Fine Tuning a 360 Magnum with a Brawler "Double Pumper"

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Or you could bolt on an Ede 650, back the a/f screws out 1.5 turns, and burn rubber all the way down the street. :thankyou:
 
RustyRatRod said:
A 650 dp on a 5.9 Magnum should be DAMN close. If it was truly puking black smoke out, what you should have done was sent it back. Something is WRONG.
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Thats why I told him early on to take it apart and measure it. I've seen them come with all 4 emulsion holes open. I had one that I know wasn't touched when I got it had one idle feed restrictor .004 bigger than the spec sheet called for and the other IFR on the same block didn't have a hole in it!!!

No wonder he couldn't get a decent idle lol.
 
RustyRatRod said:
A 650 dp on a 5.9 Magnum should be DAMN close. If it was truly puking black smoke out, what you should have done was sent it back. Something is WRONG.
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It wasn’t puking smoke I kind of exaggerated but I was able to see black smoke coming out of the tailpipe. When I went down from 71s to 68s the smoke went away but the plugs were still black, 66s plugs are brown. Probably could go smaller but it lean surges with 64s so I’ve stuck with the 66s.
 
Johnny Dart said:
Or you could bolt on an Ede 650, back the a/f screws out 1.5 turns, and burn rubber all the way down the street. :thankyou:
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I think I would blow apart my tranny and rear diff before I could burn the tires that much lmao. 200k original tranny and 8.25, I know the 8.25 is a proven axle but at 200k it’s probably not up for the task anymore. Plus the AX-15 tranny from 1992 is only “rated for 300ftlbs at the crank” and watching a video of an almost identical setup of my engine making 410ftlbs I think I’m just a little outside its rating
 
I’m also assuming messing with the bleeds will mess with my vacuum levels? I’m pretty sure everyone here had the same reason when I originally stated back a couple pages that I had 20 inches of vacuum at idle warm, and I can actually increase it if I leaned it out more. I think someone said they thought my throttles were closed too much or something?

Anyway, it seems like 20 inches is a crazy amount of vacuum for an engine even as mild as mine is, so is that potentially something causing issues or is it just weird to have this much?
 
jmanhoff said:
I’m also assuming messing with the bleeds will mess with my vacuum levels? I’m pretty sure everyone here had the same reason when I originally stated back a couple pages that I had 20 inches of vacuum at idle warm, and I can actually increase it if I leaned it out more. I think someone said they thought my throttles were closed too much or something?

Anyway, it seems like 20 inches is a crazy amount of vacuum for an engine even as mild as mine is, so is that potentially something causing issues or is it just weird to have this much?
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The milder the engine, the more vacuum it creates. As I said, I would put that carb back stock and send it back. If you got it from Summit, they will gladly take it back and send something else.
 
RustyRatRod said:
The milder the engine, the more vacuum it creates. As I said, I would put that carb back stock and send it back. If you got it from Summit, they will gladly take it back and send something else.
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So you're pretty confident I have an underlying issue somewhere?
 
Also I just took a peak at Summit they won't accept returns 6 months after the purchase date :(
 

jmanhoff said:
So you're pretty confident I have an underlying issue somewhere?
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It certainly seems that way. I had one of those exact carburetors I bought new. Couldn't get it to idle. It ended up having an internal vacuum leak. I sent it back. Summit refunded my money. A few months later, I "cautiously" got another one, because my truck needed a carburetor and I liked the idea of those. I ran it for about a year and then got what I really wanted on it, a Street demon 750. I still have the Brawler 650. It ran really good, but it just was not enough. I have a pretty warm 400 Ford engine in a 75 F250. That's a HEAVY truck and it needs some carburetor. Now my 650 sits in my cabinet waiting on "whatever" I might put it on next.
 
jmanhoff said:
Also I just took a peak at Summit they won't accept returns 6 months after the purchase date :(
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I would still call them. Quick Fuel used to offer a lifetime warranty. It's worth a call.
 
RustyRatRod said:
I would still call them. Quick Fuel used to offer a lifetime warranty. It's worth a call.
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I'll see what they're willing to do. I would've gotten a Holley but the $200 wasn't QUITE in the budget at the moment. Though from what I've read the difference really doesn't seem to be really big. Currently the truck is my daily so I can't just wait 2 weeks to return and get a replacement carb in so I guess I'll have to stick it out for now. Maybe I can use this time to poke around on the inside and get hands on with how all the circuits work.
 
