FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: My427stang on May 23, 2020, 02:19:37 PM
-
Jay, years ago I remember you and Royce testing a bunch of carb combos. If it's in your book....just send me to go read it, I have it LOL However, if not, do you have those results somewhere?
I am looking for what the dual 450s did, what bigger carbs did, and what you tested them on. Even better would be any fighting you did with the fuel curve on any of the combos.
I am specifically asking for a 550-ish HP stroker, and trying to compare apples to different apples :)
Thanks
-
Ask, and you shall receive, Ross ;D ;D
In the book, the carb comparison data is on pages 223-226, charts are on pages 225 and 226. There is only one chart for a 2X4 setup, and it is a lower HP engine. However, a few years back I dynoed a 390 stroker for a friend of mine that had stock Edelbrock heads, a small solid roller cam, one of my intake adapters and a Weiand tunnel ram. My friend was convinced that the 450 carbs would be the way to go, so he had some worked over by a local carb guy and brought those. After we dynoed with those the results were disappointing, so I swapped on my set of 660s and we ran again. The results are in the chart below; it was a big difference. Unfortunately I don't have any data on what jets we used, but there were several runs with the 660s on the dyno, and the A/F numbers started out lean, but gradually came in, so I assume we were doing jetting changes along the way. Hope this helps - Jay
(http://fepower.net/Photos/Posts/450vs660_1.JPG)
-
This whole "smaller 2x4 carbs=better" scenario has been a source of annoyance more than once for me.
Ford in their inifinite funding, decided on two 600's for their street 427, later they used dual 715's. Now guys are building 482ci strokers and asking me about dual 390's or 450's because of some stupid Holley calculator. Lol..... right right right. The Holley calculator has one purpose, and it is to keep annoying people from calling the apathetic help line.
When asked, I'm sticking to my guns here:
>550hp dual 600's
>550hp more race oriented, dual 715's
<550hp street, dual 715's
<550 full race, 660's
Big cubes, big power street, dual 780's
If you are a tinkerer, you can blur those lines a good bit more.
The one place I like to use 1848's, 1849's or -C carbs is for the 390/410 mild cruiser that just wants the glam of 2x4's.
I am curious about dual 850cs's vs 660's with much larger (500ci + full race) engines, I just don't have any real track data for that.
-
You will be happy to know that I plan to test 660s vs the center squirter 850s you did for me a while back, when I get my dyno engine back on the pump to test my cylinder heads. Should be an interesting comparison...
-
You will be happy to know that I plan to test 660s vs the center squirter 850s you did for me a while back, when I get my dyno engine back on the pump to test my cylinder heads. Should be an interesting comparison...
Test dual 1050 Dominators and the rest won't really matter.... :)
-
You will be happy to know that I plan to test 660s vs the center squirter 850s you did for me a while back, when I get my dyno engine back on the pump to test my cylinder heads. Should be an interesting comparison...
Test dual 1050 Dominators and the rest won't really matter.... :)
Or 1450's.....
(https://live.staticflickr.com/65535/49596832256_ee82ed6df6_c.jpg)
To follow Drew's discussion, I use a lot of the 725cfm carbs on the FE 2x4 setups. They will support 725 hp easily.
-
Sorry for the 2nd post on this, but.
I was amazed 50 years ago at what Smokey was doing but that thing he dreamed up is unbelievable now and that was a long time ago.
-
To follow Drew's discussion, I use a lot of the 725cfm carbs on the FE 2x4 setups. They will support 725 hp easily.
Once you get into dual Dominators, it is really a whole nother engine with a vastly different purpose.
Regarding the 715/725, I really wish Holley had made a ton of 1 5/16, 1 3/8 venturi, 1 11/16 throttle bore generic downleg carbs. I find them to be a very good size. Seems like they went from 600’s right to 750’s with slim pickings in between (for VS)
-
You will be happy to know that I plan to test 660s vs the center squirter 850s you did for me a while back, when I get my dyno engine back on the pump to test my cylinder heads. Should be an interesting comparison...
I kinda have the view that bigger carbs will generally make more dyno power. Nice to test them in a car.
I have considered making a set of 4160 850 cs’s for my own tests, but I really don’t have enough engine.
-
I believe drew has the correct statement as far as 450s vs 660s vs ect.
If you have enough engine! Most fe engines built today are, as dont see alot of 352 stock builds with duals. 450s worked great for my (mexican block/cleveland head) boss 302. Ya oops, 16 yrs old with 1978 technology also. hahaha
-
All I can add is my 660's that had the 850 mods done to them are marginally quicker than my 600 QF Vacuum carbs. (2x4) Tried them both on my old 427 and the current 428 with the same result. Both are high 9 second engines so it seems like a fair observation. Fuel mileage does suffer badly with the 660's. People waaaay… smarter than me have suggested a too big carb can look good on a Dyno but not go down the track well. One only has to look at the power a Super Stock engine can make with a factory sized carb. Pretty sure Blair can elaborate.
