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1971 Chevelle SS 454
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Discussion Starter · #21 ·
N
Back to your Qjet. Very likely replaced somewhere along the way with an stock off-the-shelf rebuild, which would likely have truck numbers. That's OK. I know one of the carbs Eric did for me was off a motor home ( from Tom mobely ) and the other maybe a md 70's something or other. The RV one is800+ cfm, while the 70s small block Camaro is a standard 750 cfm version.

You COULD try to find the correct casting #, and again Eric is a restoration pro, so may be able to help you there as well.

PS I decided not to run either, but I really ogth take a shot of the one Eric restored. I don't wear jewlery, but that thing is uber bling! in an OEM way. Just friggin' stellar finish. Reminds me to do that.

If the carb seems to run fine, run it! As long as Qjets dont get too much fuel pressure, once in tune, they do tend to remain that way.
Thank you guys I talked to Eric, he seemed to think it might run different depending on engine set up as mentioned above. I ended up ordering one with the right number just because im OCD lol it does have the matching engine and transmission in it. I do question the intake manifold not sure if they would of used it on the engine or not the casting number is

B2070
3955287

It was 20FEB70 date. is it possible they would of still used this on a 1971? Thanks guys!
 

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Back to your Qjet. Very likely replaced somewhere along the way with an stock off-the-shelf rebuild, which would likely have truck numbers. That's OK. I know one of the carbs Eric did for me was off a motor home ( from Tom mobely ) and the other maybe a md 70's something or other. The RV one is800+ cfm, while the 70s small block Camaro is a standard 750 cfm version.

You COULD try to find the correct casting #, and again Eric is a restoration pro, so may be able to help you there as well.

PS I decided not to run either, but I really ogth take a shot of the one Eric restored. I don't wear jewlery, but that thing is uber bling! in an OEM way. Just friggin' stellar finish. Reminds me to do that.

If the carb seems to run fine, run it! As long as Qjets dont get too much fuel pressure, once in tune, they do tend to remain that way.
Decided not to run either? Are they for sale
for sale?
 

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Dont have a price in mind.
I dont know much about the numbers...but have aways had good luck with Q-jets. What cfm is the one you would sell. I'm building a Camaro after this Chevelle...and don't want to run a Holley if I can find a decent Q-jet.
 

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And how many of those heads with 2.06"int./1.72" exh. valves came on 454cid engines in the EARLY 70's???? If you read the post of mine that you quoted, you would see that in the very first sentence I made it clear that I was speaking of 454cid cylinder heads, since the title of this thread indicates that the OP is speaking about the 454cid engine in his car. And AFAIK, NONE of the 454 engines came with heads that had the 2.06" intake and 1.72" exhaust valves. So unless I'm all wrong about that, then there was nothing "misleading" about my statement at all, nor was it a "broad" statement since I made it clear in the beginning that I was speaking specifically about 454 engine cylinder heads.
All LS4 and LS5 454's came with those valve sizes fwiw! Those would include the 336781 and 353049 heads everyone looks for. This was not a personal attack on you, I was just stating facts and the facts are the majority of 454 BBC iron heads were oval port with 2.06"/1.72" valves. In 1970 there were 4298 LS5's, 9502 in 1971 and 5333 in 1972 and this is just for 1970-72 A-Body vehicles and does not include the later 1973-75 Chevelle/Laguna/El Camino's, 1970-76 full size Chevrolets, 1970-74 Corvettes (over 21,000 LS4/LS5), 1970-72 GMC Sprints and all early 70's light duty trucks which includes pickups and vehicles like C30 based ambulances and motor homes to name a few. So, the vast majority of 454's in the early 70's were equipped with 2.06" intake and 1.72" exhaust valves.

And to the OP, sorry for taking this a bit further off on a tangent.
 
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Carbs are engine specific. There is no way that the Uremco carb will work well out of the box. Carbs need to be calibrated to your specific engine. You can't order one out of a catalog and expect it to run well. It will start and run but you must change jets and metering rods to match the engine. I would contact a specialty carb guy in your area to rebuild yours and tune it to your engine or to tune the Uremco one. The overall CFM for all of them is 750. There are some larger 800 ones but they are rare and they were not for Chevrolet.

Obviously a carb matched to specific engines is ALWAYS better, but I have always found Quadrajets to be less concerned about what the were bolted to than about any other carb. When I was a kid in the 80's, we freely mixed and matched whatever we had, and they all ran pretty good if they didn't need major help. My 69' C10 with the 307 ran the whole time I had it with a 69' Camaro SS L48 carb on it, and could embarrass a LOT of 80's era cars, and the first 7-8 years I had my Chevelle with both the totally worn out and then rebuilt and hopped up 350, it ran with the QJ off my 73' 454.
 

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1971 Chevelle SS 454
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Discussion Starter · #32 ·
All LS4 and LS5 454's came with those valve sizes fwiw! Those would include the 336781 and 353049 heads everyone looks for. This was not a personal attack on you, I was just stating facts and the facts are the majority of 454 BBC iron heads were oval port with 2.06"/1.72" valves. In 1970 there were 4298 LS5's, 9502 in 1971 and 5333 in 1972 and this is just for 1970-72 A-Body vehicles and does not include the later 1973-75 Chevelle/Laguna/El Camino's, 1970-76 full size Chevrolets, 1970-74 Corvettes (over 21,000 LS4/LS5), 1970-72 GMC Sprints and all early 70's light duty trucks which includes pickups and vehicles like C30 based ambulances and motor homes to name a few. So, the vast majority of 454's in the early 70's were equipped with 2.06" intake and 1.72" exhaust valves.

And to the OP, sorry for taking this a bit further off on a tangent.
You are fine learning a lot.
 
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