Swapping out OEM distributor with HEI distributor

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boloboss

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Well guys that's what I have a stock 350. So from all the info this tells me that the engine had to be swapped before I got it from a 305 because it had that type of distributor with the ESC)
 

Bextreme04

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I disagree but,don't want to argue about.
What part do you disagree with? GM never equipped a 350 with ESC until it went to TBI as far as I know. The curve on that distributor would not be correct for that engine(assuming that he ACTUALLY does have a 350).
Well guys that's what I have a stock 350. So from all the info this tells me that the engine had to be swapped before I got it from a 305 because it had that type of distributor with the ESC)
How do you know you actually have a 350? Did you run the block casting number and engine stamping number to know what the actual engine is?
 

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I disagree but,don't want to argue about.
Well then explain rather than argue.
ESC when working right on the RIGHT engine, ie a stock 305, is great, almost necessary.
What the OP has does it appear to even remotely be a stock 305.
And OP, your original distributor is/was also HEI. (Not points or some other aftermarket distributor style)
 

Rustisbest

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Can you send all that stuff to me? I want to be the first to do an "ESC swap"
 

Ricko1966

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Driving. I'll explain on little bit.
 

85K304SPD

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Only if he still had a stock 305. AFAIK the 350 never has ESC, it was only a stopgap for the piss poor head design of the 305 that made them an absolute dog with the small amount of timing you would need to set for it to not knock. If the engine has been replaced for a reasonably worked over 350, the ESC and 305 spark curve would be absolutely terrible on it.
Are you sure that only the 305 came with the electronic HEI? Both my Big block truck and my 350 small block truck have those wiring harnesses hanging there doing nothing.
 

Ricko1966

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Okay,home now. 305s didn't get esc because of a crappy head design etc. They got esc when they upped the compression,about 1981 and they needed to run premium or they'd ping. The answer was knock sensor,pull timing as needed.. Some 350s had esc by 83, all of them had it 1987 on. Vortec engines with the heads everyone raves about has esc,lt1s which have great heads have esc,LSs with even better heads,have knock control. Here's the simple version let's say your car could use 54* at lean cruise on the highway and get it's best gas milage and it could use 12 initial for best acceleration,but you've got a little ping down low and going uphill,so your only running 10 initial,you've got a ping at part throttle on the highway so you put in an adjustable vacuum advance and pull out 4 degrees. Let's do the math you've pulled 6 degrees of timing,to cure a ping that only sometimes happens. When do you get that 6*back? Never! Okay with knock sensor it's going to pull 4 degrees,only when it senses ping. Okay 4 wasn't enough,it's going to pull another 4. Guess what? You are getting back,your 8 degrees when the detonation goes away. Everything Vettes,Impala SSs ,GTOs got spark control so they can make the most power and not detonate. Some of you turn your timing back and forth,depending on whether you are running premium,no need with knock sensor,good fuel it's not going to pull timing,crappy fuel it will pull timing when it needs to.We don't have a lot to work with,with a factory HEI ,we can change springs,initial and vacuum advance cans. Why give up another tool you have to tailor the ignition? Yea people are going to say mine failed and left me stranded,okay,it's like lots of parts,yea,lots will leave you stranded. So what, it takes 2 minutes to bypass it if necessary to get you home and fix it. You can't do that with an Automatic transmission, it could leave you stranded. So let's all get manuals just so we don't get stuck. Hmm manuals fail to don't they? So do regular HEIs and they leave you stranded. I'm not saying a factory knock sensor HEI has the ideal curve for your hot rod,but it can be recurved just like any other HEI and give you the advantage of being able to run the timing you want,without compromising. IDK if @Rustisbest is being sarcastic about wanting O.Ps knock sensor stuff,but I grab all I can when the price is right.
Seriously, what does everybody do if they have detonation? Pull timing,but manually pulling it,you never get it back. Your timing is set permanently to less than ideal,to avoid temporary preignition.
 
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TotalyHucked

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I get what you're saying, adjustable timing is a huge benefit, but that factory '80s ESC system has never worked well even when new. Let alone 40yrs later when the replacement parts are getting harder and harder to get. My truck ran muchhhh better after we deleted the ESC. Set the timing at a safe point, get fuel from quality stations and just pay attention to your engine. It'll let you know if it's rattling (feel and/or sound) and unhappy.
 

Rustisbest

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Yes... I was being sarcastic lol. If it's detonating you have the wrong timing in it, especially if it's 4, 6 or 8 degrees too much. When do you get the power back from it detonating because you have it wrong? Common sense says adjust the curve instead of putting a bandaid on it.
 

Ricko1966

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Yep that's why all manufacturers even the foreign stuff went to knock sensor ignition,because knock sensors suck. It's not a bandaid it's a tuning tool that's why they are still using them. Set the timing right,hmm well that changes daily with altitude,temperature,fuel quality,humidity and what kind of load you have. The knock sensor adapts. The factory esc stuff worked fine,still does,lots of people,have deleted their esc,and then switched back. I think the ones that deleted and were happy afterwards were happy because they never drove it when it was working right.
 
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CountKrunk

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Just did a quick google and apparently almost every modern car has them today. Including my 2016 camry.

And apparently modern cars have 70 or more sensors related to performance lol
 

Rustisbest

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They went to EFI and coil near plug too. That ain't got jack **** to do with a 40 year old truck with a carb on it though.
 

Turbo4whl

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Can you send all that stuff to me? I want to be the first to do an "ESC swap"
You won't be the first to put ESC on an engine that never had it.

You should re-read Rick's post #22. Like anything new, the early systems were not perfect, but the concept was great.
 

Ricko1966

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I get what you're saying, adjustable timing is a huge benefit, but that factory '80s ESC system has never worked well even when new. Let alone 40yrs later when the replacement parts are getting harder and harder to get. My truck ran muchhhh better after we deleted the ESC. Set the timing at a safe point, get fuel from quality stations and just pay attention to your engine. It'll let you know if it's rattling (feel and/or sound) and unhappy.
My truck the ESC went down . I put in a regular HEI I messed with it springs,weights,vacuum can initial. I never got it to run as a total package as well as it did with ESC. Same with @SirRobyn0 he chronicles all the changes he made over the coarse of a year,finally when it was all said and done,it was back as an ESC truck. He documented it all recorded gas milage etc. I can tell you mine runs better with esc. But I didn't document anything. Working ESC is best in my truck. I suspect yours never worked right. So it's real similiar to the I took off a messed up Qjet and put on an Edelbrock and it runs great stories. But you never hear anybody say I compared a Fresh Quadrajet to an Edelbrock.
 
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Ricko1966

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They went to EFI and coil near plug too. That ain't got jack **** to do with a 40 year old truck with a carb on it though.
Sure it does. I can set my timing where the truck runs good on a 50 degree day with no load or 90 degree day pulling a trailer. Because timing demands change,and esc adapts.GM designed it and installed it for a reason. Yes even 350s started getting ESC 1983 ish. Small blocks didn't used to have HEI at all,but people upgrade to it. I consider knock sensor an upgrade. So did GM.
 
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