Offy tripple 1 v/s popular 2bl

I'm just curious why it seems as though no one is using the Offy triple setup. Is it cheeper to modify for a two barrel carb setup? More power? More reliable? Just curious because there seem to be so little info out there about the triple setup.

Thanks

Triples are cool
Triples are fast
I believe that triples have a better chance of preserving MPG as long as you keep your foot out of it.

But, triples are complex, both in physically installing them and working out the linkage as well as tuning them. And there is the additional costs of not only the adapter but purchasing 3 carbs vs a single.

I rode in a '66 Mustang with a 200/3.03 with triples (Colorado66), it was such a different animal compared to my friends '66 200/2.77 1bbl (sharris).

I think a 2bbl is just easier, a single hole to modify, no carb balancing required, single throttle actuation, easier fuel routing, easier troubleshooting.

More cfm with the trip's. even with the old 170 carbs 3x 156 cfm=468 spaced out along the log and progressive for low to max demand.
Remember the old Pontiac and ford tri powers that's the way it was done
My way

Plenty of info, it just hasn't been stickied. If you surf the net, you see 1965 Jikov tri power inlinesix all over the place as a video poster.

Here, there is an epic six page post by echo1955 viewtopic.php?t=63640

And other posts as well from frequent fliers

http://www.fordsix.com/forum/viewtopic. ... 47#p541547


2-bbls are better for fuel surge control and consistency in a drag racing environment. The fact is, there is probably about 25 more hp to be had with a well matched 500 cfm Holley 2-bbl on a 200 verses the best tripower 34 Weber on a 200. The big throat 1904 and 1101/1940 big throat carb combo can make 220 on a 250, but either way, you will get great results with Tripowers if you use the right carbs.

Your peak 1.5"Hg carb cfm as you would measure a 4-bbl, with the smallest 1100's, you'd be lucky to get 255 cfm. With good kinds of 1100's and 1101's is just over 445 cfm.

Rated as a 2-bbl, that's 360 to 630 cfm, as good as or better than the 7448 350cfm, 4412 500cfm or 6425 650cfm 2-bbl Holley

Despite being down over 200 thou for venturi size, a set of three 34 Weber ICT's with 1.147" 29 mm venturis flows best at 466 cfm total, which is equal to the best triple large venturi 1.352" 1940 Holley, at 449 cfm. That's 659 or 636 cfm.

To get the best combination of cfm and peak power, you have to hunt around to find the right carbs and the right small chamber 170 head, preferably with the bigger log.


The limitation is that the three holes to the log head limit the total cfm to well below those 360 to 658 cfm 2-bbl ratings. The intake manifold casting is the pinch point, with the early head before 1967 especially bad, the later C9 heads with the bigger than 1.5" hole a lot better.


Our overseas guys from Holland like jdn21758 and other poster children of TriPower goodness exist, its not fair to single any out.

But here's just a faction of them. There are hundreds.
JOHN G http://www.fordsix.com/forum/viewtopic.php?t=20605
64falconsix http://www.fordsix.com/forum/viewtopic.php?t=58378
64 200 ranchero Outer Weber ICT's, inner 1101, but he's had lots of other Holley 1-bbl combos http://s1028.photobucket.com/user/64200 ... t=3&page=1
powerband has just about every type of 170/200/250 tri power and 2-bbl carb log combo I6 made
memberlist.php?mode=viewprofile&u=97
datac viewtopic.php?t=70151
kevinl1058 viewtopic.php?t=64712
FalconSedanDelivery viewtopic.php?f=40&t=41798&p=502631#p502631

FalconSedanDelivery":mvy2nx2n said:

Finally got to test My 250 Engine ,in My 65 Mustang , Best Et was 14.55 @ 90.97, Terrible 60ft times ( Need More Converter ) will be installing a Higher stall unit to be ready for the 3 day race at my home track, 13's should be the result " Beaver Springs Dragway ", --http://beaversprings.com/ 250 .040, 1100 center, Little Holleys on ends , Crane Solid Cam .460int, .480exh Duraspark ign with GM 4 pin Module , 12-1 compression ( head was milled .120 , Deck .100 , Clifford Headers twin outlet ( open exh Drag car only ) car is a 1965 Mustang 3.50 gears C-4 with 10 inch converter ,( out of my 68 Blown 390 car ) 26.5 Slicks , Moroso Electric Water pump drive , adjustable Rockers , port divider in head , shift at 5000 , 4300 thru the traps

Click to expand...

