Inliners International Forums General Discussion Engines Carbs Holley or weber

Yeah I have all those other parts. Just can’t get this Holley dial in.

How hard would it be for you to run hot water to the intake?

Would have to switch intake or weld water plenum under intake. My vac at idle is 22.
Today I went back to Clifford starting jets MainJet 48 squirter 31 power valve 8.5
and had lean stumble off beginning of gas pedal press. When I put in 9.5 it was better when I put in 10.5 it worked great but still had a slight one so I installed 49 main jet it was better but ended up leaving a 50 main jet in and I liked the 28 squirter and took out pink cam and left orange in. I am really happy with my seat of the paints one circuit at a time till I got my best results so far.
700 idle manual Trans 50 main jet 28 squirter 10.5 power valve and orange pump cam in #1 hole
Rebuilt chevy 250. Rebuilt head with Clifford's valves and runners cleaned up. Clifford long headers. Clifford older intake no water. Holley 390. X pipe dual 2.25 pipes with 3 chamber mufflers.

Have you tried all the stock jetting and power valves - and just put in a #37 squirter? Worked for me.

After all that tried every combo under sun but 35 squirter was biggest I tried and it was to rich. But now I think of it my main jet was a 53 at time so I could try that also. LOL
The leaner set ups worked best except it liked the bigger power valve. I ll give it a shot it isn't going to hurt I tried every other combo.

Again: the power valve isn't bigger.

Yes its a what vacuum it comes in at I herd please correct if Im not getting it. IM pulling 22 vacuum at idle so I cut it in half per Holley instructions. I put all my squirters in from 28 to 37 still has off cruising surge when u give it gas in one spot of throttle. The bigger main jet I install gets rid of it. Ive gone as high as 60 main but it just destroys power. The 3 chamber muffler has a certain tone u can feel and hear when u run a good leaner jetting and the power is good. Except for that spot or surge if u press gas pedal real slow u can over come it or get threw. There has been many other post I've read with real close situations but no one ever puts what cured there issue.

OK I have to take back some on my previous post because they were incorrect I did some more investigation today found out my fuel pressure at carburetor is one and a half pounds my vacuum gauge was not Sarah without broken got a new one not pulling 22 inches of vacuum pulling only 15 I’m going to first take care of the fuel pressure then I’ll take care of the power valve. So I just finished new fuel pump mechanical runs between 4 and 5 at idle. did change power valve to 7.5 per 15 in of vacuum but still has same thing same spot. So I guess I'm forced to look at power valve restrictor hole or channel?

So I take truck in to BILLS DYNO today. He's been doing carbs for 40 year and has equipment to measure air fuel. After all I did it ran good all the way over there but still had small nose dive when u stab gas pedal. He first set up idle a little leaner than I had rechecked timing and said it was good. He then visually checked and made sure squirters were shooting and he said the little nozzles on squirters on certain carbs he liked using squirters without nozzles he feels the shooting right in to gas stream and end up over rich condition so he put 25 squirter without nozzles and truck left his shop running great.
New fuel pump and resetting valves didn't hurt. Should have got a print out for horse power and torque but gear broke on dyno that runs that part of it. First time was around 200 hp and 275 torque at rear wheel original motor was 150 horse power I think but at crank.

Cool little vid-series on Weber DG series

https://www.youtube.com/watch?v=A44-xG3pKlY&t=11s

https://www.youtube.com/watch?v=fhYSo6u-Jm0&t=75s

https://www.youtube.com/watch?v=BfIH26O2Ijg

for the 32/36 guys, look at vid 2 and the sync link kit! may help drive-ability

I ran a number of experiments before discovering my biggest problem was timing. I still need to get my distributor set up, but higher timing made a huge difference.

It's still in pieces, but when I took it apart, I was running super rich. Front two plugs are very black. I'm backing off on things. I'll probably go to PV 8.5, MJ 51 (original). It's a gas guzzling pig as it stands.

Current settings (too rich)
○ Power valve 9.5
○ Main jets 54
○ 35 accelerator
○ Secondary jets 59
Timing now set to 18 BTDC (no vacuum advance)

That PV means that whenever you touch the throttle (reduce vacuum below 9.5) the PV opens - there goes your mileage. What's your vacuum reading at constant 60 mph?
Changing MJ size affects cruising mixture more than WOT mixture.
To get lean cruise mixture: small MJ.
To enrich WOT: enlarge PVCR.

I discovered that I had a 58 MJ in, way too big. Changed back to the original 51,sticking with 9.5 PV. I had originally found 51 pretty lean, but I was still using the 6.5PV at the time, and hadn't gone with more aggressive timing. Hoping that works. I seem to remember my vacuum being something like 22.

I give up

Hey, I don't know if this was intended for me. My engine is on a stand in the garage awaiting its new oil pan gasket. Hard to try anything out or get more data. I was changing jet between coats of paint.

The PV should be less than half the vacuum at cruising. I tried 10.5 at one point because the vacuum was around 22, but that didn't seem to help anything. I couldn't find my 8.5, think I have it to somebody. 6.5 was what the carb came with. Found what I had written down in my log didn't match the jets. Need to get this all back together and running so I can get back to the ignition. If like to try having that trimmed, but don't want to do it before I try these things out.