Firecore ZOOM ZOOM!

[myk]

But in the meantime, I use the Holley parts to tune the Proform?

[don duick]

to back up what Ghoste said , I had a edelbrock carb when my 440 was stock and it ran fine. I rebuilt my 440 and now has 400 hp using a 750 holley vac sec. I tried the edelbrock carb out of curiosity and I noticed a loss of power.

[pipeliner]

What about the quickfuel carbs? I heard they were hard to beat.

[303 Mopar]

What about the quickfuel carbs? I heard they were hard to beat.

Quickfuel's are excellent.  Had a 780 QF on my 408 stroker.  Seems like they became popular and the price the shot up.  You can get a comparable Proform for less.

[myk]

Yeah I'm looking at the Proform 750 now.  Ron says that the fuel curve on the Eddy's is just too lean or something.  I'm tempted to get a smaller 'carb though?  All of the online CFM calculators and anyone in my neighborhood that wrenches for a living are telling me to go smaller; like a 650 or around there...

[pipeliner]

I hate to sound ignorant but I've never heard of a proform. I'll look em up.

[myk]

You're not the only one brother.  I've just started learning about them as well.  From what I gather they're Holley clones with some tweaks for even more adjustability and better quality control.  Personally, I'm worried I'll get lost with all of the fine tuning but whatever...

PS: their starters suck

[303 Mopar]

Yeah I'm looking at the Proform 750 now.  Ron says that the fuel curve on the Eddy's is just too lean or something.  I'm tempted to get a smaller 'carb though?  All of the online CFM calculators and anyone in my neighborhood that wrenches for a living are telling me to go smaller; like a 650 or around there...

I think the CFM calculators are close but I always round up.  I was leaning toward an 850 cfm for my 440, but it pretty tame and Ron talked me into the 750.  I have not had a chance to put everything on       but plan to in the next week or so.

[don duick]

Yeah I'm looking at the Proform 750 now.  Ron says that the fuel curve on the Eddy's is just too lean or something.  I'm tempted to get a smaller 'carb though?  All of the online CFM calculators and anyone in my neighborhood that wrenches for a living are telling me to go smaller; like a 650 or around there...

the intake of A 650 carb will not match the output of your new headers.

[BSB67]

Yeah I'm looking at the Proform 750 now.  Ron says that the fuel curve on the Eddy's is just too lean or something.  I'm tempted to get a smaller 'carb though?  All of the online CFM calculators and anyone in my neighborhood that wrenches for a living are telling me to go smaller; like a 650 or around there...

Stick with what Ron is telling you.

[1974dodgecharger]

Yeah I'm looking at the Proform 750 now.  Ron says that the fuel curve on the Eddy's is just too lean or something.  I'm tempted to get a smaller 'carb though?  All of the online CFM calculators and anyone in my neighborhood that wrenches for a living are telling me to go smaller; like a 650 or around there...

YUP, edelbrocks are too lean, but they lean to get good MPG 

Proform, quickfuel, etc.. all those guys are YES clones of HOlleys, but where Holley didn't upgrade those guys did.  Then HOlley finally upgraded their stuff to follow suit....like I said eventually HOlley will buy out profrom, quickfuel, etc....they always do 

[myk]

Nothing like sticking your head into a 2800 RPM screaming engine on a 90* plus day with no shade to experiment with timing. 

So now I've got 24* of initial and 13* of mechanical advance, all in by 2500 RPM.  The initial is crazy high in my experience but, like Ron and everyone else said, set it for 'max vacuum.  Adjusting the mechanical advance on the Firecore distributor was pretty easy also, once I figured out how to do it.  I also messed with the idle mix screws, found out they were WAY unbalanced and adjusted them for 'max vacuum.  All in all it's pulling 18-19 inches of vacuum at 850 RPM idle speed.  I'm guessing I have a 'cam for a Prius in there?  Car is running better for what it is, though...

[myk]

Ok just got back from a car meet and the car is definitely running hotter.  I take it this is because of the 24* of initial?  So what am I supposed to do?  The car responded very well to the 24* of initial, dictated by the highest vacuum reading, but if the motor is going to melt itself into hell it's not going to work out.  Do I revert back to my initial setting of 18/19* of initial, or improve my cooling set up if I want the 24* of initial?  Is it one or the other, or can I have both?   

[Stegs]

The Eddy/Carter carbs are fine, they just are a lot more limited as to what can be changed for tuning without getting into actual surgery.  If you want to bolt it on and forget about it, they are a good choice.  If you want to go looking for power though, then the Holley style becomes the best choice.
The Proform takes it a step further Myk by adding some tuning parameters not available in most of the Holley carbs.  Some of the internal passages are also different I believe and the quality control is higher as well.

but for 120 dollars more, are the proforms that much better than a holley 4160?

If you had a cruiser like myself, never will see any track times, or street racing.....is the 120ish dollars worth it?

I could see if it was a race motor and you needed all the adjustability you can get...but for a cruiser 440?

[myk]

I think we'd both be fine with a Holley 4160, but personally I plan to relentlessly tinker with the car and possibly auto-X it so the extra tuning capability might be necessary...

[firefighter3931]

Ok just got back from a car meet and the car is definitely running hotter.  I take it this is because of the 24* of initial?  So what am I supposed to do?  The car responded very well to the 24* of initial, dictated by the highest vacuum reading, but if the motor is going to melt itself into hell it's not going to work out.  Do I revert back to my initial setting of 18/19* of initial, or improve my cooling set up if I want the 24* of initial?  Is it one or the other, or can I have both?   

