Ristow's Holley 4548 vs. My Edelbrock 1405 Shoot-Out

[Billygoat]

I'll throw out there that your Edelbrock is too much carb. You have the 1405 600cfm compared to the 4548 450 cfm Holley.
I went from a 1405 to a 1404 (500 cfm) on my 360 in my CJ and I saw a lot of the driveability changes you are seeing - including the sound change.
I know your test is limited to what you have (I sold my 1404 years ago or I would offer it to test), but everyone should keep that in mind.
Despite what the carb companies tell you, there is such a thing as too much carb - for the street anyway.

The felxability in the tuneability on the Holley vs Edl is a fair comparison, no difference in that on from the 1405 and 1404, so that is great to see.
And I will say I am a Edl fan, only because I am familiar with them, but I really like what I see on the Holley, might have to give one a shot sometime.

[sld]

http://www.carcraft.com/techarticles/selecting_right_carb/index.html

[rreed]

Yes it's correct that for my application a 600 CFM carb is way too much. We've learned that recently: http://www.ifsja.org/forums/vb/showthread.php?t=154201 Heck for my application a 2V might even suffice (until I need some ba**s to get around some slow poke slower than me ), and maybe some day I'll pick up a 4V to 2V adapter and blow the dust off the Holley 2V I have in a box on my shelf. That is yet another experiment on my list. I don't recall if I've indicated that this is a comparison b/t a 600 CFM and 450 CFM carb, I'd have to look but need to get back to work.

I don't think the Edelbrock is a "bad" carb per se (oh great, we just lost Ristow and addicted, haha). It's exceedingly simple to work on and tune. I don't think it's a terrible performer and though you may not be able to get as granular and precise as a Holley, it still gets you pretty close. I have no complaints on mine except for when it was on the SBC in my CJ-5 (bought it that way) you couldn't wheel more than a parking lot w/ it. I'm just finding that there are things about the Holley that are better, especially when you like to tinker and really tune. For the average Joe who just wants to slap down a decent performing carb w/ minimal adjustment and fuss, well you should probably just get a hold of Ristow. Otherwise, the E's are probably good enough to get a generally good running motor and be on your way.

But if you want really good performance and potentially better mileage for similar if not better performance (again, w/ an empty truck this thing is doing as well if not better than the larger Edelbrock it's temporarily replacing) go w/ the Holley. Especially if you like to fine tune, tinker, and perfect your running engine. There is probably a good reason why you found a heck of a lot more Holleys on old 60s and 70s era muscle cars than you did Carter AFBs.

I didn't think I'd like not having control over the secondaries in a vacuum secondary carb but if this thing shows better mileage than my mechanical secondary Edelbrock, I'll be completely sold. The secondaries on this Holley are so seamless compared to my Edelbrock. It's not a bad thing that it's more noticeable on the E, just nicer on the Holley.

Oh, there are some things I keep forgetting to mention about the secondaries on my particular Edelbrock that might offend those who've been reading up to this point, but more on that later. Again, this will be a before, after, after comparison. There are some things that I do need to correct on my Edelbrock to be fair in the end; I need to go up one size or so on the secondary jets on my E. I kept forgetting to mention that, sorry. More later though to clarify, but back to work.

[serehill]

I have to say

My findings are much the same I did lose just a little off the top of the power range but not much. Going from 750 to 600 speaks volumes about that if I only lost a little that's impressive. Yes maybe it was an apples to oranges comparison but the mannerisms of the holley doesn't have anything to do with that. The difference is towards the good for the Holley in my test it is more refined. I see a dramatic improvement in mileage. I don't hate Edlebrock or thier owners but I Like the refined improvements. The Holley is my carb of choice now.

[rreed]

Billygoat, what carb are you running now? Comparison/results to your two Edelbarfs?

Serehill, I'm wondering if when you went from 750 to 600 CFM and didn't see a dramatic difference, were you really using that much of the 750 to begin w/? Just a rhetorical pontification.

