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sutphen 30 01-28-2015 12:59 PM


Originally Posted by hogie roll (Post 4257284)
:rolleyes::rolleyes::rolleyes:


Well there you have it. Everyone should target 12.7 then because anecdotal evidence :rolleyes:

Can you read,,,I said this is what we saw.we tried a quick fix,it really didn't work.we sent the computes out to be reprogrammed.12.7 is a grenade waiting to happen.alot of 1075 owners don't have a clue what's happening in their combustion chambers,,hope they'll look and get a retune.

Baldie 01-28-2015 01:04 PM

Im very surprised its that rich, the cats must be pretty upset when its that rich.

Guess what EGT's the Ford ECOboost can resist for hours on end????

hogie roll 01-28-2015 01:09 PM


Originally Posted by sutphen 30 (Post 4257289)
Can you read,,,I said this is what we saw.we tried a quick fix,it really didn't work.we sent the computes out to be reprogrammed.12.7 is a grenade waiting to happen.alot of 1075 owners don't have a clue what's happening in their combustion chambers,,hope they'll look and get a retune.

I've read everything you wrote and you never made that clear.

sutphen 30 01-28-2015 01:22 PM


Originally Posted by sutphen 30 (Post 4257230)
Don't bet
The 2 I've put widebands on would run in the 13 at cruise and only drop to 12.7/9.real scary,tried adjusting regulator for more fuel up top and it did nothing but richen the bottom a little.ended up having Marc boos add some fuel.
And the timing they run,wow.I'd never tune like that.

:rolleyes:Seem pretty clear

47EXCALIBUR 01-28-2015 01:26 PM

Mercury runs the 1075 on the lean side. At WOT they get closer to 11.7/12.0afr ... cruise range is in the high 12s, low 13s .. Mercury, Whipple , Mark Boos are the only ones i know that have the software to make changes. the only thing you can do is crank up the fuel pressure from 60 to 62lbs to try and cheat the computer.. anything more the computer knows bc it monitors fuel pressure. Also the 1075 will go 150-175 hrs no problem, then just change springs,lifters, rockers and belts etc

TooLateVTEC 01-28-2015 05:13 PM

Some good info in this thread, and I thank you guys for it.

Speedracer29 01-28-2015 05:30 PM


Originally Posted by Baldie (Post 4257290)

Guess what EGT's the Ford ECOboost can resist for hours on end????

Probably about the same as a 1075.... They have about the same refresh schedule, don't they? :poopoo:


(Sorry, had to take the slow pitch down the middle. )

Keith Atlanta 01-28-2015 05:55 PM

What are the readings from 650-4000 RPM though?

phughes69 01-28-2015 06:54 PM

Here is my thought. The Corvette is direct injected so they can control spark knock WAY better, but the intercooler has a finite supply of cool water, so to compensate, just flood the engine.
The 1075 on the other hand has an unlimited supply of cool water for the intercooler, so they can run it leaner and with more timing.
And another thing is how good would it look for GM to say you have to have the engine in your $120,000 car rebuilt every 6-12 months, vs Mercruiser, say Oh you just bought 2 of our $80,000 engines, the maintenance schedule on those engines is a rebuild every 150 hours, but that is OK because we know you can afford it, and that is the accepted norm for your type of boating.

hogie roll 01-28-2015 07:39 PM


Originally Posted by phughes69 (Post 4257474)
Here is my thought. The Corvette is direct injected so they can control spark knock WAY better, but the intercooler has a finite supply of cool water, so to compensate, just flood the engine.
The 1075 on the other hand has an unlimited supply of cool water for the intercooler, so they can run it leaner and with more timing.
And another thing is how good would it look for GM to say you have to have the engine in your $120,000 car rebuilt every 6-12 months, vs Mercruiser, say Oh you just bought 2 of our $80,000 engines, the maintenance schedule on those engines is a rebuild every 150 hours, but that is OK because we know you can afford it, and that is the accepted norm for your type of boating.

Listen guys. The ZR1 is NOT direct injected. ZR1 is a C6. Direct injection made its debut on the C7.


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