Myk,

The timing adjustment leaned out the mixture....it needs more fuel. 

This is where a good carb with nice & easy tuning features comes in handy 

Does it feel more responsive with the additional base timing ?



Ron

[myk]

Ok just got back from a car meet and the car is definitely running hotter.  I take it this is because of the 24* of initial?  So what am I supposed to do?  The car responded very well to the 24* of initial, dictated by the highest vacuum reading, but if the motor is going to melt itself into hell it's not going to work out.  Do I revert back to my initial setting of 18/19* of initial, or improve my cooling set up if I want the 24* of initial?  Is it one or the other, or can I have both?   

Myk,

The timing adjustment leaned out the mixture....it needs more fuel. 

This is where a good carb with nice & easy tuning features comes in handy 

Does it feel more responsive with the additional base timing ?



Ron

Yes, the car is more responsive with more initial.  It was good when I was just running 18* of initial but it liked the additional timing so I fed it until highest vacuum was reached.  So are we talking about richening the idle mixture or is this about jets and needles too? 

I was reading that having timing that's too retarded is also very bad for motors, something about the combustion process being adversely affected.  How do I know if im reaching that point, without looking for glowing hot headers or boil overs?

[Stegs]

I think we'd both be fine with a Holley 4160, but personally I plan to relentlessly tinker with the car and possibly auto-X it so the extra tuning capability might be necessary...

I ordered a holley 4160 this morning. 750, electric choke, vac secondaries

to have all the fine tuning capabilities is nice, but for someone like myself who just wants to cruise out to the beach ....i want to bolt on and go....

[myk]

I think we'd both be fine with a Holley 4160, but personally I plan to relentlessly tinker with the car and possibly auto-X it so the extra tuning capability might be necessary...

I ordered a holley 4160 this morning. 750, electric choke, vac secondaries

to have all the fine tuning capabilities is nice, but for someone like myself who just wants to cruise out to the beach ....i want to bolt on and go....

I completely understand.  We need to start reading up on Holley tuning and adjusting, though.  There are quite a few books and videos floating around to help...

[c00nhunterjoe]

Fine tuning a holley is nothing more then a little patience, plug reading, and a few extra spare parts to buy. You should be able to tune it in a couple hours and have it crisp and responsive. The only "major" parts you should need to change on a mild street engine is jets, accel pump squirters and possibly cams. All are done with a small screwdriver and 1/4" ratchet set. Was it possible to order that 4160 with 50cc pumps? A wise upgrade on even a mildly cammed big block.

[firefighter3931]

Yes, the car is more responsive with more initial.  It was good when I was just running 18* of initial but it liked the additional timing so I fed it until highest vacuum was reached.  So are we talking about richening the idle mixture or is this about jets and needles too? 

I was reading that having timing that's too retarded is also very bad for motors, something about the combustion process being adversely affected.  How do I know if im reaching that point, without looking for glowing hot headers or boil overs?

Myk,

It most likely needs more fuel on the main jetting....not the idle circuit. Increased timing requires more fuel to maintain the correct A/F ratio. 

Timing that is retarded can cause overheating ; this occurs when the fuel is not burned in the combustion chamber. If the timing is late..... unburnt fuel will ignite in the manifold/header and create a lot of exhaust heat.

Two different things that can lead to the same outcome. 

In your case the timing is not retarded so I'm leaning towards a lean main circuit in the carburetor 



Ron

[myk]

Ron thanks for getting back to me.  I will go up a size in primary jets and maybe the needles too.  I guess I can leave the secondaries alone?   The car runs cool until I get into traffic, then I start seeing 230 or so.  What is it they say?  If you heat up on the freeway its an airflow problem, if you heat up in traffic its a coolant flow problem?  Regardless, I want to keep the timing settings.

I'm installing a milidon water pump and that aluminum radiator from Engineered cooling products from eBay as well...

[303 Mopar]

Ron thanks for getting back to me.  I will go up a size in primary jets and maybe the needles too.  I guess I can leave the secondaries alone?   The car runs cool until I get into traffic, then I start seeing 230 or so.  What is it they say?  If you heat up on the freeway its an airflow problem, if you heat up in traffic its a coolant flow problem?  Regardless, I want to keep the timing settings.

I'm installing a milidon water pump and that aluminum radiator from Engineered cooling products from eBay as well...

Hey Myk,
Did you ever get the jets changed?  How hot is she running now?

[myk]

You know, I never got around to the jets.  After installing the aluminum radiator that Bryan talked me into, as well as the Milidon water pump that Ron suggested, and the Hayden/Jaguar clutch Dino mentioned, the car runs so cool, TOO COOL in fact, that I'm actually looking into a hotter t-stat to get her running warmer more consistently.  As she is now, I get 140-160* on the freeway and 180-200* in traffic.  I am also about to pull the trigger on a new Pro-form or Holley 4160 'carb so tuning the 'Eddy seems pointless to me...

[303 Mopar]

You know, I never got around to the jets.  After installing the aluminum radiator that Bryan talked me into, as well as the Milidon water pump that Ron suggested, and the Hayden/Jaguar clutch Dino mentioned, the car runs so cool, TOO COOL in fact, that I'm actually looking into a hotter t-stat to get her running warmer more consistently.  As she is now, I get 140-160* on the freeway and 180-200* in traffic.  I am also about to pull the trigger on a new Pro-form or Holley 4160 'carb so tuning the 'Eddy seems pointless to me...

Nice!  I just put on a Proform 750 and LOVE IT!