quick fuel vs pro systems.

[Troy Patterson]

A couple of thing to look at with the larger carb, on the dyno look at what effect it has on peak torque, not just HP. If it picks up torque at or even below peak torque it should pick up time as well. A 1250 on my small block matched a 1050 from a few hundred RPM BELOW peak torque and made more torque and HP from there. It was worth .05 in the 1/8 and a .10 in the 1/4 mile. Not always the case, induction and combustion efficiency will play into how large you can go and see a gain.

How you build the carburetor determines to some extent the torque and horsepower curves. And I've witnessed increases in torque well below peak with larger carbs - "in the real world" - and on the dyno. Interestingly, I see more gains "in the real world" than the dyno typically shows. A small difference from one carburetor to another on the dyno can drive and perform like two completely different engines - unless the two carburetors are built the same or substantially the same - with only cfm being the difference.

Example: I saw a 15 lb. torque gain (chassis dyno) on one engine with one carburetor over another, then test drove the car with the added weight of another 200 lb. person in the car to offset the torque gain, the car was much more responsive and clearly spun the tires where the did not with the other carburetor.

I dyno'd a 1 1/2" dia. venturi carb against a 1 3/8" dia. venturi carb. The smaller carb was considered correct for the application, the larger carb too big. The larger carb allowed the engine to take full throttle on the dyno 1100 rpm lower than the smaller carb and made 25 lbs more torque. Both carbs were prepared by carburetor builders and tuned to / for the engine.

Troy Patterson TMPCarbs.net TMP Carbs

[Jay C.]

A couple of thing to look at with the larger carb, on the dyno look at what effect it has on peak torque, not just HP. If it picks up torque at or even below peak torque it should pick up time as well. A 1250 on my small block matched a 1050 from a few hundred RPM BELOW peak torque and made more torque and HP from there. It was worth .05 in the 1/8 and a .10 in the 1/4 mile. Not always the case, induction and combustion efficiency will play into how large you can go and see a gain.

Since I posted that it picked up all the way through the test range (5k-7200) it obviously picked up torque all the way through. The only way it would make more HP at the same rpm is if it made more tq. Peak tq was at about 5400, but it was pretty much flat for several hundred RPM. I would expect the 1250 to run a little quicker than the 1200 in this case, though not much. Average HP and TQ was higher with the 1250.

[RTR-1]

I was wondering where are the Quick Fuel parts made? I thought someone said they are made in China

[RayJE Carburetors]

I've built HP1000 based alky carbs that will run within .01-.02 of a good 1050. 1/8th mile here.

what booster are you using to do this on methanol...

[Jay C.]

I've built HP1000 based alky carbs that will run within .01-.02 of a good 1050. 1/8th mile here.

what booster are you using to do this on methanol...

Braswell. I sent you a PM.

[Troy Patterson]

As far as dyno results go, a 1250 with its big throttle blade on a engine that size is usually good for at least 15-25 h.p. over the 2" blade 1200 you tested on the dyno. But on the racetrack the 1250 is typically slower overall in that size of an engine and a little inconsistent in operation on the front half of the racetrack (playing the averages).

So playing the averages the 1200 2" blade carb would be a better call in the real world.

However, there are exceptions to every rule.

Patrick James
PRO SYSTEMS

I'm a little puzzled by this comment about the 1150 based version of the carb being faster than a 1250 on an engine over 500 cid let alone a healthy 400 + cid engine?

Oh God, am I one of those stalker types Patrick was talking about?

Troy Patterson TMPCarbs.net TMP Carbs

[jmarkaudio]

Oh God, am I one of those stalker types Patrick was talking about?

Troy Patterson TMPCarbs.net TMP Carbs

Boy, are you in trouble now...


I think it may be several factors, the ability of the engine to atomize the particular fuel used, enough for the combustion chamber and dome design of that engine. I also wonder what effect the plenum size has to do with it, if a smaller versus a larger plenum changes the needs in carb size. On mine, everything I've put on bigger makes more power and has run faster.

[Troy Patterson]

Oh God, am I one of those stalker types Patrick was talking about?

Troy Patterson TMPCarbs.net TMP Carbs

Boy, are you in trouble now...


I think it may be several factors, the ability of the engine to atomize the particular fuel used, enough for the combustion chamber and dome design of that engine. I also wonder what effect the plenum size has to do with it, if a smaller versus a larger plenum changes the needs in carb size. On mine, everything I've put on bigger makes more power and has run faster.

Dang, it's too late to delete my post, maybe he won't notice - shhhhhh

Troy Patterson TMPCarbs.net TMP Carbs

[hitchcock]

I had great luck with my two 950's from Pro Systems. When you get a carb from Patrick you also get top notch customer support. All e-mails and phone calls are answered or returned promptly. I cant wait to build a big boy motor and try out some SV1's!!

