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Author Topic:   question, holley 500 jets
way2fast
Dirt Maniac

Total posts: 104
posted September 29, 2003 01:50 AM  
going to try a 500 holley on our mini, has pretty much stock bottom end, head milled.100 any suggestions on starting jet size? , 420lift hyd cam.

b4racing
Dirt Forum Champ
Total posts: 626
posted September 29, 2003 04:30 AM  
I think you are shooting your self in the foot with it. if you are running a 3/8 or smaller it will be lazy off the corner and not be real crisp. Just my .02 though. BObby

NH RACER
Dirt Roller

Total posts: 8
posted September 29, 2003 07:36 AM  
You can run the Holley 4412. However you will need to get the restrictor kit from Racer Walsh. We have the 4412 with 68 main jet and 3.5 power valve and 1 inch spacer.

CARB RESTRICTOR KIT:
The Holley 350 & 500 CFM carbs are designed for use on a V8 and will run too rich on initial acceleration in a 4 cylinder engine. Our kit will eliminate the bog by reducing fuel flow through the metering block.
1218 CARB RESTRICTOR KIT $9

[This message has been edited by NH RACER (edited September 29, 2003).]

speedyd1
Dirt Maniac

Total posts: 170
posted September 29, 2003 01:44 PM  
not to mention the fact of pullover at high rpm. holley 2 barrels start siphoning gas out of the pump discharge nozzle at high rpm. it causes an extremely rich condition up top. if you use the 4412 - buy the new metering block from holley. it helps these problems a lot. it costs around 100 bucks. if not try the stock weber 32/36. it flows around 300 cfm which according to my calculations and those you find on this website will feed your 140 cubic inch motor to well beyond 8000 rpm.

way2fast
Dirt Maniac

Total posts: 104
posted September 30, 2003 12:09 AM  
where would I find this weber carb? and are there any adapters need,etc? thanks

b4racing
Dirt Forum Champ
Total posts: 626
posted September 30, 2003 12:25 AM  
I think you would need to look at the 70's 4 cyl. or do like me and find them on ebay a lot easier. Bobby

way2fast
Dirt Maniac

Total posts: 104
posted September 30, 2003 12:35 AM  
So this carb was available on a ford 4 cyl? also, where do you find all these parts on e-bay, do you search for them? if so, what section? thanks

USAUS Racing
Dirt Full Roller

Total posts: 69
posted September 30, 2003 08:44 AM  
New 32/36 webers can be had from Victoria British Motors (1-800-255-0088) and Moss Motors (1-800-667=7872) and a Weber 38/38 can be had from Brit-Tek (1-800-255-5883). All of these places stock them for use on MGB sportcars. Manifolds are another question and you might have to make your own adaptor.

NH RACER
Dirt Roller

Total posts: 8
posted September 30, 2003 10:00 AM  
http://www.webercarbsdirect.com/home

b4racing
Dirt Forum Champ
Total posts: 626
posted September 30, 2003 10:58 AM  
just type in weber as the search word and ebay and you will see a ton of stuff. I bought a new 38/38 off of there for about 100 less than other places quoted me. Bobby

speedyd1
Dirt Maniac

Total posts: 170
posted September 30, 2003 01:01 PM  
most if not all the pintos and early model mustangs with carburetors came with webers or the holley built "weber" 5200. they are great little carbs and meet the stock requirements at most tracks.
webercarbsdirect.com is a good site.
you can expect them to be about 250 ea.
the 38 mm DGAS Weber flows about 490 cfm and is a great upgrade instead of the holley 500. if you get a used one - have it rebuilt by a competent carb guy in your area. carbs dont do very well after having sit for 20 years. you can find them on ebay by typing 32/36 and doing a search. ive payed as little as 10 bucks each before.

Adams64
Dirt Roller

Total posts: 10
posted October 05, 2003 09:35 PM  
you guys ever run the 2 barrels off the ford v-8's that's what i run and it works great

way2fast72
Dirt Freak

Total posts: 303
posted October 05, 2003 10:26 PM  
Thats what we run now, just thought the Holley may be better.

Adams64
Dirt Roller

Total posts: 10
posted October 05, 2003 10:33 PM  
i'd go holley i think the advantages outweigh the disadvantages i don't think switching to one of the webers is gonna benifit you anyway

way2fast72
Dirt Freak

Total posts: 303
posted October 06, 2003 12:45 AM  
Any Idea where a good starting point is for jet size?

KPLugnut
Dirt Forum Champ
Total posts: 1019
posted October 06, 2003 08:05 AM  
No way to accurately answer without knowing your air quality/density, full engine specs, compression ratio, and how the whole rest of the carb is set up.
For box stock 412 2bbls on ministocks, generally, a 64-68 jet will at least allow it to run.
But keep in mind, the 500cfm Holley is too large a carb for the typical ministock motor unless you're turning 8000rpm or more and are heavily modified. So to get that carb to run right on a mini, it always has to be "detuned" in many areas. This does NOT just involve putting in extra small jets...

JMHO..

Kinetic Performance

USAUS Racing
Dirt Full Roller

Total posts: 69
posted October 06, 2003 08:40 AM  
for a 350 try #68 main and #35 power. A 500 uses #70 main adn #35 power. Holley also have an off-road kit that helps too.

way2fast72
Dirt Freak

Total posts: 303
posted October 07, 2003 03:28 AM  
thanks everyone who replyed, we are going to go ahead and give it a shot, just see how it turns out!

speedyd1
Dirt Maniac

Total posts: 170
posted October 07, 2003 10:56 AM  
and just a little after thought for you guys who dont know - the weber is fully adjustable from top to bottom. the holley of course is not. not to mention the fact that all high performance cars from europe use the weber series of carburetors just for that reason. can you say ferrari, lamborghini, mazzorrati, etc. i'll send more info if you need proof.

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