So obviously in order to get all the actual nozzle and jet sizes I'd need a pin gauge set. Would a 0.011-0.060 set be suffice? Theres really two that I can see, the M0 which seems to be as mentioned, then a M1 which is 0.061-.250. Or could I use the numbers stamped on any of the parts that have holes larger than 0.060"? I'd imagine since they setup the carbs to flow XYZ they would just use a different part and not drill it in the factory so the part numbers should be accurate?
 
Newbomb Turk said:
Depending on how big your main air bleed is, you could be cruising on the main jet at 2800. If you are on the booster at 2800 then you need to drop the primary main jet to get the cruise AFR where it needs to be.

If you are still on the T slots, I'd drop down to .048ish. If you get on the lean side of it the next time you swap in some brass you can always just pull them back out and open them up a bit. It's easier to drill out one set (if you can) than to keep using new brass to go smaller.

Soooooooooooo...if no one has told you how this works I'll give it a shot.

On a Holley or Holley clone, you need to set your cruise AFR with the T slots at low throttle openings and the primary main jet for higher throttle openings. So you have to sort out if you are cruising on the PMJ or the T slot and tune on one at a time.

To that end, to tune for WOT after you have the T slots and PMJ sorted out you only change the secondary main jet OR the power valve channel restrictors. Once you have the cruise AFR ironed out you never touch the PMJ again.

If for some reason you need to fatten up WOT a bit you open up the PVCR on the primary side and add main jet on the secondary.

Again, cruising down the freeway at 70 you are on the booster (which is another way of saying you are on the PMJ) so yo would adjust that and get it correct.

And you have already cleaned up your transition and T slot AFR.

Once you have that sorted out you can go to tuning for WOT. If your cruise AFR is where it should be, you don't touch your T slot restrictors or the PMJ. You change WOT with your PVCR's and the SMJ.

This of course leads to unscrewing the power valve timing issue.

The power valve cold have been named the economizer valve because that's really what it does. It allows us to run a very lean and crisp, clean cruise on the PMJ and then as you get further into the throttle and vacuum starts dropping the power valve opens and adds extra fuel. It really is two small jets behind the power valve. They work like main jets but they only add fuel when manifold vacuum drops below whatever your power valve is rated at.

A 2.5 power valve will open significantly later than an 8.5 for example.

Holley says (and so do many others but they are wrong) to set your power valve opening point at half your idle vacuum. If you have 14 inches of vacuum at idle they'd say use a 6.5 to start. And that's probably not close.

I use about 75% of CRUISE vacuum to start with and tune from there. If you have 18 inches at a cruise then I'd start tuning with a 10.5 because that's all you can get in that range. If I could get a 12.5 I'd start with that.

The thing to remember about the power valve is it tunes two ways.

One is off manifold vacuum (when it opens and shuts as the vacuum goes up and down with load and RPM) and the other is with the restrictors.

The rating (8.5 or 4.5 etc.) sets at what manifold vacuum it opens (which is really the start point that it adds fuel) and those little restrictors control how much fuel you are adding. And any change you make to the PV is always separate from the primary main jet. You can change the opening point (which will add fuel sooner or later) and then change how much fuel you are adding at WOT.

You can find some nice little power gains but more importantly you can trim the fuel curve right up and get EFI like fuel consumption and drivability if you learn to tune.

I hope this makes some sense.
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So I've been reading the threads that were posted earlier and came across this post and wanted to verify that I was understanding this correctly in terms of the PV.

So theoretically, say I go down to the 64 PMJs, and run a 10.5PV, or even a 12.5PV if I ran the alcohol ones? If the motor runs fine at light throttle (T-slot to booster) on the 64s and when I need a little more power and I put my foot down, would the sooner opening PV help with the lean surging or do I need to just stick with the 66s?

Basically, the 64s, at least how the carb sits right now without messing with anything else internally, are the smallest jets I can run before I'd imagine I'd see the plugs too lean. (I believe I posted the plugs with 66s in this forum way back when, and someone said I could probably go a touch leaner), so would a numerically higher PV potentially fill this lack of fuel?
 
jmanhoff said:
So I've been reading the threads that were posted earlier and came across this post and wanted to verify that I was understanding this correctly in terms of the PV.

So theoretically, say I go down to the 64 PMJs, and run a 10.5PV, or even a 12.5PV if I ran the alcohol ones? If the motor runs fine at light throttle (T-slot to booster) on the 64s and when I need a little more power and I put my foot down, would the sooner opening PV help with the lean surging or do I need to just stick with the 66s?

