View Poll Results: What's On Your Intake?
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Carbs
Registered User
Joined: Nov 2008
Posts: 8,501
From: Central Fl
Then when you make a statement like that you open yourself up to scrutiny. You stated it’s your opinion based on experiences. Is it your opinion or experience? C’mon you’re smarter than that.
Let me tell you the facts. In the last 6 months I’ve purchased a dozen or so QF or Brawler carbs. Roughly 10 of those had different jets in them vs what they’re supposed to have from their website. In fact one was supposed to have 78/86’s, it had 72’s and 83’s.
So my point is this, don’t expect ANYTHING to be good right out of the box anymore. And if you’re going to make a blanket statement like that please be able to back it up with facts, not opinion.
Thank you.
Let me tell you the facts. In the last 6 months I’ve purchased a dozen or so QF or Brawler carbs. Roughly 10 of those had different jets in them vs what they’re supposed to have from their website. In fact one was supposed to have 78/86’s, it had 72’s and 83’s.
So my point is this, don’t expect ANYTHING to be good right out of the box anymore. And if you’re going to make a blanket statement like that please be able to back it up with facts, not opinion.
Thank you.
Registered User
Joined: Dec 2016
Posts: 354
Then when you make a statement like that you open yourself up to scrutiny. You stated it’s your opinion based on experiences. Is it your opinion or experience? C’mon you’re smarter than that.
Let me tell you the facts. In the last 6 months I’ve purchased a dozen or so QF or Brawler carbs. Roughly 10 of those had different jets in them vs what they’re supposed to have from their website. In fact one was supposed to have 78/86’s, it had 72’s and 83’s.
So my point is this, don’t expect ANYTHING to be good right out of the box anymore. And if you’re going to make a blanket statement like that please be able to back it up with facts, not opinion.
Thank you.
Let me tell you the facts. In the last 6 months I’ve purchased a dozen or so QF or Brawler carbs. Roughly 10 of those had different jets in them vs what they’re supposed to have from their website. In fact one was supposed to have 78/86’s, it had 72’s and 83’s.
So my point is this, don’t expect ANYTHING to be good right out of the box anymore. And if you’re going to make a blanket statement like that please be able to back it up with facts, not opinion.
Thank you.
Registered User
Joined: Dec 2015
Posts: 104
trying to figure out how to run qjet like that on the street and down the track....
or need to find someone who can mod my carb more for me
Registered User
Joined: Jan 2010
Posts: 6,119
From: central Indiana
Your right, I probably shouldn’t say things like I did. It just annoys the hell out of me when people complain about the Q-Jet saying they are unreliable. GM made how many millions of QJets over the almost 50 year production run?! The vast majority worked very well. It especially annoys me when people are too cheap to buy the proper parts the fox what they have, but think nothing of dropping a few hundred bucks on a aftermarket carb. And don’t get me started on the people who bolt on a aftermarket universal carb and refuse to tune it any further than setting the idle speed.
Registered User
Joined: Nov 2008
Posts: 8,501
From: Central Fl
More importantly it needs to be VERY consistent. I’ve had a few Qjets on the dyno, fuel curve changes with even small pressure changes.
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Joined: Dec 2016
Posts: 354
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Joined: Oct 2014
Posts: 3,013
Going against the " Engine God's" will get you banished !
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Joined: Sep 2017
Posts: 5,220
From: St. Paul Minnesota
Your right, I probably shouldn’t say things like I did. It just annoys the hell out of me when people complain about the Q-Jet saying they are unreliable. GM made how many millions of QJets over the almost 50 year production run?! The vast majority worked very well. It especially annoys me when people are too cheap to buy the proper parts the fox what they have, but think nothing of dropping a few hundred bucks on a aftermarket carb. And don’t get me started on the people who bolt on a aftermarket universal carb and refuse to tune it any further than setting the idle speed.
