Summit Carb Install Gone Very Wrong

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nabeshin

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More than likely. I've generally been happy with Summit-branded stuff. The headers I've got on my truck now are theirs and I'll be honest - they are sweet.



I'm thinking this is 99% of the problem right here. Too bad too because it is a nice looking carb. I just wish I could have afforded the more expensive US-made brands. I had to do something though. I've had it up to here with the Q-jet. I just can't get it right and it hates the (relative) cold weather we've had here in FL recently. So F it.

My truck is basically stock, with Quadrajet, exhaust heat riser, and thermostatic blend door on the snorkel air box. Started up almost instantly when it was negative 25 F outside, same temp in the barn. Ran just fine.
 

80BrownK10

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I live in the south too. We don't have bitter cold. But I can start my truck with the QJ into our coldest temps in the 20s. It will start up pretty quick and then die out of ter a few seconds. Hot the petal on e or twice and then it will crank up and run at high idle till I knock it off.
 

80BrownK10

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Mine has 2 springs, one inside the other. Theyre stiff enough when cruisin i can let off the gas and tap my foot on the pedal with the beat of a song. Stiffer keeps me from tryin to burn out lol. When i got my s10 i had a hell of a time adjusting to the pedal! A 2wd with a 4.3L and a soft pedal... i still unintentionally lay rubber at a stop sign or light.
2 work trucks ago I had I think it was an 07 Dakota with the v8. It was 4wd but driving around especially on wet pavement I hit the petal hard it would roast the tires and slide out sideways.
 

SirRobyn0

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Mine has 2 springs, one inside the other. Theyre stiff enough when cruisin i can let off the gas and tap my foot on the pedal with the beat of a song. Stiffer keeps me from tryin to burn out lol. When i got my s10 i had a hell of a time adjusting to the pedal! A 2wd with a 4.3L and a soft pedal... i still unintentionally lay rubber at a stop sign or light.

Sounds about how I like mine.

My truck is basically stock, with Quadrajet, exhaust heat riser, and thermostatic blend door on the snorkel air box. Started up almost instantly when it was negative 25 F outside, same temp in the barn. Ran just fine.

I talk about this all the time and how those three things, the choke, heat riser, and thermostatic door aka thermac work together. Can a person run a vehicle without them sure, but those systems came factory to help with cold drivability and to warm the engine up a little faster for efficiency. I'm a one pump guy, I want my truck to fire with one pump, run and be able to drive off within a few seconds without any drama, which my truck does do.
 

da_raabi

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When I first got this truck years ago it ran great on the stock carb. It looked like it had never been touched. Unfortunately the ethanol in newer gas started to do it's thing and a rebuild was in order. I don't know why, but its never been the same since. It runs decent, but it can be rough to start in the cold (all equipment mentioned above was removed prior to my ownership) and it hesitates when you punch it. I dunno. I figured I'd try something a little different and so far I'm happy with the decision. I'll probably do the same thing on my Camaro when I finish the engine build. I planned to use another Quad I had, but at this point I think this is the better route.

Don't beat yourself up on this. If there is something you missed and it cracked oh well, it might be a rather expensive mistake but it happens, believe me, I'm a careful mechanic to, and things break. I think thermostat housings are the most popular thing to break, but carbs happen to. Yes it could have been a bad casting. When you start changing throttle return springs just remember that having the throttle stick open because of to light of a spring really sucks. Conversely really stiff springs are hard on the throttle plate bushings over long periods of time.

Yeah I'm having some trouble with this right now. I had to use a custom throttle bracket to clear the carb, and using the two springs included resulted in a STUUUUUPID hard pedal. Like my foot was starting to hurt after about 2 minutes. WOT was almost impossible. One spring is better, but now I'm having trouble with it not wanting to fully return to idle. Bopping the throttle helps, but it's very annoying sitting at a stop light with it revved to 1200rpm. My next guess is the throttle cable itself as it appears to be too long. I'm still using the stock one, and you can see in the pic it had to do a big loop. Probably not great. The cable is newer (2-5 years old maybe?) so it should be fine condition wise. I just think its too long. So a custom one is likely in order.

It is a good lookin carb! And holy crap!, i havent seen you around in a bit!!

Yeah I've been off the site for a while. I've been spending more time over at NastyZ28 because I'm working on building up a carbed LT1 for my 80 Camaro. I'll try to not be such a stranger :)


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SirRobyn0

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Don't beat yourself up on this. If there is something you missed and it cracked oh well, it might be a rather expensive mistake but it happens, believe me, I'm a careful mechanic to, and things break. I think thermostat housings are the most popular thing to break, but carbs happen to. Yes it could have been a bad casting. When you start changing throttle return springs just remember that having the throttle stick open because of to light of a spring really sucks. Conversely really stiff springs are hard on the throttle plate bushings over long periods of time.