[bknthda]

I run a Quick Fuel carb and have no complaints with the performance or the customer support from them. I did have to make some jetting changes to mine after I got it, but they helped me out. I had to remove the p/v in the rear and just jetted it the same as the front. I ended up dynoing with the recommended jetting and it was spot on. I have also used APD carbs. I had one that we could not get right. We as in APD and I. They ended up refunding me the full price of the carb. I also had another APD at the same time that was run on our drag car and it was the best carb we ever ran and was still on the car when we sold it. It was more consistent and we had to do nothing to it, but adjust the idle speed. I would recommend either one based on operation and customer support. I have never used a Pro Systems but have heard nothing but good about them also.

I don't have a complaint about my QFT 850 (unless parts came from China) but my experience with tech support was dissapointing! With no info on the emulsion jet sizing or placement, I first emailed then left a voice mail with NO RESPONSE whatsoever This forum saved the day, I Tunerized it.

[Troy Patterson]

I built a couple of carbs with Quick Fuel's billet bases and metering blocks and liked them very much - see picture.



My experience with Quick Fuel's customer service was good. Maybe it's worth adding the center sections used with this dual carb application are BLP Products.

I've never dealt with or talked with Pro Sys, but I have worked on / tuned a few of their carbs - see picture. I digitally altered the Pro Sys stickers to my own. Is this picture a shameless plug?

Apparently, I'm still working on that stalker thing.



I've got to say there are a number of good / great carburetor builders besides these two mentioned here. BLP Products and Braswell come to mind as innovators with great products, I'm sure there are others not springing to mind at the moment. How about you guys telling us of all the carburetor modifiers and builders you know. Let's see how many of them there are.

It's funny that only those two are mentioned as though they are the only ones worth considering, so I thought I'd use this thread plugging QT and Pro Sys to show off my own work . The internet is an interesting place for sure.

Troy Patterson TMPCarbs.net TMP Carbs

[Keith Morganstein]

How you build the carburetor determines to some extent the torque and horsepower curves. And I've witnessed increases in torque well below peak with larger carbs - "in the real world" - and on the dyno. Interestingly, I see more gains "in the real world" than the dyno typically shows. A small difference from one carburetor to another on the dyno can drive and perform like two completely different engines - unless the two carburetors are built the same or substantially the same - with only cfm being the difference.

Example: I saw a 15 lb. torque gain (chassis dyno) on one engine with one carburetor over another, then test drove the car with the added weight of another 200 lb. person in the car to offset the torque gain, the car was much more responsive and clearly spun the tires where the did not with the other carburetor.



Troy Patterson TMPCarbs.net TMP Carbs

I am clearly not a carb guru. I tune holleys like most do, but I happen to like Q Jets. I always wondered why you can have two identical part number Q-jets, build and tune them the same, but one will just kick the butt of the other one in responsiveness as you described?

[jmarkaudio]

I am clearly not a carb guru. I tune holleys like most do, but I happen to like Q Jets. I always wondered why you can have two identical part number Q-jets, build and tune them the same, but one will just kick the butt of the other one in responsiveness as you described?

I know Tuner does a few things with Q-Jets, start a thread and maybe he will share.... One thing I do know from talking to him is that some of the mass rebuilders screw with some of the passages for whatever reason... and screw them up.

[Aukai]

I don't have a lot of experience with after market carbs but the 2 I have gotten from Pro Systems worked very well for me. 950 HP for my old 454 and the Dominator Mike Lewis got from Pro Systems that made 900 HP on my pump gas 555.

[rmcomprandy]

[quote="PRO SYSTEMS"]Jay C you are correct I do tell my stalkers what I "actually" think. I don't play the PC thing with them. I call them out. Most of my stalkers (every successful company has them...when I lose them I will worry) are here just to rattle cages and thump their chests or stir up emotions, they really are not trying to help in most cases. They try to come up with an angle to say the exact opposite of whatever you say and prove their case. They have an agenda, hidden or otherwise.

Think of them as Democrats versus Republicans. They are obsessive compulsive types most often that really hate it when they see someone succeed and it keeps them up nights and they even relish when they see a failure even though we should all have a common goal.

So don't take it too serious.



This is a true, unembelished story about Pro Systems. Maybe they do good work and maybe they don't but, I'm never going to put myself in position again to find out.
In 2003, when the EMC was in it's infantcy I recomended Pro Systems to a competitor friend of mine for getting his carburetor modified because I had heard some good things.
To make a very long story short, that 1150 Dominator carb caused the engine to lift 3 piston top ring lands and anneal 6 of the top rings in just 3 dyvo runs. After rebuilding the short block and doing another valve job we made some air bleeds, (Patrick's are a different thread size than anybody else's in the industry), and tuned that carburetor close; 8 high speed air bleeds smaller and 10 jet sizes larger.
I could and would have kept this all under wraps UNTIL he, (the engine and carburetor owner). called Pro Systems to get an assortment of THEIR air bleeds and was told under no uncertain terms that something else was wrong because their carburetor "just wouldn't do that" and the tuner, (me), must be "out to lunch and didn't know what he was doing".
Well, to end it ... that big block Chevy finished 4th in that 2003 EMC contest so it must have been tuned fairly close.