• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

I need some carb therapy... 69 GTX

Lineman

Well-Known Member
Local time
5:53 AM
Joined
Jun 24, 2017
Messages
145
Reaction score
30
Location
Glen Burnie, MD
I have been chipping away at trying making this GTX a nice driver/working out some of the bugs the previous folks and father time have left this car with.. This is a real GTX and I have some documentation of history but no build sheet or fender tag. Although I can track past owners, i think.

Original engine and trans is long gone, or when I get time that is another whole avenue to investigate.. For now though originality is purely a cosmetic thing. I will attach the Holley carb pic I am taking off that has no choke horn at all. I guess a Elderbrock would look the most correct if I could get the sticker off? I have been trying to fool with Holleys and i have ok luck with them but they have their issues as a driver carb for me..

Hence my, question. Just how good are the Street Demons? They sound like pretty nice street carbs and people seem to like them? This is I have a struggle with keeping an originality look and using that carb?

Thanks for listening, Its cold out, the car needs a choke.. What are your thoughts??

Thanks

Jay

2022-01-13 12.51.38.jpg 2022-01-13 12.51.59.jpg GTX-3.jpg
 
Mine works good. Better than a plain Holley. That Holley looks like its straight off the Dirt track or the drag strip.

20211231_170015.jpg 20211231_170037.jpg
 
Mine works good. Better than a plain Holley. That Holley looks like its straight off the Dirt track or the drag strip.

View attachment 1225435 View attachment 1225436

Thanks, yeah that on my car is a standard Holley body without a choke horn and they must have thought they were real tuners.. So your carb I think is the next model up demon? The one I was thinking about tying is the square one. Maybe I should look into what you have going on there? I kinda like the AFB idea of the top opening up though and no float bowls.. I have been hearing good stuff in conversation in the threads about demons but I don't know which ones specifically..
 
This one is pretty old, so I dont know if they even still make them like this. Its just a 650 cfm. I like it because you can adjust all 4 corners on the idle mixture,instead of just 2 on the Holleys. I used to run an originalish Carter AVS and it worked fine on the original intake. Very similar to an Edelbrock.
 
My experience with my former '68 GTX, Baby Blue, may help, or just stir the pot. This car was pretty unique, in that it was almost completely stock, numbers matching, with the exception of the carb and fuel pump, from back in the 1970s. I owned it twice, 1983-91, and again 2013 until last year. When I owned the car the first time, it carried a warranty replacement Carter AVS which worked pretty well, but my friend who owned the car before me had tweaked the daylights out of it. Fast forward 30 years, the guy I sold the car to in 1991 replaced the AVS with a 770 cfm Holley Street Avenger. It was fed from a Holley electric fuel pump that my buddy had installed in the 1970s, still working great after all those years. Many of my Mopar buddies drove that car during the last eight years (including my buddy who tinkered with the AVS), and all agreed it was one of the best running Mopars they had ever encountered - good starts, hot or cold, no hesitation under any conditions, smooth idle. This is my only experience with a Holley, so it may be representative or not.

As far as the appearance of originality, the Holley used a spacer, and still had no clearance problems with the original factory air cleaner. I took the car to the Chrysler Nationals for years, and most people who looked under the hood never noticed the Holley.

440 GTX Engine.jpg
 
Why not use an AVS if looking for cosmetics?

You talking about finding an old Carter or an Elderbrock AVS2 I think I should probably at least have a 750cfm so I guess I have to go with the 800 Elderbrock if I go that way. Then to expand on that I have a smaller one of these on my pick up, driver and I like it and I there is an older one on the Roadrunner. I like them fine as drivers but I think they tend to be just that nice drivers. If it was a 1/4 mile car a Holley is hard to beat I think they just seem to be a good Et carb I think but tuning for tuning for the street.. I like the open top carbs I think. I have a 680cfm something or other Holley in the shop with electric choke I can try on the car and that fast idle I can get to better on that carb, just to see how it will act.. What a project over nothing.. I will say when I was racing I ran a vac. secondary 750 Holley and it was really good to me..
 
