hi, I am running a holley 1920 on my stock 82 d150. It has 3.5 gears in the rear end and tires are 235/75 r15. I do a lot of city driving and once in a month I take a long 3 1/2 hour highway trip.

My truck is my toy, I tinker with it constantly. I would like to know what jet I should have on my slant 6 for best fuel economy. I have a 62 jet on it now, I had a 58 on it for a while (loved the economy), but the truck hesitated for a bit when taking off.

I would greatly appreciate any info on the subject.


thanks a lot...

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Slant power!!!
At least I try...

Try a 60.

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Casually looking for a Clifford hyperpak intake for cheap.

i have considered a 60.
I just was wondering if there was a better way to calculate the proper jet size?

Or does everyone go trial and error on this subject?

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Slant power!!!
At least I try...

Try it, read the spark plugs, try it again. There's no calculation to be done.

If the truck ran well with the 58 except for acceleration stumble, why not put the 58 back in and increase the accelerator pump shot by adjusting the accelerator pump linkage?

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The reason for my question is mainly because I read the posts on this forum a lot.... This is were I get my ideas on what I would like to do to my truck... Not all the ideas turn out great,, but I have fun learning and doing...

I have read threads were people have gone UP in jet size to improve fuel economy,,I want to make sure I'm moving in the right direction with jets and not the opposite.

I will try the 58 jet and adjust the accelerator linkage as you suggest,,

thanks again for the info and a bigggg thanks for all the time you invest (all of you) helping us with our problems,,

My truck runs a lot better thanks to this forum.

You have done more for my truck than any mechanic has.

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Slant power!!!
At least I try...

This advice from SL6Dan is really important. It can make a real big difference. He suggested this to me years ago and it really, really made a big difference! Take the slop out of the linkage and make sure the accelerator pump arm moves freely on the shaft. Sometimes folks don't oil that pivot shaft for the cam and it can build up rust making the accelerator pump bind and sluggish....

Mine is lightening fast and will break both P215-70R tires loose.

As you see, I run a #57.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

The linkage is never supposed to be oiled. Oil collects dust and grit—no good. If you feel you must lubricate the linkages, use a good brand of spray silicone, which is non-greasy and won't attract dust or grit.

There are three holes in the throttle lever where the accelerator pump linkage connects: outer, middle, and inner. The inner hole gives the shortest pump stroke. The outer hole gives the longest pump stroke. Before you try bending or otherwise tweaking any parts, try moving the pump link to the next-outer hole from where it is now to get a longer pump stroke. Also, while you have the carb apart to change the jet, grasp the accelerator pump drive spring between two pairs of needle-nose pliers and carefully stretch it so it's a little longer. Do it carefully so you don't spoil the spring tension. This will drive the pump diaphragm more briskly.

Also make sure your distributor vacuum advance is in good shape, hooked up to the correct port, and timing is set correctly. That all has a large effect on acceleration. And the thermostatic air cleaner assembly should also be intact, hooked up correctly, and working.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Off idle stumble indicates a lean out from the idle through the transition circuit which is 'covered' by the acc. pump shot...Dan's hit it on the head either change the linkage to increase the shot or bring the timing of the shot on sooner...The only other cause could be a vacc leak somewhere.
If you're running a stock motor the #58 should be enough for the smaller CFM of the Holley 1920...

-D.Idiot

ok. I will make the adjustments. Thanks for the info..

I have enough info on the subject, I'll take it from here.


Keep on slanting!!!

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Slant power!!!
At least I try...