears to be knock tolerant. I've had WOT timing up around 34-35d with no indication of knock occurring at that level. Just a loss of power. AFR is ~ 12.8:1. How does that square w your experience and expectations?

grahambehan · 01-15-2016

On 93 octane fuel I would agree with the above.

Graham.

XfireZ51 · 01-15-2016

Quote:

Originally Posted by grahambehan

On 93 octane fuel I would agree with the above.

Graham.

Yes it's 93 Octane 10% Ethanol. Which brings up the question of doing E85 on an LT-5.¢

Fully Vetted · 01-15-2016

Quote:

Originally Posted by 32valvesftw

I picked up my 91 in March, it had Bola exhaust on it but was otherwise stock as far as I know. I removed the resonator and added an X pipe, then gave it to Corey H for headers and tune. Just got the dyno results 382 whp / 373 tq. Im impressed, I haven't driven the car yet but I can't wait to feel the difference.

Congrats! Yes, Corey is def an ace when it comes to tuning. We're fortunate to have him in our backyard. You'll love the difference.

32valvesftw · 01-17-2016

The tires do appear to be slipperier, than they were before.

01-15-2016	#21
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,698	Re: Corey does his magic Graham, Any thoughts on the Mercury Marine heads mated to an LSx block? __________________ [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

01-15-2016	#24
grahambehan Join Date: Feb 2013 Location: New Concord Kentucky Posts: 181	Re: Corey does his magic Just a few comments on information stated earlier in this thread: The LT5 was a premium fuel recommended application, so the production released ignition timing was about 5 degrees from borderline detonation. In test 1 form, as installed in vehicle with vehicle intake, exhaust and calibration the 1993 engine made 405 hp SAE corrected. In test 20 form, max potential, with open inlet, headers and LBT/MBT it made 445 hp. So there is easy power to be made from ignition timing and fuel on a stock system, add headers and more timing can be added, reducing back pressure tends to make the knock limit higher. Graham.

01-15-2016	#25
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,698	Re: Corey does his magic Graham, When dyno tuning my motor, I have found that knock appears to occur at ~4500-5500rpm range. However, beyond that the LT-5 appears to be knock tolerant. I've had WOT timing up around 34-35d with no indication of knock occurring at that level. Just a loss of power. AFR is ~ 12.8:1. How does that square w your experience and expectations? __________________ [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

01-15-2016	#26
grahambehan Join Date: Feb 2013 Location: New Concord Kentucky Posts: 181	Re: Corey does his magic On 93 octane fuel I would agree with the above. Graham.

01-17-2016	#29
32valvesftw Join Date: Jun 2015 Location: Texas Posts: 530	Re: Corey does his magic The tires do appear to be slipperier, than they were before.