This one is pretty old, so I dont know if they even still make them like this. Its just a 650 cfm. I like it because you can adjust all 4 corners on the idle mixture,instead of just 2 on the Holleys. I used to run an originalish Carter AVS and it worked fine on the original intake. Very similar to an Edelbrock.

what exactly are you talking about there? Thanks
 
you can always go the route I did
850 cfm Thumper carb by Dominic Thumper
it has looks and performance
Dominic is an excellent tuner and lends his tuning expertise to all of his customers
He will custom build one for you according to your engine specifics
I was amazed at how close he got mine was almost perfect out of the box

IMG_20211226_143916681.jpg
 
you can always go the route I did
850 cfm Thumper carb by Dominic Thumper
it has looks and performance
Dominic is an excellent tuner and lends his tuning expertise to all of his customers
He will custom build one for you according to your engine specifics
I was amazed at how close he got mine was almost perfect out of the box

View attachment 1225530
I was just looking for his contact info.. I was going to get his take on it..

Thanks
 
Agreed. I'd vote for an AVS2. Stock appearing, cfm choices, manual or electric choke, easy to tune.
I had a 4640 on our 1985 360 B class camper van, way superior to the Q jet, which was a poor choice by Mopar. Still have the 4640. Ended up putting a TQ on it. Fantastic. Maybe a little off topic. Hope not.
 
Easy.... Get a new 3310 and pop that right in. (looks like you'll need a new fuel feed, you won't need the secondary metering block in your case) I'd done many in the past 50 years & all worked great, not only on Mopars but on brand x cars as well.
 
I spoke with Dominic, interesting guy.. Not exactly what I am after at this time though.. I think finally got the fast idle set on this one and it seems to be coming around like it wants to run pretty nice. This was 3310 was a manual choke and had been sitting for years, we have a shop in Baltimore that do a professional job at rebuilds and for $220.00 they rebuilt it and put an electric choke on it for me. I think I being an older style and/or a conversion to electric the fast idle screw was really hard to get to and I had to screw it just about all the way in. I was taking the carb off each time to adjust the damn thing.. I think I have it set just about right now. Things dry up around here from the snow and shitty weather I will get some time on it and will tell more but things are looking up.. As of now that old carb is in the swap meet bin.. I will see how this acts, thanks for the input. If I had to buy a new one I think it probably would be the AVS2.

2022-01-17 15.14.34.jpg
 
I spoke with Dominic, interesting guy.. Not exactly what I am after at this time though.. I think finally got the fast idle set on this one and it seems to be coming around like it wants to run pretty nice. This was 3310 was a manual choke and had been sitting for years, we have a shop in Baltimore that do a professional job at rebuilds and for $220.00 they rebuilt it and put an electric choke on it for me. I think I being an older style and/or a conversion to electric the fast idle screw was really hard to get to and I had to screw it just about all the way in. I was taking the carb off each time to adjust the damn thing.. I think I have it set just about right now. Things dry up around here from the snow and shitty weather I will get some time on it and will tell more but things are looking up.. As of now that old carb is in the swap meet bin.. I will see how this acts, thanks for the input. If I had to buy a new one I think it probably would be the AVS2.

View attachment 1225756
Please don't regard my comment as rude, but idle, fast idle, float level, idle mixture, etc. are all EASY screws to adjust on this carb.
 
Please don't regard my comment as rude, but idle, fast idle, float level, idle mixture, etc. are all EASY screws to adjust on this carb.

I appreciate your disclaimer, "but"...I think you are being RUDE.. So let me repeat and clarify. If the fast idle is so easy to get to on this carb why did I pull it off the car every time to adjust it?? The Holley carb sitting on my 360 the fast idle screw is no problem to get to so I agree.. on that carb.. On this carb I have been messing with.. For whatever reason, maybe because it was converted to an electric choke (as I stated earlier) or older or something its a real pain!!! I didn't enjoy pulling the carb to adjust it.. Also to get into the weeds, about Holley, if you want to change the jets, better be good with the cup to catch the gas... and getting the dual feed line off all the time etc.. and don't get me started on the power valve that I can skip.. I usually keep a pretty good running motor and I like a well tuned engine and its nice when they stay that way so when its set I think Holley is usually on the money and when I was racing the one I had then gave me some pretty constant ETs.. That being said I knew guys that knew every air passage, gasket, bushing in a carb and they would modify them for alcohol etc.. I was never that guy.. For the most part I know what I don't know..(how about you?) I know that fast the idle screw is a nuisance on this carb and its just about screwed all they way in.. I hope its not compensating for nothing more than the arm with the screw in it is from the manual set up. Next show I get to and there are a bunch of Holleys in front of me I will check them out better.. As always I appreciate help. Jay
 
I have been chipping away at trying making this GTX a nice driver/working out some of the bugs the previous folks and father time have left this car with.. This is a real GTX and I have some documentation of history but no build sheet or fender tag. Although I can track past owners, i think.

