73-454

Thanks, Fixed the stalling-out at high speed by simply removing the small 1” fuel filter in the Qjet, I can’t believe GM installed such a small filter in a 454. I will be installing an external fuel filter. Every-one I have talked to regarding my overheating at hiway speeds and runs normal in city every-one claims it should be the opposite. I did remove the small spoiler for repairs I can’t believe that little item will have such an effect on airflow. I will install the spoiler and test again before I remove the Rad. No leaks anywhere, new rad hoses, new hi-flow stat, fluids toped-up.

The Dude

I think your highway overheating problem will go away with the reinstallation of the chin spoiler. C3s are bottom-breathers. If there's nothing there to deflect air up and through the radiator you will run hot. Glad to hear you have the other issue addressed. Those puny little in-line filters that come in the Q-Jet are horribly restrictive and should be removed.

[EDIT] And replaced with a high-flow in-line unit of some type. Our carb friend Lars has put out a very informative paper on fabricating steel pump-to-carb lines incorporating an in-line filter. Very good stuff.


[Modified by The Dude, 11:47 PM 2/27/2002]

still-learning

For my wimpy 350 :jester the chin spoiler made a huge difference. I had removed it because it was all cracked up. The running temperature went up noticeable during highway speeds. When I replaced it w/ a new one the temperatures went back to normal.

Just my experience...

Tim M.

73-454

I hope that fix will work, I would hate to take the rad out and get it dipped at rad shop. I just finished detailing the engine. I will keep you posted after I install the Chin spoiler.

gerry c

Replace the stock filter in the carb very soon please. That little filter works just fine. If you are concerned about clogging, put a external on also. DO NOT drive much with no filter. You could be throwing a lot of crud right into your QJet. If you do replace the stock filter, there are two types, one has one way valve in it, check to see if you need it or not.

If you really wantto protect the carb, put on an external and try to find a sintered brass internal filter. That is what I run on my 454 truck and it flows fine. That truck sees WOT for extended periods of time when I pull a 11,000 pound trailer.... big steel gooseneck with four large (17 hand) horses in it.

DavidOrr

For what it's worth - and maybe someone else has suggested it.

My small block used to overheat on the highway and ran great in town. Turned out to be a timing issue.

Like I said for what it's worth, maybe something to check out.

-David