Thread Starter
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Joined: Mar 2010
Posts: 3,886
From: Mt.Ary, MD
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Joined: Sep 2013
Posts: 2,935
I'm leaning heavily towards a q-jet, mainly because I don't like the block off plate on the spreadbore intake. I'm sure it works fine; I just don't like it.
Trimble wants me to put a 4500 on it, but then I need to change the intake and it needs cut, anyway.
I heard that the HP series 4150s are less cfm than their names suggest, like a 950HP is 750cfm. Don't know how much truth there is to it, but it makes shopping difficult.
I can say that the Edelbrocks and goggles are not even considerations.
Trimble wants me to put a 4500 on it, but then I need to change the intake and it needs cut, anyway.
I heard that the HP series 4150s are less cfm than their names suggest, like a 950HP is 750cfm. Don't know how much truth there is to it, but it makes shopping difficult.
I can say that the Edelbrocks and goggles are not even considerations.
Last edited by CANADIANOLDS; Apr 14, 2022 at 09:40 AM.
Registered User
Joined: Aug 2020
Posts: 637
From: Dallas
Your right, I probably shouldn’t say things like I did. It just annoys the hell out of me when people complain about the Q-Jet saying they are unreliable. GM made how many millions of QJets over the almost 50 year production run?! The vast majority worked very well. It especially annoys me when people are too cheap to buy the proper parts the fox what they have, but think nothing of dropping a few hundred bucks on a aftermarket carb. And don’t get me started on the people who bolt on a aftermarket universal carb and refuse to tune it any further than setting the idle speed.
My point is that if someone doesn't already have a Q-Jet to tune to their "racing and high performance" needs, I struggle to think that anyone would recommend a Q-Jet over a Holley 4150. If you already own the Q-Jet, it totally makes sense to tune it to your needs, or if you are trying to squeeze the most performance out of a stock-looking setup, definitely use the Q-Jet. But if you need to buy something, find a 4150 that best fits your needs and budget and go from there.
Last edited by NTXOlds; Apr 14, 2022 at 10:14 AM.
Chevy budget Olds powered
Joined: Jul 2011
Posts: 8,638
From: Elgin, Illinois
I ran a sniper for a year and have installed 4 now with no issues but I don't like them and the issues come down to quality and a bit of misleading marketing. I had lots of quality control issues and you really have to work to not get any RFI which our old cars are like a playground for RFI. Those efi kits are marketed towards people who don't know their head from their .... Well you know. I sold it went back to carburetor. Car is dead reliable and gets good mpg. What I will say is an AFR gauge and basic carb circuit understanding goes a long way but it seems the average hot rodder can't be bothered. I love the Edelbrock carbs for the street and for racing the 4150 can't be beat. One of the best carbs I ever used out the box was a little cheap 3310 750 Holley on my previous SBO. One the best carbs I have ever had has been also the 1405 Edelbrock on my cruiser . It's been. In service for over 15 years with a clean up which wasn't needed last year. That's all I have to say about that lol
Thread Starter
Registered User
Joined: Mar 2010
Posts: 3,886
From: Mt.Ary, MD
Out of Line, Everytime😉
Joined: Dec 2006
Posts: 10,136
From: Melville, Saskatchewan
Last edited by olds 307 and 403; Apr 14, 2022 at 12:39 PM.
Thread Starter
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Joined: Mar 2010
Posts: 3,886
From: Mt.Ary, MD
No, I'm contracting it out. I tried once, and it ain't work so good. But, yes, a wideband is in the plan.
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Joined: Feb 2009
Posts: 1,739
From: West Hartford, CT
When my engine was dynoed we compared my unoptimized but close Qjet to an unoptimized but close 4150 that BTR had and all they did was show a few (like 3 hp) difference each way at different points. It was a dead draw. That said, I subscribe to the above that the engine doesn’t know what’s metering fuel, if it’s configured and adjusted properly they will give similar, equal or at least good results. My love affair with the Qjet has plenty to do with the seamless transitions and combination of circuits that allow such good drivability and efficiency while still being able to support enviable performance but heir Achilles Heel is bowl capacity.