FWIW, before I filled it up yesterday it was around half the tank Edelbrock, then half farting around w/ this Holley and a certain amount of jacka**ing around w/ the skinny pedal and I got around 10.5 MPG vs. if it was a complete tank of just the Edelbrock I would have to drive like a complete saint to get 11 MPG out of it. I dunno, we'll know more around Monday/Tuesday what kind of mileage I'm getting w/ the first tank keeping my "Edelbrock" driving style. It might be important to note that this Holley is way more tolerant of high gear/low speed grunt so after this tank of gas I'll drive it more to torque, meaning I'll be leaving it in top gear a lot more at low speeds (intersections, parking lots, etc.) and shifting at much lower RPM during acceleration. I've already been experimenting w/ different shift points' affect on mileage but this will not interfere. Will report on that in another thread when that experiment is done.

Back to my Edelbrock's secondaries, one of the reasons I stay out of them w/ mine (besides fuel consumption and lack of real "need" w/ an empty truck in my case) is because I think the stock jetting for them is too lean. I did have to go up one stage rich on the primaries (simple rod change) to cure a lean/over heating at highway speeds/white ashen plugs. When I get into the secondaries, at any RPM in any gear, stabbing the throttle or even just slowly pushing through it, it will either bog or just outright pop and back fire through the carb. I believe my accelerator pump to be okay because at any RPM/speed/gear I can poke and stab at the pedal--w/o getting into the secondaries, just using primaries--it jumps right up and takes off. No bog, no flat spot, no back firing, it just hops up, the front end comes right up, and away she goes. I understand that to be a good accelerator pump setup. But no matter if you stab it to the floor or just slowly push all the way through to the bottom to hit the four-barrel, once that secondary "firmness" in the pedal is felt and the "growl" is heard under the hood it falls on its face and often will pop and sputter. Given all this I just ordered the next size bigger jets for the secondaries. After we're done trying out Ristow's Holley my Edelbrock will go through a little more tuning for and after-after comparison for performance (regarding secondaries and driving stupid). I could be way off here, anyone is very welcome to correct me. The jets were only $8.

Also picked up 4" enrichment springs for my Edelbrock. Stock springs are supposed to be 5" and if my on-board vacuum gauge is accurate I feel it has plenty of grunt down to 4" before it needs that extra enrichment whether empty or pulling something relatively heavy.

[Billygoat]

The CJ is long gone, and on the 2 FSJ I am running TBI, and they went from the stock 2150 to the TBI.

On the CJ I actually took the secondary linkage off, and only missed it when I forgot to connect it well towing a heavy load (probably more than I should have pulled with a CJ anyway). The CJ went to TBI after the Edl, and I will say other than minor improvements, the biggest advantage what starting.
When I traded the CJ I put the rebuilt 2150 off the J20 on it with a 2bbl to 4bbl adapter on the preformer intake (swapped the TBI onto the J20) I drove it very little after that, the most being the trip to trade it off, but I did notice it was lackluster with the 2150, but that was pretty much a slap on and get it to move under it's own power installation.

If (no make that when ) I get another FSJ I'll probably keep it carb'd, I like TBI, and the computer control tinkering, but I look back on memories I had learning about trucks with my J4000 with it's carb and points, and have to say, old tech is still good tech, the principles of tuning are still the same, you just adjust thing mechanically, instead of electronically.

[serehill]

There's no doubt

Billygoat, what carb are you running now? Comparison/results to your two Edelbarfs?

Serehill, I'm wondering if when you went from 750 to 600 CFM and didn't see a dramatic difference, were you really using that much of the 750 to begin w/? Just a rhetorical pontification.

FWIW, before I filled it up yesterday it was around half the tank Edelbrock, then half farting around w/ this Holley and a certain amount of jacka**ing around w/ the skinny pedal and I got around 10.5 MPG vs. if it was a complete tank of just the Edelbrock I would have to drive like a complete saint to get 11 MPG out of it. I dunno, we'll know more around Monday/Tuesday what kind of mileage I'm getting w/ the first tank keeping my "Edelbrock" driving style. It might be important to note that this Holley is way more tolerant of high gear/low speed grunt so after this tank of gas I'll drive it more to torque, meaning I'll be leaving it in top gear a lot more at low speeds (intersections, parking lots, etc.) and shifting at much lower RPM during acceleration. I've already been experimenting w/ different shift points' affect on mileage but this will not interfere. Will report on that in another thread when that experiment is done.

