warmer better then cooler
Thread Starter
Team Owner
Joined: Nov 2004
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From: Sorrento Italy
warmer better then cooler
hi, why engine (570hp 406ci) in my C3 only gets really performant and quick after a good launch on a motorway on full or nearly full throttle? instead even when warm after switch on it's a bit lazy and anyway i do not feel it in its full stregth? is it normal? i mean the more and the faster it goes the more and the faster it wants (and seems to me...) to go, is it normal? i have a tvr griff with a 5 ltr (tuned to nearly 380hp) that gives the best after got warm but not too hot, instead after a good launch and getting really warmed up it gets a bit lazy and on my opinion it looses part of the strength...any ideas? thanks/Giu
Race Director
Joined: Nov 1999
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From: Foxfield CO 1970 Convertible
Maybe when there is some carbon buildup in the cylinders, that makes it seem "lazy". It might be mis-firing. When you take it out and give it a good launch, it blows out the carbon (gets rid of it) and makes the engine fire better.
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Team Owner
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From: Sorrento Italy
..infact the builder (american speed co.) adviced me that this engine would perform better if time by time i give it a good launch at full throttle when sometime ago i told them i found black carbon dust in the outlet of the side pipes...the matter is also you need to have full of street ahead to launch this beast, sometimes it scares me, it can spin (stock) rubber even when cruising and you floor the throttle... 
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
Originally Posted by panic
hi, why engine (570hp 406ci) in my C3 only gets really performant and quick after a good launch on a motorway on full or nearly full throttle? instead even when warm after switch on it's a bit lazy and anyway i do not feel it in its full stregth? is it normal? i mean the more and the faster it goes the more and the faster it wants (and seems to me...) to go, is it normal? i have a tvr griff with a 5 ltr (tuned to nearly 380hp) that gives the best after got warm but not too hot, instead after a good launch and getting really warmed up it gets a bit lazy and on my opinion it looses part of the strength...any ideas? thanks/Giu
Thread Starter
Team Owner
Joined: Nov 2004
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From: Sorrento Italy
Originally Posted by jackson
Carb likely rich ... need to have a pro map carb's fuel circuits ... rejet & tune.
Pro
Joined: Jan 2002
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From: Marietta ga
It sounds like you are running rich. You are probably getting carbon build up on your plugs. You might need more initial timming or you might need to adjust your idle bleed screws and throtle plate position at idle.
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Melting Slicks
Joined: Nov 2000
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From: Bogart GA
Sounds to me like you are running a large cam with a high stall converter. Is this a new engine set up? What rear gear are you running? What is your transmission? TC stall? Cam specs? Rear tire diameter?
Melting Slicks
Joined: Nov 2000
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From: Bogart GA
If you want to clean out the top end, dribble some water into the carb after you warm up the engine. Don't dump it in, just enough to make the engine sputter. Then rev it up while doing it. You will see lots of crap shoot out your tale pipe, kinda like after a long night of beer drinking.....
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From: Sorrento Italy
Originally Posted by KJL
Sounds to me like you are running a large cam with a high stall converter. Is this a new engine set up? What rear gear are you running? What is your transmission? TC stall? Cam specs? Rear tire diameter?
Safety Car
Joined: Sep 2005
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From: Orange County Ca
Some engines just run better when real hot. Nothing is concrete for all engines. On the dyno, I make the most hp when running rich. The dyno guys changed my main metering rods in the q-jet to run leaner @ the hyperthetical best air/fuel mixture and it lost power. What is Hot?? A friend of mine likes to run his sb at about 160 deg. I think this is too cool. My bb runs at 190 to 220. If you need to run real hard regularly to keep the crud out, then somthing is wrong. Too rich, too cold, burning oil, cold plugs, etc. Normal driving on a normal engine will not clog up anything enough to really affect performance. Of course, I don't ever pass up a excuse to goose the old bugger, like on a freeway on ramp.
Last edited by Sayfoo; Jan 23, 2006 at 10:46 PM.