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Summit 600cfm 4v

4K views 18 replies 5 participants last post by  greazyball 
#1 ·
I have finally had a chance to run my WILLYS truck around and begin fine tuning everything.I installed a brand new summit 600cfm 4V carburetor.A very simple carb like the Autolite 4100.I LOVE this carb!! its working flawlessly and EASY to adjust and while it will be awhile to see if its reliable and STAYS adjusted..im getting clean exhaust doesnt seem to be running rich.And im getting a solid 22mpg at 60mph..its a stock 1979 Ford 302/FMX ,Pertronix Ignitor,shorty headers,duals with glasspacks out the back.The rear axle gears ratio is 3.08..the tag indicates its supposed to be 2.79,But a quick check its actually 3.08.Anyways solid carb,simple,easy to adjust and it was just shy of $260.00 delivered to my door.Its not a Holley,which for me is a blessing.
 
#3 ·
summt 4v

From what i can learn the summit 4v is based on the holley 4010..why Holley abandoned it,i dont know except the people who bought it,Sais those 4010's sucked.I took apart my summit when i got it,And i also borrowed a friends 4010.they appear similar,However i also took apart one of my autolite 4100's.And the summit is alot closer to a 4100 than the holley is.Like you i can only wish that somebody would reproduce the Autolite 4100..Pony carbs has remanufactured 4100's at near $500!! sorry but i wont EVER pay that for an autolite.In my opinion,the summit is about as close as any of us Ford guys will get to a 'new' autolite.The summit does use holley parts,One thing that will NEVER happen and that pissed me off royally was if i was running a holley..if the engine so much as coughed or sputtred it would blow a power valve and dumped raw fuel into the engine.I think i made a good choice..i didnt like the idea of an Edelbrock,another holley,Demon etc..they all have too many moving parts in my opinion.The autolite was reliable because it was simple..and the summit is also simple
 
#5 ·
been driving the truck for awhile now,I just adjusted the floats and jets for the first time.I really really really like this carb,I just pegged the mileage at 19.5mpg and thats at 65mph and alot of in town driving added.If its all in town it drops to about 15mpg or less.So im quite happy with the carburetor.throttle response is immediate,the acceleration is smooth.It really behaves as an Autolite 4100.im buying another one for the 1965 falcon wagon im doing for my daughter,And then i talked my son into buying one for his 72 maverick 302/C4.
 
#7 ·
i think im going to stick with the summit i bought,its simple and so far has been reliable,time will tell.its similar to the Autolite 4100 which i love,but the cores i have do not warrant rebuilds..not when there are the summits available.Besides the truck is a daily driver and i want to save the autolites for a car thats more for recreation and wont be driven everyday...and also i want to keep them out of circulation so PONY CARBS cant get them and charge $500 for a carburetor hahaha
 
#8 ·
i wish i would have purchased that too, instead of the edelJUNK carb that i got for about $160 from summit too. am about to put my old holley 600 back on. what a P.O.S.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! (SEE my product review of same).
 
#9 ·
my brother wont run anything but an edelbrock 4bbl,I dont know why..but he can keep it tuned,running nicely,i tried one but i couldnt get it to tune...its too much like a 'quadraHOG.he hates the autolites,motorcrafts.But for some odd reason he loves that edelbrock and quadrajets...holleys are a close 2nd. yuukkk!! i will take this summit any day over those things
 
#10 ·
The Summit carb has several improvements that make it more tunable- like a separate replaceable accelerator pump shooter and removable bleeds. The Holley version had no way of changing the shooter size except to drill them out or replace the entire cluster at about $25 a pop (1992 price).

The Summit also has all the secondary vacuum cover screws accessible; the Holley had one screw hidden, making it harder than it should be to work w/the vacuum secondary spring, check ball, or diaphragm.
 
#11 ·
i like the summit because it behaves likes an autolite 4100,but has some improvements..i do like being able to adjust my floats without having to remove the top of the carb,i like the windows so you can see your fuel level,i do like that it uses holley parts..i know i say i dont like holley carbs...in general i do nor,But they do make excellent parts and pieces that are in this summit
 
#12 ·
I have encountered my first trouble with this summit four barrel.the power vlave or accelerator pump has failed..i think.I noticed the truck was running very rich and then my mileage dropped to 10-12mpg i was getting a good 15-18.Im looking for a rebuild kit but it appears that the rubber diaphrams are not part of the kit..dammit! years ago when you got a rebuild kit..you got EVERYTHING that was a 'moving part'. I dont want to rebuild the entire carburetor it only has 6 or 7 thousand miles on it.I was told that these summit carbs use 'Holley' parts.Is this true? And i also would like to jet down a hair if i could.
 
#13 ·
Replace the power valve w/a Holley part. A '65' is the 'go-to' size for mild engines, if you have a big cam you may need to go to a smaller number so the enrichment doesn't come in too soon. Details of the engine and vehicle will help here.

The accelerator pump won't make it run rich. As long as you're getting a good stream from the shooters at the hit of the throttle and you have a tiny bit of free play at WOT the accelerator pump adjustment is OK. It might need a bit of tuning if you're looking for the best possible mileage, though.

BTW, you can use Holley jets, too.;)
 
#16 ·
Cool! holley jets too? I love this carburetor but its a tad too much fuel for a stock 302 i was hoping to maybe jet down a hair so the fuel/air burns a little cleaner.I know 600cfm is considered 'small' but my autolites were only 450cfm and 480cfm 4bbl carbs..and on stock 289/302 i was getting 21-23mpg..i dont dare think i can get it with this carb.But i would like to lean it a bit
 
#18 ·
HAWT DAWG! i love this carburetor! the power valve was broken,But i went and picked up a Holley 6.5,pulled the carburetor screwed in the new valve,Bolted everything again and i just got back from a ride and adjusting the carb.I think the power valve might have been broken for awhile and maybe it just got worse the last several days.Because the truck runs much smoother and throttle response is quick and sharp.the rich smell and eyes stinging are gone
 
#19 ·
DONE! i didnt have a bad power valve (but i put a holley 65 in it anyways) and i didnt have a bad accelerator pump (my 2nd guess) i took the carb apart today cleaned it with carb/choke cleaner and you were right,The check ball had some crud around it,And i found some filings in both bowls.Im guessing its from when the carb was assembled at the factory (yes,i know i should have checked before i installed it) I also found a vacumn leak on one the rubber caps i used on the intake.I put it all back together with a new fuel filter.warmed the truck up then began tuning it.The nostril stinging smell of raw fuel is gone,the sputter from a vacumn leak is gone.the electric choke works yeah thats a '1st' for me,if i ever had a carb with an electric choke i usually broke it off and modify for a manual choke.Some final checks and small adjustments and then i will be done.this carb has been minimal headaches..the flooding issue was my own fault.i have been driving the truck because i needed it badly...i never wired the electric choke to run as designed i just twisted the round thingy til the carb was all the way open so it would run til i could wire it up..bad idea.but its alright now
 
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