Back to my Edelbrock's secondaries, one of the reasons I stay out of them w/ mine (besides fuel consumption and lack of real "need" w/ an empty truck in my case) is because I think the stock jetting for them is too lean. I did have to go up one stage rich on the primaries (simple rod change) to cure a lean/over heating at highway speeds/white ashen plugs. When I get into the secondaries, at any RPM in any gear, stabbing the throttle or even just slowly pushing through it, it will either bog or just outright pop and back fire through the carb. I believe my accelerator pump to be okay because at any RPM/speed/gear I can poke and stab at the pedal--w/o getting into the secondaries, just using primaries--it jumps right up and takes off. No bog, no flat spot, no back firing, it just hops up, the front end comes right up, and away she goes. I understand that to be a good accelerator pump setup. But no matter if you stab it to the floor or just slowly push all the way through to the bottom to hit the four-barrel, once that secondary "firmness" in the pedal is felt and the "growl" is heard under the hood it falls on its face and often will pop and sputter. Given all this I just ordered the next size bigger jets for the secondaries. After we're done trying out Ristow's Holley my Edelbrock will go through a little more tuning for and after-after comparison for performance (regarding secondaries and driving stupid). I could be way off here, anyone is very welcome to correct me. The jets were only $8.

Also picked up 4" enrichment springs for my Edelbrock. Stock springs are supposed to be 5" and if my on-board vacuum gauge is accurate I feel it has plenty of grunt down to 4" before it needs that extra enrichment whether empty or pulling something relatively heavy.

The 750 was too big. I went to a 650 1406 then to the 4180/ 600CFM. The 750 was more powerful but a hog. It was too much. It still out performed the holley but not by much I'm running a mild cam Full MSD system & headers. I'll never be a Edlebrock hater because they clearly have their place. I like the smoothness of the 4180. It wasn't far off the minute I put it on. My high idle is a little high but that's only because I'm lazy. I think they both have their places but I can't claim one is inferior for everyone.

[Ristow]

Mom's talking up a storm,he's nodding his head and saying "um-hmm" but he's thinking about secondary springs,shift points,roll on throttle response and fuel mileage.

[rreed]

Haha, that's exactly what was happening!!

Back to work this morning. I really hate that choke. Whatever, I just make sure there are no cars coming when I whip her out on the main drag.

Double-checked my VA, it's close enough at around 7.5-ish or so. Hooked up my hand-held teed in w/ the on-board vacuum gauge to double-check for accuracy, they're both accurate to each other so hope that means something.

I'm going to throw in my gas can tomorrow, the gas gauge is starting to make me a little nervous. I'm awful used to it looking more like a metronome during the week b/t fill ups. I wasn't sure it was even moving this morning until a little closer to the office. I'm not convinced it can't have coincidentally broken during this carb experiment. I should have had to fill up by now.

Say Ristow, which spring did you mention was in the secondary pot? I'm wondering for reference so when I'm heading up the road I'll know vaguely when they start kicking in.

[Ristow]

pretty sure it has the neutral spring (not colored) which as memory serves is the middle of the range. i'll be putting a black (stiffest) spring in it,which will delay the opening of the secondaries.

[rreed]

Cool. Does that translate into hG or is it more of a time-delay thing?

[Ristow]

the stiffer the spring the more vacuum needed,which equates to a higher velocity thru the primaries need.

you can tailor the opening rate with these springs obviously. for a daily driver i like em to come in late. you can also tailor the speed a bit by removing the check ball that is under the cover. some don't utilise that however, and simply use an orifice.

[rreed]

Magic, got it.

[rreed]

I threw in my gas can this morning, not ruling out that gauge didn't coincidentally start flaking out. I think i'm pushing 175+ miles and just hitting E (which means i have 4-5 gal. left because of the skewed gas gauge) when i would normally be at 150-160 miles w about 4-5 gal. left. I'll take a closer look at lunch and will fill up on the way home for an accurate count. Just by days driven to work alone i would have been filling up on the way in this morning but the gauge says i still have plenty left. Spooky and scary.

I HATE that !@#$% choke.

[jdaniel83]

I HATE that !@#$% choke.

Just out of curiosity what about the choke do you not like?