-
Thanks!
I have used a few of the mechanical 450s, but they were on nearly stock CJs, a CJ spec 410s, and the largest was a 282S cammed medium riser 454, they worked great but never dyno'd. These are repop 1848 465 vac secondaries made to look like original Ford, but essentially the same carb in terms of airflow I believe.
I am going to try a set of Drew's big carbs, and we'll run the 465s, and if it makes sense to do so, I will spin up a pair of 1850-2 600 mongrels I have to split the middle. I'll let you know my dyno results to add to the list.
I really appreciate it, and it certainly looks like it's worth the time to try them
-
Jay, years ago I remember you and Royce testing a bunch of carb combos. If it's in your book....just send me to go read it, I have it LOL However, if not, do you have those results somewhere?
I am looking for what the dual 450s did, what bigger carbs did, and what you tested them on. Even better would be any fighting you did with the fuel curve on any of the combos.
I am specifically asking for a 550-ish HP stroker, and trying to compare apples to different apples :)
Thanks
I seem to remember some fiddling around with a 3 barrel Holley in the carb flogging. Can you elaborate on some of the ancient "big" Holley mess'n?
-
>This whole "smaller 2x4 carbs=better" scenario has been a source of annoyance more than once for me.
LOL. "1200 CFM is too much for a 302!" says the internet and Facebook. I was just able to get out Sunday and test the Falcon with the new Meziere water pump and fabbed alternator mount. Along with the dual Holley 600s with some tweaks (from racing fuel systems discussion) on the tunnel ram. Both List 1850s, eBay specials. This is a 351C, stock stroke, 30 over, decent hydro roller, 10.5:1 4V closed iron heads, 4.56 gears, 4500 stall 10" converter. Only had some 87 octane fuel, 2 gallons in the cell so it was once around the block. I gave it a good punch just because and the thing jumped up in the air like it wanted to fly. 2500 to 5K+ in a blink. Will track test it with a LC2 datalogger and the proper VP110 mix at the TnT on 6/6. But the butt-o-meter says "fun times!"
>Or 1450's.....
Now you're just showing off. ;D
-
What about, at 400-450 street hp, a pair of 4180 annulars for manners?
-
I don't know that you need to get that fancy with the annuals. I have a lot of gear and converter, but I'd expect the 600s to be just as good with a 3000+ and 3.73~4.11 type gearing. On the tunnel ram, you could figure you're running 4 cylinders with a 300 CFM two barrel, which seems way less exotic than 1200 CFM of carbs, when you break it down. My 351C makes around 450ish HP in the current configuration.
When I put the tunnel ram and dual Edelbrock 1406s on the 302, the drag strip 60' only dropped maybe .05~.1, if that. It still hit the tires hard enough to pop the fronts up a couple of inches. I might have brought that back with a bit more pump shot. Maybe not, the primaries on the Eds are very efficient but don't flow so much IMHO - they are a bit like a mini-spreadbore carb. I also ran that same engine with a 600DP, 650DP and even tested a "750DP" with a ProForm body and QFT blocks - all on an Air Gap and all performed about the same. MPH always within a buck or so.
-
Not sure what your Cleveland race car has to do with my question. Anyone else care to ponder outside the box?
-
Not sure what your Cleveland race car has to do with my question. Anyone else care to ponder outside the box?
>What about, at 400-450 street hp, a pair of 4180 annulars for manners?
Carbs don't car which motor is under them. Smokey always said an engine doesn't know what name is on the valve cover. Annulars tend to go fat at higher RPM. They do help at low RPM with tall gears, tight converter, heavy car because the will atomize fuel better than the standard dog leg Holley booster. Whether it matters depends on the whole combination. Also, the T-ram on the 302 using dual 600 Eds made maybe 300 HP in good air, so HP of the combo may not be the primary deciding factor. Intake design and velocity matter. The OP asked about 450s - those are mechanical secondary carbs with only a primary accelerator pump - IMHO they would suck trying to tune for anything other than a street/strip car with lower gears/higher stall. People run them and like them, bit of a mystery to me.
-
Sorry for the 2nd post on this, but.
I was amazed 50 years ago at what Smokey was doing but that thing he dreamed up is unbelievable now and that was a long time ago.
Are you speaking of his "variable runner length" Boss 302 dual dominator intake? It didn't work. The plenum area was TOO big for two dominators. Yes the T/A engines in '69 ran them but they were designed to be used like a Weber where each venturi fed "one" port only , not a giant plenum.
