Are there any good "trick" carbs?

[bigjoe1]

The biggest area where the trick carbs shine is in driveabilty. I have run some very expensive trick carbs on the dyno, and I have NEVER seen any HP increase. BUT, they sound better, and drive better and in general act better,. The bottom line is, if your carb was dialed in for max HP on the dyno, the trick carb will not make any more HP, but its manners will be much nicer ect.I keep a bunch of dyno carbs on the shelf, and I never get beat by the trick piece.


JOE SHERMAN RACING ENGINES

[axegrinder]

Joe you just explained what it took me a few years to figure out. I have a 7 year old Quickfuel that keeps making more power than everything that is dynoed against it. And it is an undrivable POS under 5000rpm!

[jmarkaudio]

With the advent of AFR meters and data loggers, the gap should be closing. Airflow being equal, I can't see a "trick" carb being significantly better than a properly tuned out of the box unit IF you have the will to take the time to tune it correctly for your combo. The trick carb may be necessary for an all out Comp, PS, or Cup type classes where any gain is a plus, just not needed for bracket style racing. Unless you need more than 1250 CFM.....

[Doug Schriefer]

And yet even you say how when you bolt on your Braswell carburetor it makes more power than the stuff you've tuned... So based on your logic stated here you should be able to make as much (and actually more since you're there tuning on it) HP than your Braswell..

Not sure where you came up with that statement. I've run a lot of Braswell carbs on the dyno and they have always made really good power. The Braswell stuff usually does better than any customer carb but the usual customer carb is an older Holley non-HP style carb. When I've done Braswell vs. UltraHP carb type of tests I usually don't see much if any difference on the dyno.

Braswell does have some stuff that Holley doesn't have, for instance the extra fuel circuit options that would be important for circle track guys. So if someone needs to run in a class where mileage is important then a carb like that could be the difference between winning and sitting in the pits getting a tank of gas.

Just going by what you've stated in the past from a previous thread.

I'll be back on the dyno in a few weeks with another BB Mopar combo. I'm going to plan some more time for carb testing then since the dyno operator has a really nice Braswell carb that should make for an interesting comparison. This Braswell jewel is the classic "dyno queen" that usually makes 20 or 30 hp more than the customer's carb. So that will be the true test. We'll see what the dyno says and what the wideband (and the spark plugs) tells us.

The additonal circuitry is actually as important if not more so on High end Drag race stuff to tune the recovery at the gear changes.

[Doug Schriefer]

what does Brasswell offer for drag racing any better than Holley ?is there any ? just curious

The first thing is Knowledge!

But over and above that is design.

-On the 2x4 carburetors the jets are moved so they can not become uncovered when you launch the car.
-All of the carburetors are designed specifically for racing so they are engineered to be lighter more durable castings.
-Sizing We're able to offer different sizes than other castings.
-Booster designs are adjusted the application to get the fuel where it needs to be.

[John W]

I let a buddy borrow my Braswell 4500 for the dyno. It made the same power as his 8896 on his ~675hp sbc, but the fuel curve looked much better with the Braswell and it also had much better throttle response. I took both carbs with me to the track the following weekend and the Braswell was over a tenth quicker and nearly all in by the 330'.

Doug, from reading some of your posts recently I gather you made a move????

[Doug Schriefer]

Doug, from reading some of your posts recently I gather you made a move????

Yup, no Longer with BG... Life is much better with Braswell.

[Ron Golden]

I dyno and tune quite a few engines every year and have always had excellent results with BLP carbs. However, if you take a good Holley and tune it on the dyno then replace it with a custom carb your usually not going to see any BIG HP increase. In other words it's hard for the average guy to justify spending another $1000 to pick up a few HP or a tenth or two on the strip. That money could be spent more effectively on other areas of the car.

The one exception that comes to mind is when your running a Holley Street Avenger carb. I've had 4 of these carbs on different engines on the dyno and couldn't get any of them to work.

Ron

[Jason G]

I let a buddy borrow my Braswell 4500 for the dyno. It made the same power as his 8896 on his ~675hp sbc, but the fuel curve looked much better with the Braswell and it also had much better throttle response. I took both carbs with me to the track the following weekend and the Braswell was over a tenth quicker and nearly all in by the 330'.

Doug, from reading some of your posts recently I gather you made a move????

John,

Thanks for chiming in on this. I was going to post the same thing. The other thing is your Braswell idled clean down to ~800 RPM....Not to shabby for a 282 @ .050 duration solid roller cam. The Holley wan't just real happy even at ~1050 RPM.

And for a continuation of this test..........

I sent my same stock 8896 Holley 1050 HP Dominator off to Pro Systems over the winter to be "tricked". So far the car slowed down about . 08 ET/1 MPH over the stock Holley. No other engine changes (I did cut out the old cage and put in a new one - the new one should be slightly lighter - back section is now 1-5/8" vs. 1-3/4 for the old). Granted the DA was ~100' worse and I have yet to tune ANY on the Pro Systems carb. It appears to be pretty rich and is a blubbering pig driving around the pits and will run you out of the garage in less than a minute (and yes the floats are fine). The Holley had been tuned on the dyno and further refined at the track and was fairly clean part throttle after adding a power valve in the front. I'm sure I can get the .08 / 1 MPH back with tuning the PS modified carb as well as clean up the driveability, but then what exactly did I pay 500 bones for?? A sticker, running a cartridge roll over the top of the venturi's, and some pretty red boosters??? A ricer carb, flashy......but no more GO than "stock".