When I first got this truck years ago it ran great on the stock carb. It looked like it had never been touched. Unfortunately the ethanol in newer gas started to do it's thing and a rebuild was in order. I don't know why, but its never been the same since. It runs decent, but it can be rough to start in the cold (all equipment mentioned above was removed prior to my ownership) and it hesitates when you punch it. I dunno. I figured I'd try something a little different and so far I'm happy with the decision. I'll probably do the same thing on my Camaro when I finish the engine build. I planned to use another Quad I had, but at this point I think this is the better route.



Yeah I'm having some trouble with this right now. I had to use a custom throttle bracket to clear the carb, and using the two springs included resulted in a STUUUUUPID hard pedal. Like my foot was starting to hurt after about 2 minutes. WOT was almost impossible. One spring is better, but now I'm having trouble with it not wanting to fully return to idle. Bopping the throttle helps, but it's very annoying sitting at a stop light with it revved to 1200rpm. My next guess is the throttle cable itself as it appears to be too long. I'm still using the stock one, and you can see in the pic it had to do a big loop. Probably not great. The cable is newer (2-5 years old maybe?) so it should be fine condition wise. I just think its too long. So a custom one is likely in order.



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First about the throttle, if it's not fully returning this can be dangerous if it decided to stick open wider than it already is. Make sure that the cable is straight on with the carb, if it's off at an angle it can cause it to bind. Then check to make sure the cable is free and don't overlook the pedal. I once had an old rig at the shop with throttle return issues and it turned out to be the hinge on the pedal being a bit rusty and to stiff.

Keep in mind that carb was 30 years old when it gave up on you might have just been it's time.
 

80BrownK10

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First about the throttle, if it's not fully returning this can be dangerous if it decided to stick open wider than it already is. Make sure that the cable is straight on with the carb, if it's off at an angle it can cause it to bind. Then check to make sure the cable is free and don't overlook the pedal. I once had an old rig at the shop with throttle return issues and it turned out to be the hinge on the pedal being a bit rusty and to stiff.

Keep in mind that carb was 30 years old when it gave up on you might have just been it's time.
I had a throttle stick on me on the square. I was going into a pretty good curve in the highway. I throw it in neutral and cut the engine off coasted off to the side and drove the few miles back home. Then took my other truck to town and also picked up a throttle cable .
 

80BrownK10

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When I first got this truck years ago it ran great on the stock carb. It looked like it had never been touched. Unfortunately the ethanol in newer gas started to do it's thing and a rebuild was in order. I don't know why, but its never been the same since. It runs decent, but it can be rough to start in the cold (all equipment mentioned above was removed prior to my ownership) and it hesitates when you punch it. I dunno. I figured I'd try something a little different and so far I'm happy with the decision. I'll probably do the same thing on my Camaro when I finish the engine build. I planned to use another Quad I had, but at this point I think this is the better route.



Yeah I'm having some trouble with this right now. I had to use a custom throttle bracket to clear the carb, and using the two springs included resulted in a STUUUUUPID hard pedal. Like my foot was starting to hurt after about 2 minutes. WOT was almost impossible. One spring is better, but now I'm having trouble with it not wanting to fully return to idle. Bopping the throttle helps, but it's very annoying sitting at a stop light with it revved to 1200rpm. My next guess is the throttle cable itself as it appears to be too long. I'm still using the stock one, and you can see in the pic it had to do a big loop. Probably not great. The cable is newer (2-5 years old maybe?) so it should be fine condition wise. I just think its too long. So a custom one is likely in order.



Yeah I've been off the site for a while. I've been spending more time over at NastyZ28 because I'm working on building up a carbed LT1 for my 80 Camaro. I'll try to not be such a stranger :)


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That stupid long hose clamp on the upper rad hose would drive me crazy. I'd have to replace it or more likely cut it to size.


And are you really a Rabbi?
 
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da_raabi

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That stupid long hole clamp on the upper rad hose would drive me crazy. I'd have to replace it or more likely cut it to size.


And are you really a Rabbi?

Ha! I wondered if someone would catch that clamp. It's all I had when I did the hose and then I just forgot about it. Too funny man.

And no, I'm not a Rabbi or even of that faith. It's actually a nickname I picked up as a kid. It's a twist on my name is all.
 

78C10BigTen

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Ha! I wondered if someone would catch that clamp. It's all I had when I did the hose and then I just forgot about it. Too funny man.

And no, I'm not a Rabbi or even of that faith. It's actually a nickname I picked up as a kid. It's a twist on my name is all.
I was wondering if youre the trailer park supervisor mr. Lahey lol
 

80BrownK10

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Ha! I wondered if someone would catch that clamp. It's all I had when I did the hose and then I just forgot about it. Too funny man.

And no, I'm not a Rabbi or even of that faith. It's actually a nickname I picked up as a kid. It's a twist on my name is all.
Yea I figured that it was all you had laying around at the time. For me it's an hour round trip to town, so I totally would do the same thing.
 

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