1983 C10 383 Stroker dies after a lil cruisin

[C10SLEY]

Hello,

Let me start by saying I'm new to this forum, but not forums. So I know I should ask for forgiveness before posting about something someone else might say, "do you research before asking these questions", and I have already done my research and read similar, but not identical, posts regarding my situation, plus most of the threads are over 10 years old, and y'all have learned more since then. There.
So, I recently inherited my late brothers 1983 C10 383 stroker. He passed away right at 6 years ago, and the truck has been sitting in a garage ever since. I've played with Subarus for a dozen years, and don't know much about muscle (that was my brothers thing), but now I'm learning! I dug the truck out, sent it over to my sister's shop, and got some gaskets replaced, and the Holly 850 double pumper rebuilt by "Pops" (an old timer I've known my whole life [30 yrs] that knows what he's doing).
Here's what's happening: crank truck with full choke, *boom* fires right up and runs great, push choke back in, "let's go for a drive", drive, smooth, ~5-10 mins later, struggles to run a little, and if no throttle is given (maybe going downhill or in a curve or at a red light), it dies. Hold pedal to the metal, crank, crank, crank, *boom* fires up and drives smooth again for a bit, then the same thing happens all over again. It seems as though if I'm not giving it the onions, it gives up. Also, my dad says it smells like "it's loading up" once it's warm and idling. Lastly, it idles a little high once warm.
I don't have temps, RPM info, oil press, etc rn. The truck is 4 hours away. I'm in grad school. I go home and fiddle with it occasionally (more, recently).
If you read all that, congrats; I just want to preface the whole situation so I can get a more detailed response.
Thank you all!
Caleb T.

 

[SirRobyn0]

@C10SLEY I think you'll find this forum to be a little different from all others. For example it is highly unlikely someone will tell you to search for information because our search function is not that great, though I do think it's improved some since our "upgrade". In general most of us see this place like a community, I didn't understand that the first time someone said that to me when I had just signed up but now I do, I get it. You will to if you hang around enough.

With the info you have given I can only see two likely possibilities. Something over looked or done wrong during the carb rebuild, now I'm not trying to say anything bad about "pops", I've rebuilt many a carb and work in a shop too, but that doesn't make us infallible. We can still make a mistake or flat out get a bad part. To high of fuel pressure pushing fuel past the needle and seat and into the float bowl.

BTW, your post is not to long at all. Good detailed descriptions, give us guys more info to form possible answers for you.

 

[C10SLEY]

@C10SLEY I think you'll find this forum to be a little different from all others. For example it is highly unlikely someone will tell you to search for information because our search function is not that great, though I do think it's improved some since our "upgrade". In general most of us see this place like a community, I didn't understand that the first time someone said that to me when I had just signed up but now I do, I get it. You will to if you hang around enough.

With the info you have given I can only see two likely possibilities. Something over looked or done wrong during the carb rebuild, now I'm not trying to say anything bad about "pops", I've rebuilt many a carb and work in a shop too, but that doesn't make us infallible. We can still make a mistake or flat out get a bad part. To high of fuel pressure pushing fuel past the needle and seat and into the float bowl.

BTW, your post is not to long at all. Good detailed descriptions, give us guys more info to form possible answers for you.

Thanks for the support!! I'm looking forward to being a part of that community.
I like only having two possibilities, lol. It could very well be that Pops screwed something up. I know almost nothing about carbs, so tuning it myself without first watching 2-10 YouTube videos is not happening. But we'll work it out. As for the fuel pressure, it has a Edelbrock (Victor or RPM Series) fuel pump. Can't I hook up a pressure gauge in series with the fuel lines and measure the pressure without having an installed fuel pressure gauge?

 

[SirRobyn0]

Thanks for the support!! I'm looking forward to being a part of that community.
I like only having two possibilities, lol. It could very well be that Pops screwed something up. I know almost nothing about carbs, so tuning it myself without first watching 2-10 YouTube videos is not happening. But we'll work it out. As for the fuel pressure, it has a Edelbrock (Victor or RPM Series) fuel pump. Can't I hook up a pressure gauge in series with the fuel lines and measure the pressure without having an installed fuel pressure gauge?

Well that's a good quality pump unlikely to cause excessive fuel pressure so I'd be looking at the carb. If you were closer to the truck I'd ask you to do a video of it running and acting up. I really think it's in the carb though. Does it have an egr valve? Sometimes a bad egr valve will cause so much vac loss that the carb will stay in enrichment mode. I'm just throwing out ideas I still think it's in the carb

 

[C10SLEY]

Well that's a good quality pump unlikely to cause excessive fuel pressure so I'd be looking at the carb. If you were closer to the truck I'd ask you to do a video of it running and acting up. I really think it's in the carb though. Does it have an egr valve? Sometimes a bad egr valve will cause so much vac loss that the carb will stay in enrichment mode. I'm just throwing out ideas I still think it's in the carb

Not sure if it has an EGR valve, but I'll look into that. Dad seems to think it has to be the carb as well. He said, and another guy at the shop, that the 850 is just too big, and maybe just giving it too much fuel. Based on the research I've done, about any carb can be tuned to fit the 350/383 stoker, but ideally you wouldn't put such a big carb on a small block. I will be home for several days for Christmas and will check more things out and will also have talked to the previous owner and learned a lot more and get back to you and this thread.

