Alwyn678

Anyone else experience this?? Usually I let it run for about 3 to 5 minutes before driving but there is No doubt it is Cold natured

virtue4u

My car used to be that way when I first bought it until I opened up the thermostat housing and found that it did not have one. Now it warms up normally.

GrandSportC3

What thermostat are you using??

:cheers:

Olivier

Alwyn678

I am not sure?? I have never checked or changed it....Think I need to look at it??

sb69coupe

Check your thermostat to make sure: a) there is one installed and b) it's not jammed open. What kind of carb are you running? What kind of choke? Does your intake have a heat crossover passage? Are you running an exhaust heat riser on the passenger side to help warm the manifold? These were all the things that GM spent lots of money paying engineers to design in order to achieve good driveability from our beloved Corvette. If all those things have been removed, it's logical to believe that the car won't warm up as well as it was designed to.

These old carbureted motors don't warm up like modern fuel injected motors do. It's tough to get a properly atomized fuel charge when the intake and carb are cold.

Shannon

Alwyn678

yes it had a heat crossover.....do not know about the riser..I am running a Demon carb.I am going to check out the thermostat as well

Sigforty

My car was always like that. Even with the electric choke. I had to let it sit for a while longer at high idle before I kicket it back down. The only good thing is it only happens in the winter and I do not drive the car that much then.

Mark B.

TedH

Lars helped me out some on my car. After installing cylinder heads w/out heat cross-over passages, installing headers with dual exhaust pipes and w/out the heat riser (and w/out the converter), and removing the three thermal sensors that were in-line with my emissions vacuum hoses, my car took much longer to warm up.

I had to improve choke performance and overall performance/driveability resulting from the introduction of the heads and headers (the car was running lean). Lars sent me replacement primary metering rods and main jets and he rebuilt my carb as it was in need of serious attention. The car still takes a while to warm up but it behaves better as it warms up (Lars richened it some so it has more fuel than it did before and choke operates properly due to the rebuild).

I think I run a 185 degree thermostat. I also employ use of a hot air stove on the dual snorkel air cleaner to use warm air from around the left header during warm-ups. It doesn't warm up as quickly as with the old '882' heads with heat crossover but it's worth it for the power gains (heads and headers).

Ganey

Nature of the beast. I always run blocked heat riser if present in intake.

A working choke will help those concerned about it. You need a 180 thermostat.

UKPaul

Hi Alwyn,
How's life? I ran mine up a couple of days ago & we're currently at around freezing point. It ran pretty well while it warmed up with only the odd hesitation. The heat riser has been removed & the passage has been blocked off. I've got a 180stat, no EGR & the Thermac is in place (the pipe to the heat stove & the stove itself was missing). Without the pipe to the heat riser warming up wasn't good, but fitting the pipe & tying it to the ex manifold with a bit of wire (OK, it's a Bubba fix but it looks neater than a rusty old tin heat stove :) ) made a big improvement.
Hope this gives you some clues!
Paul

Alwyn678

Hey Paul......Thanks for the Information..I am gonna check it out this weekend.........Hope things are going Well for you!!

UKPaul

Hi Alwyn,
Things are OKish (the very day that I started my planned winter jobs on the Vette we got our 1st proper snowfall in 12 years!! What sort of luck is that? :rant: ).
I must be cracking up, I can't believe that I forgot this as the Bonnie does the same thing ie. it's a real pig to warm up in cold weather, but it's as good as gold in the warm weather. The problem is the carburation as it's got emission controlled carbs on it. With open pipes :D the mixture is very slightly on the lean side just off of idle (I've richened up the main & needle jets but need to alter the throttle slide cutaways to get it correct just off the idle position. As it runs great when warm, & is only a problem when starting from cold in very cold weather, I cannot be arsed (an English term) to sort it out). On a cold morning it runs in exactly the way that your Vette does, so it may be worth checking if your mixture is set slightly lean.
Good luck,
Paul

Alwyn678

Good point I will check that as well.......It will be SUPER cold here this weekend so It will be a good time for testing :cheers: :cheers:

PB82CE

I run a 180, and my heat works great in the winter. :yesnod:

Fevre

:yesnod:

I ran a 160 for a while and it just did run as well and very little heat for those late evening top down runs.