So.......as far as I'm concerned at this point, if you know your way around a carb and don't mind doing some tuning yourself(provided your carb has adjustble features...air bleeds, etc.), don't waste your money on "trick" carbs unless you are going to jump in with both feet and pony up for a Braswell. That's been my experience anyway.

Jason G.

[jmarkaudio]

I dyno and tune quite a few engines every year and have always had excellent results with BLP carbs. However, if you take a good Holley and tune it on the dyno then replace it with a custom carb your usually not going to see any BIG HP increase. In other words it's hard for the average guy to justify spending another $1000 to pick up a few HP or a tenth or two on the strip. That money could be spent more effectively on other areas of the car.
Ron

Two tenths would be enough to consider, but that would be an extreme case and most likely replacing one that did not have the metering close. I could see up to a tenth if the factory carb was given the right adjustments. Again, assuming the same flow between the carbs.

I let a buddy borrow my Braswell 4500 for the dyno. It made the same power as his 8896 on his ~675hp sbc, but the fuel curve looked much better with the Braswell and it also had much better throttle response. I took both carbs with me to the track the following weekend and the Braswell was over a tenth quicker and nearly all in by the 330'.

That is not a fair fight, an old style 9375 would have been a better match. My 8896 was a ROYAL pain, the intermediate and transition circuit are both excessively rich. It would randomly fall on it's face coming up on the converter. A little bit of work can make them better without spending $1000. Sounds like it was made "Pretty", but how about the carb companies offering some budget choices that work for those that don't have the knowledge or will to fix it themselves, rather than a pretty one that doesn't work any better. Get the metering relatively close, not everyone need a Pro Stock level carb.

[RayJE Carburetors]

if it wasnt For BLP there would be no HP Ultras.... they are just BLP metering blocks and baseplates.

i get more UltraHPs new out of the box before even run.. sent to me than anything.....


there must be something to offer the customer apart from a sticker on the bowls .



to some extent some comments are correct .... the average bracket racer might be best to purchase an out of box HP holley... or ultra HP if they want the Bling of billet blocks.......and it would surfice his needs.
it would be like a guy building a 500HP 383 chev.. getting a set of complete Pro action heads and sending them off to Darin Morgan to work magic on..... the end result would guarenteed be better but the out of box deal would have done the job and be happy.

Same with a carburetor.....sometimes an out of box carb will work and do the job fine .......... for someone who wants to spend $500 working it over they will more than often get what they pay for ......too many people race dynos ........ if you put a bigger carb on a dyno.. and tune it ...you will make more power.... go to the track see what happens.

There will always be a market for a custom carburetor....with all the new exotic fuels these days... the out of box holley is not Optimum.....

i read a comment on here recently about how the carb builders should be scared... that with the availablity of Wideband lamda sensors... anyone will be able to tune there carb.... thats true.......but ya had the capabilty before.....tune by the seat of ya pants......dont tune for a specific A/f number....... i had a guy call the other day and say that he has a problem with a carb i just did.. he just purchased a FAST o2 logger ............he said that the his FAST A/F logger says that on the start line on the 2 step the air fuel is 15 - 16 to1 and when he side steps the clutch the A/f drops to 11.5:1 and then at the end of the 1st gear its 13.2 then back to 12.2 in secondon the change then at the end of 2nd its 13.0 and 3rd its 12.3 and 12.9 and 4th its the same

he says that his mate said that it has be be 12.9 and flat...and that it needed a bigger powervalve becasue it was so lean on the 2 step...

i asked him how he went and he said Oh yeah good ..... it went 2 tenths and 1 MPH better than its ever gone


this is the sort of people ya thing you battle with

AndyF there is more to Building a `trick`carb than jets. airbleeds ,emulsion bleeds......

there are also `trick` carbs and `trick` carbs

[John W]

That is not a fair fight, an old style 9375 would have been a better match. My 8896 was a ROYAL pain, the intermediate and transition circuit are both excessively rich. It would randomly fall on it's face coming up on the converter. A little bit of work can make them better without spending $1000. Sounds like it was made "Pretty", but how about the carb companies offering some budget choices that work for those that don't have the knowledge or will to fix it themselves, rather than a pretty one that doesn't work any better. Get the metering relatively close, not everyone need a Pro Stock level carb.

The point was to illustrate that dyno #'s don't necessarily illustrate how well a carb will et. Here you have 2 carbs that make the same dyno power, yet there's over a tenth difference between the two on the track.

[harry k]

The point was to illustrate that dyno #'s don't necessarily illustrate how well a carb will et. Here you have 2 carbs that make the same dyno power, yet there's over a tenth difference between the two on the track.

well , what about the traction part/weather change from one pass to the other?
i think if there was a difference more than a tenth ,than you have a point ,thats too close ! IMHO

[Doug Schriefer]

The point was to illustrate that dyno #'s don't necessarily illustrate how well a carb will et. Here you have 2 carbs that make the same dyno power, yet there's over a tenth difference between the two on the track.

well , what about the traction part/weather change from one pass to the other?
i think if there was a difference more than a tenth ,than you have a point ,thats too close ! IMHO

Agreed when testing you need to monitor weather, track conditions, etc. to see what is actually happening. It could have been a lot more than a tenth difference or less...

That said there are racers that would kill for a tenth... That is a HUGE difference.

[ZIGGY]

Some years ago a tech at Braswell told me that the
Cup guys would test multiple carbs of the same
configuration because there would be enough
hp/driveability variation to make such effort
worthwhile(which I know in Cup doesn't have to
be very much). The guys on this board with Cup
connections can confirm or deny the accuracy of
this (old) hearsay.