Offshoreonly.com - Blow thru carb....chill at idle or no??

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Quote:

Originally Posted by MILD THUNDER (Post 3830391)

I wasn't talking about the hot air for the choke. I was talking about the heat risers they used to put in the exhaust manifold. It was plumbed directly into the air cleaner assembly, and fed warm air back into the carburetor. Some actually had ''heat riser'' valves, that went between the exhaust manifold outlet, and the exhaust pipe. When the engine was cold, the valve would shut, forcing warm air from the exhaust into the air cleaner. Once the engine warmed up, valve opened, things went back to normal. The valves became problematic themselves, and most got welded open, or removed. They then went with just a tube that collected heat from the manifold, with a thermostatic flapper on the air cleaner. When the engine was cold, flapper door shut, focusing on sucking heat from the hot air tube, which mounted to the manifold.

High power airflow wasn't a concern. Because with the old quadrajets, when the choke was engaged(cold Engine), the secondaries would not open.

But thank you for attempting to correct me.

Not correcting just elobrating
+1 absolutely... good call

Quote:

Originally Posted by tunertech (Post 3830402)

Not correcting just elobrating
+1 absolutely... good call

edited my post. Thanks for the insight...good info.

I just let mine warm up for 5 minutes and they run just fine . :whistle:

Quote:

Originally Posted by ICDEDPPL (Post 3830063)

GM, Ford etc. They Run coolant thru the throttle body for idle quality when cold, that may tell ya something...

That is more to keep it from icing up in cold weather.

you say your friends idles like crap...what is his setup ? timing at idle, who did the carbs ? in the procharger box ?

Quote:

Originally Posted by ezstriper (Post 3829982)

I was running a prosystems blow thru carb built for my 509, did not idle bad at all most of the time....every now and then acted up...not sure what to blame that on...now I do run timing locked @ 28 and a digital 7 MSD ignition with start retard. I do run water thru mine all the time..but at idle flow is not much...am currently working on my own port EFI so let you know in the spring how that works out....

Air charge probably has nothing to do with it. I too have locked out my distributor, though i'm running 33* since Victor Jr.s like timing. Mine idles like a dream. 248 @ 50 with 112 center. 550 solid roller. The Novi 2000 is pushing about 14lbs boost. The issue i have is the transition into the enrichment circuit. Carb Shop did a good job overall. I too am thinking of the Holley fuel rail closed loop system. Is this what you are doing? If so let me know how that goes.

i used to work on large high speed diesels, we would run intercooler water full bore, run fast then return to idle. problem that occured, humid air on the water around boat running across intercooler would lead to water droplets bouncing in intake ports. these would lead to damaged valves and piston crown - thermal shock.

Quote:

Originally Posted by keith2500hd (Post 3831012)

thats what i was geting at when i made a post about he wont need meth injection with all the condensation..:party-smiley-004:

no on the holley EFI using a dart EFI intake, 1000 cfm+ throttle body 90lb injectors, our own megasquirt computer/tune, will run ignition/timing curve as well thru it...have a laptop based tuning software we use, I did talk to holley, professional products, fast, none of the self learning deals would work with the procharger as they were, need custom tuning, won't know anything till spring...