Street Demon Carb
Thread Starter
Intermediate
Joined: May 2015
Posts: 31
Likes: 0
From: New Jersey
Street Demon Carb
So I am looking at the Street Demon carb, but I am conflicted with 625cfm vs 750cfm. the previous owner put a 850 on it, (need to verify for accuracy of this) and it's just too much for how little mods have been done to the car. The car also apparently has a Comp Cam in it, I can hear a bit of lope so it's probably not really an aggressive one. Other than that it's mainly headers and the valves and what not that would have been changed with the cam. Any ideas on the 625 vs 750?
Racer
Joined: Jul 2013
Posts: 307
Likes: 19
From: Kirkland WA
So I am looking at the Street Demon carb, but I am conflicted with 625cfm vs 750cfm. the previous owner put a 850 on it, (need to verify for accuracy of this) and it's just too much for how little mods have been done to the car. The car also apparently has a Comp Cam in it, I can hear a bit of lope so it's probably not really an aggressive one. Other than that it's mainly headers and the valves and what not that would have been changed with the cam. Any ideas on the 625 vs 750?
Instructor
Joined: Apr 2015
Posts: 131
Likes: 26
From: Fort Valley Georgia
I asked a couple of my mechanic friends the same thing. They said the 625 was as high as they would go on a relatively stock motor. I plan on ordering a 625 street demon as soon as funds permit. They have really good review ratings on Summit.
Le Mans Master
Joined: May 2003
Posts: 8,876
Likes: 3,556
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
I have the 625 Street Demon on my 73- relatively stock L-82 .
Had it for a year- and have logged almost 5000 miles on it. Last June right before a 3000 mile trip on the Hotrod Power Tour- I was checking the filter on the Quadrajet -and the fitting was stripped out. Read BAD reviews on buying a "rebuilt" or "remanufactured" Q-jet- so I thought the Demon was a good replacement.
After basically bolting it on-(had showed up on my doorstep the next day from Summit) had enough vacuum inputs - and required very little modification to the throttle cable bracket. I then drove 3000 w/ very little tuning. It performed FLAWLESSLY- sitting in traffic for over an hour- started right back up after refueling. The car will sit for weeks- just push the throttle to the floor-release-turn the key-and it fires immediately.The mileage was a respectable 15MPG for the trip w/ 3.55 gears and the stock 4 speed Muncie.
I am headed out Friday for another 3000 mile trip on the Hotrod Power Tour- and the carb is one thing I am not worried about!!!
Had it for a year- and have logged almost 5000 miles on it. Last June right before a 3000 mile trip on the Hotrod Power Tour- I was checking the filter on the Quadrajet -and the fitting was stripped out. Read BAD reviews on buying a "rebuilt" or "remanufactured" Q-jet- so I thought the Demon was a good replacement.
After basically bolting it on-(had showed up on my doorstep the next day from Summit) had enough vacuum inputs - and required very little modification to the throttle cable bracket. I then drove 3000 w/ very little tuning. It performed FLAWLESSLY- sitting in traffic for over an hour- started right back up after refueling. The car will sit for weeks- just push the throttle to the floor-release-turn the key-and it fires immediately.The mileage was a respectable 15MPG for the trip w/ 3.55 gears and the stock 4 speed Muncie.
I am headed out Friday for another 3000 mile trip on the Hotrod Power Tour- and the carb is one thing I am not worried about!!!
Le Mans Master
Joined: Apr 2001
Posts: 5,941
Likes: 281
From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
With Demon carbs I have always found smaller is better. For some reason if you go too big they become very hard to tune properly. I had a 650 on my zz4 and it was great, but had to be rejected out the box. A friend put a 750 on his 350 and could never get it running right. He went down to the 650 and was able to get it right.
Race Director
Joined: May 2006
Posts: 18,710
Likes: 2,574
Torker II
The Torker II is a single plane manifold. For you application you want a dual plane manifold, look at the Performer series.
Last edited by MelWff; Jun 3, 2015 at 12:15 PM.
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Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
I had the torker on my 454 the po stuck it on so the hood would close, I swapped out to a base model performer and man could you feel the difference off the line, if you are not revving to 6500 the toker will hurt not help.
With the carbs I am looking at holley clones like the demon or quickfuel,
I thought the qjet was the answer but way too many cons...I like easy and simple...
Racer
Joined: Mar 2013
Posts: 298
Likes: 2
From: Orange Park Florida
Carb
I would go with a carb that shares a fuel well like an eddy or quadrajet. If you don't open the back barrels up on a holley configuration the gas gets stale and gums up and causes other problems. I would stay away from holley design. The general had it right with the quadrajet.
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
I was a bit bored...waiting for it to cool off to slap the supercharger back on the daily driver...It would be really fun to sit back and watch this turn into a Qjet vs all the other thread....
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Is the motor otherwise a fairly stock 350? If so, you won't need more than 625cfm. What carb and manifold do you have on now? Looks like one of the main selling points of the Street Demon is a crisp (smaller) primary action. That is a good thing, but you'll get that and a lot more with the old Quadrajet.
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
The Street Demon is similiar to a Thermoquad. People seem to like them, as they are simple and have the small primaries for great low-end torque. I would have no problem using one. If you do get one, please post your results.
Thread Starter
Intermediate
Joined: May 2015
Posts: 31
Likes: 0
From: New Jersey
It's gonna be a couple months until I get the new carb and intake, but I'll definitely post how I like the combo when it gets put on.
Instructor
Joined: Nov 2013
Posts: 220
Likes: 17
From: Pasadena MD
I've already decided to go with the Demon, but going with the 650 because I couldn't find a 625 with a mechanical secondary. I just need to decide on the intake now. Lol
It's gonna be a couple months until I get the new carb and intake, but I'll definitely post how I like the combo when it gets put on.
It's gonna be a couple months until I get the new carb and intake, but I'll definitely post how I like the combo when it gets put on.
Race Director
Joined: May 2006
Posts: 18,710
Likes: 2,574
Which Demon Model?
I've already decided to go with the Demon, but going with the 650 because I couldn't find a 625 with a mechanical secondary. I just need to decide on the intake now. Lol
It's gonna be a couple months until I get the new carb and intake, but I'll definitely post how I like the combo when it gets put on.
It's gonna be a couple months until I get the new carb and intake, but I'll definitely post how I like the combo when it gets put on.
Instructor
Joined: Apr 2015
Posts: 131
Likes: 26
From: Fort Valley Georgia
I was looking at the 1901bk. It didn't have as many reviews. But the 1901 did. And I don't think the color would make a difference. If it did the black ones would be faster. Lol.
Last edited by GaToy; Jun 3, 2015 at 07:40 PM.
Instructor
Joined: Apr 2015
Posts: 131
Likes: 26
From: Fort Valley Georgia
Instructor
Joined: Apr 2015
Posts: 131
Likes: 26
From: Fort Valley Georgia