Original engine and trans is long gone, or when I get time that is another whole avenue to investigate.. For now though originality is purely a cosmetic thing. I will attach the Holley carb pic I am taking off that has no choke horn at all. I guess a Elderbrock would look the most correct if I could get the sticker off? I have been trying to fool with Holleys and i have ok luck with them but they have their issues as a driver carb for me..

Hence my, question. Just how good are the Street Demons? They sound like pretty nice street carbs and people seem to like them? This is I have a struggle with keeping an originality look and using that carb?

Thanks for listening, Its cold out, the car needs a choke.. What are your thoughts??

Thanks

Jay

Hey bro - you have the hood - match it up with the six pack carbs and manifold. I did that to my X decades ago and never looked back. Yeah I know there’s no such thing as a 6 pack GTX as far as originality goes but I think you state that you don’t so much care - and it gives the car some more moxie. A little difficult to tune and you have to play with them - but that’s half the fun. Make it a Stud!

Okay - my apologies - I just read the post above mine and can see a Six Pack is probably the farthest thing from what you want to do. I remember the Carter my 68 came with - what a mess that thing was. Good luck in your exploration. You’ll get it right.
 
Last edited:
I appreciate your disclaimer, "but"...I think you are being RUDE.. So let me repeat and clarify. If the fast idle is so easy to get to on this carb why did I pull it off the car every time to adjust it?? The Holley carb sitting on my 360 the fast idle screw is no problem to get to so I agree.. on that carb.. On this carb I have been messing with.. For whatever reason, maybe because it was converted to an electric choke (as I stated earlier) or older or something its a real pain!!! I didn't enjoy pulling the carb to adjust it.. Also to get into the weeds, about Holley, if you want to change the jets, better be good with the cup to catch the gas... and getting the dual feed line off all the time etc.. and don't get me started on the power valve that I can skip.. I usually keep a pretty good running motor and I like a well tuned engine and its nice when they stay that way so when its set I think Holley is usually on the money and when I was racing the one I had then gave me some pretty constant ETs.. That being said I knew guys that knew every air passage, gasket, bushing in a carb and they would modify them for alcohol etc.. I was never that guy.. For the most part I know what I don't know..(how about you?) I know that fast the idle screw is a nuisance on this carb and its just about screwed all they way in.. I hope its not compensating for nothing more than the arm with the screw in it is from the manual set up. Next show I get to and there are a bunch of Holleys in front of me I will check them out better.. As always I appreciate help. Jay
Sorry if you think so. Why you had to pull off a carb to adjust fast idle, I have no idea you tell me. All I can say, in the 50 years I've been working on cars , I've never run into that situation. This was a very popular replacement carb back in the day, did quite a few on mopars and other cars. Now, I think you're the one that's rude, intentionally rude. I went out of my way to say to not misinterpret my statement, since my experience was all easy adjustments; yet, you inserted a little "dig" in those parentheses. But, nevertheless, I'll answer your "question" . I don't know many things, there's a saying "you learn something new every day", well I've found that true for 50 years and counting.
 
Sorry if you think so. Why you had to pull off a carb to adjust fast idle, I have no idea you tell me. All I can say, in the 50 years I've been working on cars , I've never run into that situation. This was a very popular replacement carb back in the day, did quite a few on mopars and other cars. Now, I think you're the one that's rude, intentionally rude. I went out of my way to say to not misinterpret my statement, since my experience was all easy adjustments; yet, you inserted a little "dig" in those parentheses. But, nevertheless, I'll answer your "question" . I don't know many things, there's a saying "you learn something new every day", well I've found that true for 50 years and counting.

I suggest you read your initial statement again, you state as fact all the setting are "EASY" to adjust.. As in all Holley's everywhere ever made on every car, every situation.. Part of what I was looking for in this thread is an answer to the question, what is unique about this carb I happen to have? I am not going down more of this rabbit hole with you what "I am supposed to tell you" in your first sentence.. Or any more of your reply.. I have looked up some of your other posts, I didn't have to look far on one you stared and you alienated that guy.. I am sure there are many more. Your just on here looking for an argument.. I am on here looking for help.. I would a appreciate it if you left me alone from now on.
 
Auto Transport Service
Back
Top