[76FJ40]

My son and I both have 40s with Weber 38 DGAS carbs from TPI. TPI's catalog says that they rejet the carbs for the 2F, but they both run rich. I've called TPI a couple of times to see what size jets they use, but I haven't gotten a straight answer yet - last time I called they told me that the jets were 55s.

Can anyone offer a recommendation on replacement jet size?

 

[rabid]

I have heard a lot of people with the 38's saying that they run rich. I know some people put in a fuel pressure regulator to help slow things down some.

 

[76FJ40]

Thanks for your help. I have a fuel pressure regulator in mine and it's adjusted to 3 PSI but it still runs rich.

 

[Lord Baskerville]

Do you have a header?
I could not even adjust my 38/38 until I installed the header that was back ordered a week. This was 8 years ago...
Just put a 38/38 on a friends truck and it runs a bit rich but sounds and performs great...
We are going to try it at the Badlands IN before any changes are made.
Mine is reged to 2.5 PSI his isn't yet.
Also, a weak spark may lead to a rich condition with the extra fuel the 38/38 gives you...
Just an idea.

Cory

 

[76FJ40]

Thanks for the help. Both Cruisers have headers and the TPI performance exhaust. I replaced my distributor with a non-USA model (40+ degrees total advance) and that helped a lot. My son's also improved significantly once we got the ignition up to full power and replaced his "retard" distributor with an "advance" distributor. I'll try lowering my fuel pressure a little more to see if that helps.

Thanks again for your help.

 

[Richard Nelson]

I am Lord Baskerville's buddy that installed the 38mm weber recently. We also installed a header and 2.5" exhaust at the same time.

The truck <I>still</I> ran rich! I have a Mallory electric fuel pump and a regulator so I can regulate down the pressure significantly. I will let you know how it works out.

-r

 

[hi50]

These guys might be able to help: http://www.webercarburetors.com/ . Or, http://www.worldpac.com/index.html . They might need to know your altitude, engine mods, etc. Good luck.

 

[DonM]

For those of you with the fuel pressure regulator--do you run it same on street as on trail?

 

[Lord Baskerville]

Street, you mean we can drive these on the street
I can but rarely drive mine on the street.
I do use 2.5 to 3 PSI everywhere.
The only time I have starved for fuel is if i rev WAY too much...
Such as pulling a stuck truck from the mud and standing on it in the same mud.
I am either floating the valves or starving for fuel!
I think it is fuel...
Built in rev limiter:emb:

Cory

 

[SpaceGhost]

weber 38 dgas

I too bought a (tuned for me) weber from TPI. Generally I like Bob and his staff so this isn't a rant on them. I took Bob's advice and did all the things he told me would be needed, electric pump, filters before and after pump, a regulator, advance dist (which I had along with a full bore Jacobs), header. The weber ran rich at even the lowest regulator setting (that would run) which was about 1 for the trail and at least 4 for any on road/hwy driving. Too low and it would starve before you could get into 3rd gear. I ran the included little k&n filter and then later adapted to the stock airbox.

No matter what adjustments I did (from the install sheet) it ran rich. I called TPI on several occasions thinking maybe it was jetted for below sea level (although Indy is only a few hundred feet above) and not once even when asked directly would/could they tell me what jets were in my carb. They actually gave me the impression that is was normal and I was just to damn worried about it.

It is sitting in a box in my garage (short the accelerator pump and diaphram I so stupidly loaned to a friend/chump that couldn't get home the 100+ miles without it). I don't miss it at all, as a matter of fact I have gotten pretty good at spotting a weber on the trail.

Everybody that I know that has one (weber) is in denial (hell I was too after spending the $400 for a turd carb) and maybe some will display that after they read this. Hopefully others may see the light.

Today (but not for long) I am running a 2bbl non-usa Asin, with a stock airbox and k&n. Major improvement in all areas, but still a carb that was built to run at minor inclines. Many of us have built rigs that can traverse much bigger obstacles than a carb can handle, especially a weber.

Soon I will be sportin' a TBI on my 2F, ripped the whole system off a 89 GMC 4.3 yesterday. Have a Downey adapter that will be used as a pattern for a more affordable option which I plan to make available to others. (Just not likely to be posted in the For Sale section here since I don't make the rules, and certainly can't break them, right SB.)

The time for fuel injection for all Cruisers has come!

I gotta get this soapbox fixed before I get hurt!

Mike "SpaceGhost" Smythe

 

[Lord Baskerville]

Mike, I half agree and half disagree with ya :flipoff2:
I have the makings for FI here in the shed Holley or 4.3 Chev.
I decided to stay with the Weber cuz it doesn't let me down.
I have run at idle or reved for extended periods of time with the weber and it won't die. I have oil fouled plugs before angles have hurt me.
Keeping the Weber based on the KISS principle :rasta:

If I didn't use a Weber or FI I think I would find and old 500 CFM Quadra-Jet and adapt it to the 2F.
That would work great.

Same problem....Mult. solutions...Ain't life grand:beer:

Cory