 

[SirRobyn0]

Not sure if it has an EGR valve, but I'll look into that. Dad seems to think it has to be the carb as well. He said, and another guy at the shop, that the 850 is just too big, and maybe just giving it too much fuel. Based on the research I've done, about any carb can be tuned to fit the 350/383 stoker, but ideally you wouldn't put such a big carb on a small block. I will be home for several days for Christmas and will check more things out and will also have talked to the previous owner and learned a lot more and get back to you and this thread.

That's true that carb is to big, but typically to big of a will result in issues when your hammering down. Now if it's got to big of jets on the secondaries plus being over sized it might be possible to end up with gas pooling on the manifold then you shut the throttle and high vacuum sucks all that raw gas into cylinders and kills it. That's one thought anyway. When your home for Christmas if you get the chance do a little video of the truck acting up and post it up in this thread and I'll give you my thoughts on what I see and hear.

 

[C10SLEY]

That's true that carb is to big, but typically to big of a will result in issues when your hammering down. Now if it's got to big of jets on the secondaries plus being over sized it might be possible to end up with gas pooling on the manifold then you shut the throttle and high vacuum sucks all that raw gas into cylinders and kills it. That's one thought anyway. When your home for Christmas if you get the chance do a little video of the truck acting up and post it up in this thread and I'll give you my thoughts on what I see and hear.

I will do this. Great advice, and thanks for all the tips!

 

[C10SLEY]

Following up this thread to say that after replacing the Holly 750 double pumper with a Quick Fuel 580 CFM HR-series, the truck is running so good! Now on to other things

 

[WP29P4A]

I was thinking the carb seemed a bit big for that engine. I have a stroked 500ci big block and the 800cfm carb is a little over kill for my engine.

 

[NastyRay]

Hello,

Let me start by saying I'm new to this forum, but not forums. So I know I should ask for forgiveness before posting about something someone else might say, "do you research before asking these questions", and I have already done my research and read similar, but not identical, posts regarding my situation, plus most of the threads are over 10 years old, and y'all have learned more since then. There.
So, I recently inherited my late brothers 1983 C10 383 stroker. He passed away right at 6 years ago, and the truck has been sitting in a garage ever since. I've played with Subarus for a dozen years, and don't know much about muscle (that was my brothers thing), but now I'm learning! I dug the truck out, sent it over to my sister's shop, and got some gaskets replaced, and the Holly 850 double pumper rebuilt by "Pops" (an old timer I've known my whole life [30 yrs] that knows what he's doing).
Here's what's happening: crank truck with full choke, *boom* fires right up and runs great, push choke back in, "let's go for a drive", drive, smooth, ~5-10 mins later, struggles to run a little, and if no throttle is given (maybe going downhill or in a curve or at a red light), it dies. Hold pedal to the metal, crank, crank, crank, *boom* fires up and drives smooth again for a bit, then the same thing happens all over again. It seems as though if I'm not giving it the onions, it gives up. Also, my dad says it smells like "it's loading up" once it's warm and idling. Lastly, it idles a little high once warm.
I don't have temps, RPM info, oil press, etc rn. The truck is 4 hours away. I'm in grad school. I go home and fiddle with it occasionally (more, recently).
If you read all that, congrats; I just want to preface the whole situation so I can get a more detailed response.
Thank you all!
Caleb T.

Something you might wanna check is where the carb meets the intake if it is warped or not sealed right any bit of air in there will cause what you are explaining

 

[SirRobyn0]

Following up this thread to say that after replacing the Holly 750 double pumper with a Quick Fuel 590 CFM HR-series, the truck is running so good! Now on to other things

I was thinking the carb seemed a bit big for that engine. I have a stroked 500ci big block and the 800cfm carb is a little over kill for my engine.

I agree, I think a lot of guys over carburate, I think part of the problem is it feels like to me carb companies often make it sound like more is better and that's just not the case. Also guys look at the CFM rating of the Q-jet not realizing it's a maximum CFM and the Q-jet will only give what's needed. I'm in the same boat, the PO over carbureted my 305 with a 650, edelbrock it ran terrible when you'd get into it, but lucky he bought the older version of the AVS called the thunder and you can manually adjust the secondary air valve effectively limiting CFM.