I noticed at the track after i could not even come close to making my best times at the track .

It would come outta the hole fine but seem to be missing something while i got going .

After some reasearch i think my back barrels were not opening ??


I took off the air-cleaner and reved the engine up and
then i realized my secondarys where not opening but just a maybe 1/8th for a split second ........HELP ????????
Any ideas ??

Any help would be good thanks !!!

Mark

 

well, the secondaries will not open if you revv the car in neutral or park. it has to be under a load. check the tension on the AV spring on the pass side of the carb. it maybe too tight....

 

So what were your track times?

As was said, the air valve will not open (or not much anyway) just standing there winging the throttle; the engine has to be loaded, and drawing in enough air to suck it open. If it opens at all at no-load, it's a sign that the air valve tension is probably too loose already; such that when it is under load, it opens too soon before the engine is ready to flow that much air, and so it leans out and bogs.

Set the tension to about 5/8 - ¾ of a turn. That's usually about optimum on a 305.

I notice you don't list either of the things in your sig that actually attack that kind of car's performance limitations, but rather only a few little nibbles around the edge. Those important things are significant exhaust mods and a cam. You need to ditch the LG4 exhaust, every single piece from the heads to the street including the new cat if it's less than 3" in & out; and replace the entire system all at once, from heads to street, with something for some one of the high-performance cars such as L69 or L98. The easiest setup to deal with is the early L98 one, like for a 88 350 TPI. Remember: every piece, from the heads to the street, for some car other than the LG4: headers, Y-pipe, cat, cat-back. For a cam, look at the Comp XE256, since your car is an auto trans.

From your sig, I'd guess that you should be running somewhere near a 15.5 @ 89-90 mph.

 

Thanks for info guys ...........keep it comming ..........My best track time is 16.3 @90.1 MPH

I no very little about carbs ..........and i checked the spring screw and ?? not sure whats right ....wrong .

ya ......my exhaust is kinda messed up ......i am 50/50 decision about buying a 4th gen or keeping this car .

I took the high-flow cat off .........it kept leaking at the flange .

Car runs good .........but maybe it just needs some minor fix .

When i run it on the track ......it come outta the hole good then bogs abit and i hear a pinging noise ???

I know the back barrels are opening but how much ??

i hope this this info can help .

 

Hey Mark

Have you changed the secondary metering rods?...i did and i also installed a 1 inch spacer (McGuyers) from Crappy Tire for like $30 and what a difference.

 

??????? wha happen ???

hmmm NO .....but i guess i could ......thanks Kev !!