Once you get above 500hp I think you’re leaving Qjet’s sphere of influence unless they are really built and kept fed. I would love to have a port injected EFI which seems to me the only way to beat the drivability of the Qjet but I wouldn’t even know where anything goes, never mind tune it! For most of the rest, it’s 4150 based carbs, they have worked for 50+ years and continue to evolve. The TBI doesn’t seem to be worth the expense and tuning to me, but in fairness, I’ve never had my mitts on one.
Anyone have an oil or cylinder head thread we can discuss?
…
Last edited by bccan; Apr 15, 2022 at 03:08 PM.
Registered User
Joined: Sep 2013
Posts: 2,935
The Q jet would be my last choice for this guys application…there is no reason to use one unless forced to by rules.
On a single plane the Q jet needs a massive spacer to help it’s fuel distribution problems.
the fuel bowl is tiny. You are stuck with non removable boosters designed in the 60’s. The stock accelerator pump volume can’t deliver enough fuel for a big inch motor with a single plane.
On a single plane the Q jet needs a massive spacer to help it’s fuel distribution problems.
the fuel bowl is tiny. You are stuck with non removable boosters designed in the 60’s. The stock accelerator pump volume can’t deliver enough fuel for a big inch motor with a single plane.
Registered User
Joined: Nov 2008
Posts: 8,501
From: Central Fl
The Q jet would be my last choice for this guys application…there is no reason to use one unless forced to by rules.
On a single plane the Q jet needs a massive spacer to help it’s fuel distribution problems.
the fuel bowl is tiny. You are stuck with non removable boosters designed in the 60’s. The stock accelerator pump volume can’t deliver enough fuel for a big inch motor with a single plane.
On a single plane the Q jet needs a massive spacer to help it’s fuel distribution problems.
the fuel bowl is tiny. You are stuck with non removable boosters designed in the 60’s. The stock accelerator pump volume can’t deliver enough fuel for a big inch motor with a single plane.
Out of Line, Everytime😉
Joined: Dec 2006
Posts: 10,136
From: Melville, Saskatchewan
Hopefully a Qjet from a known builder, that will be ran down the 1/4 mile with a pretty aggressive cam BBO, turning decent rpm will perform without major hair pulling. He is probably already bald from the Fi Tech good times.
Registered User
Joined: Jul 2012
Posts: 2,991
From: Vancouver BC
Class racer is good source as to what is required
It starts at the fuel cell or fuel pick up point in a stock tank
Large fuel line 8 NA / 1/2 feed and return. {I have not seen anyone run a dead head set up}
Non restrictive fuel filter as in they don't run the inlet fuel filter
Big dollar fuel pump and regulator
Modified Qjet
This is just a quick overview its best to go to the source Class racers or NHRA stock super stock event
Its very common to see $1000 plus dollar fuel systems on these cars
Registered User
Joined: Jul 2012
Posts: 2,991
From: Vancouver BC
Registered User
Joined: Sep 2013
Posts: 2,935
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Joined: Oct 2014
Posts: 3,013
Out of Line, Everytime😉
Joined: Dec 2006
Posts: 10,136
From: Melville, Saskatchewan
Sinner! Some of us do consider it a swear word. I say he should try a 850 Carter Thermoquad, really stir the pot. They are all divorced choke except the 74 Ford 800 cfm and the aftermarket later 800 cfm model are electric choke, which I owned one. Some good things, like the adjustable primary metering rods and like most Carter carbs some hokey things, the choke sucked, almost no adjustment, it needed a special tool to adjust the air door and the o rings failed like usual. Too bad the new Street Demon wasn't available in the 850 and they fixed the full throttle fuel supply issue. They seemed to have fixed the rest of Thermoquad's usual issues. The Rochester carbs were by far the most refined factory carbs compared to thr Carter and Motorcraft carbs but this is a Street and strip car. Will it meet the task? Opinion and Experience😉 say, maybe not?
