305 carb on 350 Goodwrench engine

[cstephl]

Recently replaced an original 305 w/ a new 350 in my 85 C1500 2WD. Put the original quadrajet w/ new non-EGR Edelbrock performer on the 350. (original intake mfold was cracked) Set idle mixture for max vacuum, ign timing set correctly, and choke working OK, but engine doesn't seem to be carbureted right.

Difficult to accelerate smoothly from a stop, as engine rpm's tend to jump off idle. Have to feather the throttle or pickup will lunge forward. OK for drag racing I guess!

Also, when pulling my boat the engine seems to intermitently starve for fuel on long hills or hot days. (vapor lock?) Fuel filter and fuel pump are both new.

Is this 305 carb the wrong carb for my 350? is it tunable or should I just replace it? Any help with this is much appreciated.
Chris

[Pontiac1976]

Just a qustsion what does the truck idle at in park & what does it idle in drive with the brake peddle to the floor.

[reiners81chevy]

You might want to look into rebuilding the carb. sounds like its starting to show its age.

[BowtieGuy]

I agree, I would rebuild it or look into getting another one. Check through auto zone, I found a q-jet manufactured for a 1974 Chevy truck with a 350 for $175. It wont have any electronic hook ups but it works fine. I had one on my truck for a while and it worked great but I don't have any electric connections left on my truck either.

[Pontiac1976]

Well for that price that would solve a lot of problem for some time.
& you have carb for parts or to sell

[cstephl]

Thanks for the advice you guys. I just bought a Niehoff carb rebuild kit and will rebuild the carb tomorrow.

According to the local NAPA store, my17085227 carb off my original 305 is the same carb that was installed on the 350 in 1985. So the carb should work on my new 350.

Pontiac76- concerning your idle speed question, my old tach/dwell meter will not give me a correct reading when hooked up to the HEI. Not sure what the idle speed is, but it sounds like around 600rpm, and drops slightly when I put the trans in D while holding the brake. I am curious why you ask this question. When I put in the new gooodwrench 350, I did have some work done to my turbo 350 trans incl/ a new torque converter. Could this have something to do with my problem?

Thanks again for your responses to my questions.
Chris

[Pontiac1976]

I had asked that because it all most sounded like your in gear idle might be a little high. but this is just a guess. now a after market tach in side hear a trick that A racer Buddy did get a trailer wiring ( ends )for both side use the all in closed side except the ground open you wire that in hard under the dash then you hard wire the trailer side all open except the ground to the tach then you can un-plug it any time you do not want it there. works great great thing for race cars with big $ tachs.then you see if you ear is a prefect 10 on rpm so people can do that really well . I not bad but can be off bye 200 or 300 some times so tach work for me the best. Any how a little off the point.
If your idle in gear is a little on the high side it will lurch and your cam might have been up graded or TQ or just a rebuild for the carb is needed.
I was just trying to do the cheap thing first and easy. let us know how your rebuild goes. There not to hard take your time.

[cstephl]

I rebuilt the carb today. This made a definite improvement in the smoothness of the engine and was well worth the effort. The only things I found wrong were internal dirtiness of the carb and the float level was little low. But it sure improved the drivability of the pickup. Thanks agail for everyone's input.
Chris

[reiners81chevy]

no problem glad we could help out. The floats being low sounds like the truck was starving for fuel and was basically falling on its face.

[cstephl]

I think you are right on about the float level reiners81. I just pulled my boat 150 miles and didn't have the intermitent fuel starvation problem on any of the big hills. The engine runs better throughout the rpm range and idles much more consistently than it did before I rebuilt the carb. There was 100,000 miles worth of crap in that carb. The 350 goodwrench is a sure good towing engine. Anybody know where I can get a portable tach that works on the HEI distributor?
Chris

[reiners81chevy]

You can use any tach. I have a Autometer Pro Comp 5in Tach hooked to my HEI. In my other truck before an old lady pulled out in front o fme and totaled it, I had a Sunpro 3 3/8 Tach with HEI. All You need is the right connector to fit on the lead on the cap. And everything else is straight forward.

[Pontiac1976]

Yes any tach will do as said .

[cstephl]

OK, thanks. When I hooked up my very old dwell/tach to the tach terminal on my HEI it seemed to read about 1/2 scale (indicated about 300 rpms) so I thought there was something wrong. I will try it again when I get back home. Maybe I had it hooked up wrong.
Chris

[Pontiac1976]

I got ask you is there a switch on the very old dwell/tach box for 4,6,8 cylinders, and a lot of tach will have a switch for the same thing should all was be switched over to the right set up be for hook up to read right.

[cstephl]

When I get back home in a couple days i will give the old tach dwell meter another try. I had it on the 8 cylinder position and the low rpm position. Maybe I need to get a little better understanding of my meter since I haven't used one in about 25 yrs.
Chris