-
The little carbs will usually run into fuel curve problems as power level increases. Dale touched on power potential with OE carbs, as in Stock and Super Stock apps. You can milk lots of power from OE carbs, but it becomes a science to keep the curve nice in the band that you are trying to run in.
I have done a ton of 2x4 tunnel wedge engines in the last ten years. Booster signal and management of the curve ends up being the focus to make power and run smoothly. An unhappy carb(s) will make the engine surge through a loaded pull. The dyno software usually "smooths" the surging, but screwy break specifics and lambda A/F numbers will still remain.
Drew is making some hints and speculations that would prove out if he did get to test his ideas. I think that less than 600 cfm carbs is a waste of time. If one thinks they might be "too much", use vacuum secs and play with the opening rate. Smooth but quick opening will always feel better and make more power, even on smaller engines. We do a bunch of 4160 style carbs for the big strokers. Some approach 1000 cfm each. It takes a healthy big engine, like 900+ hp to really benefit from big venturi carbs. Hard to beat a good working pair of 660s. They get fussy around 800 hp and need fuel curve tuning. As power increases, the 850s or more modified main bodies become easier to tune.
Small venturi, like 1.320, with a 1-11/16 throttle bore, are usually super good for 650 to 800 hp streetable and raceable engines. We pick a venturi size and throttle bore based on past experience, and then find main bodies that can get there. Custom tapered end mills, and radius-entry or straight taper entry custom end mills are used to get where we want to go. My man simulates booster signal and tunes the boosters to fit what we anticipate we will see. High speed, emulsion, and transition tuning all come into play.
If I were you Ross, taking a stab without much history to look at on what you describe, I would get a couple of main bodies around 1.250 to 1.313 venturi, and re taper the bottom to accept a 1-11/16 baseplate. Depending on engine size and power level, you may have to add some emulsion and go up on the high speed bleeds......maybe, maybe not. The transition bleeds are a driveability deal, and it can be done with a manual load dyno so you can simulate some driving conditions. Takes a lot of time.......
-
Drew is making some hints and speculations that would prove out if he did get to test his ideas.
Along that line.... a disclaimer for anyone that takes what I say as fact. I'm an engineer that can prove my theories with math, but ultimately I am just a dude with a car that doesn't get to drive enough to do as much R&D as I should. Sometimes I get enough feedback from customers to be able to adjust or massage my views.
Nothing can beat the experience that Barry, Brent, Blair, have in regards to hard fact dyno and race track numbers.
-
Don’t anyone get concerned, not my first rodeo, or even 10th with dual quads. I was only looking for Jay’s chart...we have a plan to test the carbs, with four more to bolt on after the 465s, and yes I agree with you Blair, expect the engine to pull real hard on the top of the curve. I will share the results.
BTW I agree with all of you, and appreciate it, but we will see if the dyno justifies the price of two new carbs. In the end, everyone has a cost/benefit line
Thanks!
-
The guys I worked with at Holley hated the old mechanical secondary, no pump 450s - called them "flamethrowers".
You can have a fair amount of fun working carbs. As Blair noted, a small, restrictive carb will tend to roll rich as airflow increases up to the point where the booster goes "sonic" and everything goes wonky. Some pretty sharp guys will work hard on optimizing vertical booster placement within the man venturi, and reducing booster cross section both in height and diameter to get where they want to go.
Annular boosters work really well at a couple things. They generate a really strong signal, tend to "start" early in the curve, and they atomize well. Historically they were used with 'oversized" carbs to soften their inherent negative low end/midrange issues. The downsides to annulars were flow reduction due to their big cross section, and a tendency to roll really rich at high speeds due to the strong signal. I've recently seen some pretty serious carb efforts with what were essentially micro-annular boosters - cross sections nearly as small as a normal downleg, and with about eighty four million very small discharge holes (actual hole count is different, but you get the idea).
The large throttle plate couple with a small venturi was an old drag racer/oval track racer trick back in the proverbial day. The standard 4150 race carb of the era was a Holley 750 with an 850 base and some blending. Might have been a Braswell deal (he did and continues to do a lot of really cool carb stuff). Holley used this platform, along with Braswell consultation as the basis for the first of the HP series carbs in the late '80's/early '90's. The marketing guys bowed to marketplace pressures and decided to refer to it as a 950HP, although actual airflow was closer to 830 cfm. It was and is a damn good carb.
The 4180 Holley was an OE carb for various Ford trucks and the 1985 Mustang GT. It had a bunch of really interesting features, and I was always surprised that it never caught on in the aftermarket. Annular front boosters and normal rears, the accelerator pump bleed hole to reduce pullover and pump well boil out, and a couple other things. Two of those might work pretty darn well on a dual quad 445...
-
Annular front boosters and normal rears. Two of those might work pretty darn well on a dual quad 445...