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Joined: Mar 2019
Posts: 104
AVS2 - 850 Brawer
I purchased a new version Edelbrock that says it is a 800CFM it is called AVS2 series and had installed it on my Hot SBO 350 in place of the older edelbrock style 750 cfm. It ran very well and had noticeable power gain. All of this was after 1.5 years of messing with a fitech.
I only got to drive the car once before putting it away for the winter but It was worth the swap noticeably and had similar driving characteristics as an FI.
I purchased a Holley 850 Brawler with electric choke over the winter an di, going to use it on my 500 CI street build.
Mark do you have any tuning advice for an 500 CI Olds 9-1 compression, Aggressive roller cam street car with ported heads and an Edelbrock high rise dual plane ?
Summer is just around the corner .
I only got to drive the car once before putting it away for the winter but It was worth the swap noticeably and had similar driving characteristics as an FI.
I purchased a Holley 850 Brawler with electric choke over the winter an di, going to use it on my 500 CI street build.
Mark do you have any tuning advice for an 500 CI Olds 9-1 compression, Aggressive roller cam street car with ported heads and an Edelbrock high rise dual plane ?
Summer is just around the corner .
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Joined: Jul 2012
Posts: 2,991
From: Vancouver BC
Registered User
Joined: Nov 2008
Posts: 8,501
From: Central Fl
I’m talking pressure, not volume. As mentioned when the pressure changed, so did the fuel curve.
Thread Starter
Registered User
Joined: Mar 2010
Posts: 3,886
From: Mt.Ary, MD
Registered User
Joined: Jul 2012
Posts: 2,991
From: Vancouver BC
Not all Qjet cores are equal, they differ by engine make and year.
I was taking to one class racer that was running a big block Vet, the Carb base, carb body and carb air horn were from different cars. Only the body in this case was numbers correct for the car. In this configuration it was faster than his other Qjets
I know the later larger cfm carb is popular with the q jet racers that were not class racing.
These sites might help reach your goal.
https://cliffshighperformance.com/
http://www.deanoscarbs.com/
https://classracer.com/classforum/index.php
I know of one record setting stock and super stock racer that builds his own carburetors so by no means is this a complete list.
Last edited by Bernhard; Apr 15, 2022 at 03:20 PM.
Registered User
Joined: Sep 2013
Posts: 2,935
1 I highly doubt you’re the guy the find the limit of the Q jet
2 we already know you are a different cat.
3 no
4 we already scratch our heads at what you do
Thread Starter
Registered User
Joined: Mar 2010
Posts: 3,886
From: Mt.Ary, MD
Registered User
Joined: Dec 2015
Posts: 104
Class racer is good source as to what is required
It starts at the fuel cell or fuel pick up point in a stock tank
Large fuel line 8 NA / 1/2 feed and return. {I have not seen anyone run a dead head set up}
Non restrictive fuel filter as in they don't run the inlet fuel filter
Big dollar fuel pump and regulator
Modified Qjet
This is just a quick overview its best to go to the source Class racers or NHRA stock super stock event
Its very common to see $1000 plus dollar fuel systems on these cars
It starts at the fuel cell or fuel pick up point in a stock tank
Large fuel line 8 NA / 1/2 feed and return. {I have not seen anyone run a dead head set up}
Non restrictive fuel filter as in they don't run the inlet fuel filter
Big dollar fuel pump and regulator
Modified Qjet
This is just a quick overview its best to go to the source Class racers or NHRA stock super stock event
Its very common to see $1000 plus dollar fuel systems on these cars
got the -8an line and pick up in the tank. Big non restrictive fuel filter. Good pump amd larger inlet fitting in carb. I know there will be limits with a qjet(specially with size of fuel bowl) but wanna get the most out of it...car runs great on the street, just looking for max while going down 1/4 mile.