Basically, the 64s, at least how the carb sits right now without messing with anything else internally, are the smallest jets I can run before I'd imagine I'd see the plugs too lean. (I believe I posted the plugs with 66s in this forum way back when, and someone said I could probably go a touch leaner), so would a numerically higher PV potentially fill this lack of fuel?
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All that is assuming the carburetor hasn't a defect. I believe it has. I think if you continue on your path with this particular carburetor, you won't have success. The reason I say all this is because that carburetor should have been just about a DEAD match for your engine pretty much out of the box. It wasn't.
 
jmanhoff said:
I’m assuming by idle and t slot tuning you mean in the metering block? I plan to graph out the timing soon once I get everything situated.

It’s a manual, if it matters it’s the stock flywheel and clutch setup you would find on a manual 5.9 gas 1500

I may order the pump cam set but I think I should at least pin out every hole in this carb and get that data posted first before I do anything like that
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If it's a manual then you'll want that power valve to open maybe three inches below what your idle vac
 
The way to turn the primary is to cruise at 55+mph for the test and you lean out the primary until it starts to lean surge then you go back up two Jet sizes. Typically the carb is fine with the secondary jetting it comes with out of the box, you're just tuning your transition with shooters or cams and power valve. So will the manual I usually go a couple inches below whatever my neutral idle vacuum is and I try to use just enough shooter and typically the red Cam. I get away with 31 Shooters but on my typical 750 Holley double pumper I used to run.. #28 shooters worked.
I'm currently running a speed demon 750 double pumper and it likes the 31s. It also wanted three Jets taken out of the primary down to 73. So I have it set up at 73/83 as opposed to 76/83.
 
RustyRatRod said:
All that is assuming the carburetor hasn't a defect. I believe it has. I think if you continue on your path with this particular carburetor, you won't have success. The reason I say all this is because that carburetor should have been just about a DEAD match for your engine pretty much out of the box. It wasn't.
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I wonder what the defect could be then? I’ll email summit and see what they say. It’s weird how the 66 PMJ with the 9.5PV makes the engine the happiest at least while it’s moving, getting moving has always been an issue but I’ve been getting around that by just blipping the throttle a couple of times before I let out the clutch.
 
MOPAROFFICIAL said:
The way to turn the primary is to cruise at 55+mph for the test and you lean out the primary until it starts to lean surge then you go back up two Jet sizes. Typically the carb is fine with the secondary jetting it comes with out of the box, you're just tuning your transition with shooters or cams and power valve. So will the manual I usually go a couple inches below whatever my neutral idle vacuum is and I try to use just enough shooter and typically the red Cam. I get away with 31 Shooters but on my typical 750 Holley double pumper I used to run.. #28 shooters worked.
I'm currently running a speed demon 750 double pumper and it likes the 31s. It also wanted three Jets taken out of the primary down to 73. So I have it set up at 73/83 as opposed to 76/83.
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Would those higher vacuum PVs work then even though they’re “not for gasoline”?
 
jmanhoff said:
I think I would blow apart my tranny and rear diff before I could burn the tires that much lmao. 200k original tranny and 8.25, I know the 8.25 is a proven axle but at 200k it’s probably not up for the task anymore. Plus the AX-15 tranny from 1992 is only “rated for 300ftlbs at the crank” and watching a video of an almost identical setup of my engine making 410ftlbs I think I’m just a little outside its rating
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Just trying to save you from 9 more pages of frustration.
You have already futzed with that thing more than a British motorcycle, and you haven't even got into pump cams, or nozzles yet. :p
 
Johnny Dart said:
Just trying to save you from 9 more pages of frustration.
You have already futzed with that thing more than a British motorcycle, and you haven't even got into pump cams, or nozzles yet. :p
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Lol I’m also just a really stubborn traditionalist because my dad grew up with mopars and holleys so I’m kind of just following the same road.
 
jmanhoff said:
I wonder what the defect could be then? I’ll email summit and see what they say. It’s weird how the 66 PMJ with the 9.5PV makes the engine the happiest at least while it’s moving, getting moving has always been an issue but I’ve been getting around that by just blipping the throttle a couple of times before I let out the clutch.
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Ok. Have fun. I'm tired of giving advice. I recommended you CALL THEM. A frakkin email ain't gonna get results. Wallow in it.
 
Too much text... Pull the carb off, take it apart and take some pics of what you got then upload them here.
 
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