That is an absurd idea sir..... :P What kinda person would take a 3310-2, knock the boosters out, install annulars in the primary, stepped downlegs in the secondary and put those on his car?
With the massive Dove removable top TW it makes low throttle input/cruise pretty sporty.
(https://live.staticflickr.com/65535/49959660133_17497af507_c.jpg) (https://flic.kr/p/2j7Ljoz)IMG_4706 (https://flic.kr/p/2j7Ljoz) by Drew Pojedinec (https://www.flickr.com/photos/154777202@N07/), on Flickr
(https://live.staticflickr.com/65535/49959660278_5799ae72ab_c.jpg) (https://flic.kr/p/2j7Ljr5)IMG_4624 (https://flic.kr/p/2j7Ljr5) by Drew Pojedinec (https://www.flickr.com/photos/154777202@N07/), on Flickr
-
I like the 660 base plate on the carb closest to the camera.
-
Yeah, I just plug any vac areas on those, I like them too as they seem stouter. I like using the stock type baseplate for secondary carb so no linkage needs clearance.
-
Annular boosters work really well at a couple things. They generate a really strong signal, tend to "start" early in the curve, and they atomize well. Historically they were used with 'oversized" carbs to soften their inherent negative low end/midrange issues. The downsides to annulars were flow reduction due to their big cross section, and a tendency to roll really rich at high speeds due to the strong signal. I've recently seen some pretty serious carb efforts with what were essentially micro-annular boosters - cross sections nearly as small as a normal downleg, and with about eighty four million very small discharge holes (actual hole count is different, but you get the idea).
Why I ran a Holley 84011 for a while - what is now the Summit carb 750. Uses a front (and rear) annular venturi assembly very similar to the Ford 4100. Uses all other Holley parts - jets, vacuum diaphragms, accel pump parts, etc. I used that on a mild 351C street engine, 11" converter, 3.23 gear but with a big Weiand single plane on the engine. Great carb, still sitting up on the cabinet with a bunch of other spare carbs. Drove nice, no hesitation on street or track. I quit using it because Holley discontinued the 4010/4011 line and parts dried up - specifically the booster unit, which you had to drill to tune pump shot. Now that Summit sells the carbs, might be good again on the right motor. I wonder if they have a better time moving the carbs - Holley I think had sales trouble because "that don't look like no Holley I seen". :)
The large throttle plate couple with a small venturi was an old drag racer/oval track racer trick back in the proverbial day. The standard 4150 race carb of the era was a Holley 750 with an 850 base and some blending. Might have been a Braswell deal (he did and continues to do a lot of really cool carb stuff). Holley used this platform, along with Braswell consultation as the basis for the first of the HP series carbs in the late '80's/early '90's. The marketing guys bowed to marketplace pressures and decided to refer to it as a 950HP, although actual airflow was closer to 830 cfm. It was and is a damn good carb.
I've read somewhere a flow test on the ProForm main bodies (an independent test, not the mfg) using the billet base plate - the same 830 flow number was mentioned. Stands to reason since it's a knock off.
See whacha think of this LOL
(http://raceabilene.com/misc/84011.jpg)
-
Speaking of 4100's, has anyone worked with those, either single or dual?
I shunned them, over Holleys, "in the day" but, they seem to have some attributes with weight and those boosters.
-
4100s are great - good luck finding decent ones for any reasonable price. "back in the day" i put a cast iron 4bbl intake from the wrecking yard on my C code 289 (2bbl), tube headers and a 1.12 4100. And aluminum M/T valve covers, plus a 14" air cleaner. Car (4 door Falcon with complete interior, all steel, etc) weighed probably 3400 lbs at that time. With a RAN 3 speed and a 2.79 rear end, F60-14 tires it ran 14.6 @ 96 MPH at Green Valley.
-
I have 3, complete, good ones (all 600 cfm 1.12's) and maybe one or two others. Plus a couple of 2100, 1.14, two barrels. They also made a 1.19 (670 cfm) 4v and a 1.33, 2v but, I don't have any of those.
Like I said, I didn't use them, in the 60's and early 70's but, in the last 10 years, I've heard good things about them. They put them on a lot of Fords, in those days.
-
Speaking of 4100's, has anyone worked with those, either single or dual?
4100s are great - good luck finding decent ones for any reasonable price.
I have several, and still use the factory one on my '65 Galaxie. Easiest carbs in the world to work on, darn near bulletproof/trouble free, but like Chris said, good ones are hard to find now. The biggest problem I've found is trying to tune them. Rebuild kit choices are limited to say the least, and performance upgrades just don't exist. You're on your own. Holley jets don't work, and Ford only has 2 jet sizes that were used in them. Doesn't give many options. I'm sure guys have found lots of ways around that, but highly modifying them for big power is more work than it's worth, unless you're restricted by rules.