Not to pick on gbauer, so don't take it that way, but
I think gbauer's problem with hesitation was a lot of things that needed to be sorted out & not really a problem of using a non heated intake manifold.
His engine sounded totally lean @ first, carb jetting, accelerating pump sizing, mixture screws you name it, all seemed to be off.
I never had a problem with non heated intake manifolds, Offy or Cliffords, winter, summer no problem's what so ever.
Yes, it was a little cold blooded when first started, but that was not much of a concern, drove it everyday that way, & with no choke, just blipping the throttle.
I think gbauer, can go back to a non heated intake manifold after it gets all sorted out I bet there would not be any difference in driving, after it is partially wormed up, not even full running temperature.
Yes, if you have a heated intake manifold you will be able to take right off when completely cold, but like I said, once it's warmed up, never had a problem.
MBHD
Problems I've run into that made mine run bad:
-Trans vacuum line was OK up top but the end wasn't connected. All sorts of issues there.
-Power valve was bad.
-Power pump check valve bar had fallen out and ball was rolling around in the diaphram.
-Power pump was not adjusted properly
-Timing was off
-Vac advance needed adjusting
-squirter size was off
-Jets were off
-Electric choke needed adjusting
...just a few problems...
It was a lot of things together that made it really difficult to find them all. Some were self-inflicted. Others just happened. Still others were like that when I got it (no joke. Trans never shifted right until that hose was connected. I know it was off since day 1).
All that said I still like my heated intake. The PES is fine for track use but my little auto cruiser is just more suited for a heated intake. The kids can be a bit impatient when it's warming up (2 and 5 years old). The two year old cries like the world is falling apart if i start the car and he's not in it.
...but if I had a track car the PES would be the intake to get.
...then again if I had a track car a 250 probably wouldn't be under the hood. Even I'm not that much of a glutton for punishment!
I'm definitely NOT knocking the PES intake! It's a good piece of engineering. It's just not right for me.