FSD set up is very creditable 200-225 flywheel hp, and most likely the most powerful triple 1-bbl around. He ran a unison linkage, high initial advance of 16 to 18 degrees, total timing to 30 degrees its all in at 2350, decked block 100 thou and head 120 thou for huge 12.3:1 C/R, and the worlds neatest tri power intake ever seen. His best was 14.39 @ 91.76 mph one hot June 2011, and was shifted at 5000 and 4300 at the traps, earlier runs were 5200 and 4700 rpm. He ran with 3.5:1 gears for the 14.39. Best 60 foot time 1.915 secs in a 2600+ pound car with a an estimated 165 at the rear wheels. That's a minimum of 220 hp with a C4, probably more

CobraSix, Slade has had Aussie 2V and tripower and many informative posts like this viewtopic.php?f=11&t=665&p=4483#p4483


The Tri Power has some serious short comings with some of the carb sizes and holes being woefully inadequate for performance, but anytime you have three jugs supplying fuel to six cylinders, the total system loss is less than the best 2-bbl direct mount.The two best recored hp tri-powers are kevinl1058's 200 and FalconSedanDelivery's 250, with flywheel hp, by my calculation, or 181 and 220 flywheel hp respectively.

The best thing about the tripower is fuel distribution. It makes up for its very bad porting sizes by having a very straight shot to the cylinders.

We have TOTALLY missed the lesson of the 1960's and early 70's Aussie and British triple carb I6 engines. In the 190 hp 15.3 second quarter mile 202 XU1 GTR, some of the the Healy 3000's, there were three 1.75" holes feeding each group of two cylinders, yet our, WITH RESPECT, stupid Offy and Edelbrock tripowers, we try to get away with 1.09" or 1.4375" on the outers, with 1.3, 1.65, or 1.75" on the centers. It was expedient as a solution, but dumb in 1960, and 1975, and is dumb now, yet we are still getting 181 hp from a 200 and 220 hp from a 250. And that shows how smart the US cam and exhaust tuners are.

They do add a better performance level to the engine, but I think the approach of how you have to attach it to the log turns a lot of people off to them for this engine. If you could simply unbolt and swap the intake like most other engines, I think you would see a lot more of them.

A definite breathing advantage can be built with three vs one intake port on the intake runner, the typical 2Bbl conversion has the deficit of grossly unequal runner lengths to the valves (ports).

Three reasonable CFM carbs dumping in @ 2 cyl' each - either synchronous or progressive depending on needs adds some controlled breathing to a serious performance build. Triples are cool - Triples are fast and can be completely road drivable when setup progressive. A nice big 2Bbl may be a simple tune on a V8 but a big 2Bbl wants lots of flow/ vacuum to not lag off idle or at cruise on a small block six.

If you could simply unbolt and swap the intake like most other engines,

For fun I built a Hi-Rise Plenum 2Bbl intake using the multi-ported Offy 3X1 adapter three port conversion for a semi bolt-on intake . With the 274' cam profile it's more stable at idle than 3 Holleys could stay ', the best of both 3X1 and big 2Bbl,,, The 3 port common Hi-Rise Plenum allows for a more a constant A/F at the runners than the direct mount 2Bbl setup.

. .


/ . /





have fun

Yeah!

Rectangular holed Steel Section Intakes rule my world!

And Trough Plate/Hot Plate or Away In a Manger I-sixes like the old 50s Nash Rambler 196 cube I6 that became the AMC Jeep engine, and that Ford modled the little 144 and 170 log Sixes off.



But there's still room for three YFA's on that tunnel ram powerband.

http://www.youtube.com/watch?v=lOKbQLEv1pA

429 cfm of 4-bbl rated carburation, or 606 cfm of 2-bbl rated carburation was never, ever easier than three 1.4375" venturi, 1.6875" stock emissions era Carters.





Or Frenchtownflyer style twins

xctasy":2xeav2f1 said:

......We have TOTALLY missed the lesson of the 1960's and early 70's Aussie and British triple carb I6 engines. In the 190 hp 15.3 second quarter mile 202 XU1 GTR, some of the the Healy 3000's, there were three 1.75" holes feeding each group of two cylinders, yet our, WITH RESPECT, stupid Offy and Edelbrock tripowers, we try to get away with 1.09" or 1.4375" on the outers, with 1.3, 1.65, or 1.75" on the centers. It was expedient as a solution, but dumb in 1960, and 1975, and is dumb now, yet we are still getting 181 hp from a 200 and 220 hp from a 250. And that shows how smart the US cam and exhaust tuners are.

Click to expand...

Keep in mind, though, that SU's are constant velocity carbs and more forgiving of over-carburetion than those simple Holleys. Also, in the Healey, Aston, and Jag, the carbs typically didn't feed a log. Each SU was servising two or three cylinders per carb with a small balance tube between the carbs. The calculus for cfm changes as you split up the manifold into segments like that (ultimately you might arrive at 1100 cfm for an IR equipped 200 ci engine!).

Still, you make a great point; the log head is severely restricted and needs all the help you can give it. I would love to see a triple HS6 arrangement such as that rare Lynx setup on a dyno.

http://www.mustang.org.au/forum/index.php?topic=22144.0

Those bigger 1904/1940/1100/1101/YFA single carbs are 1.29 to 1.352 to 1.4375" venturi with 1.6875" throttles, able to be tuned to run as three. A brace of HS6 or HD8 are 1.75 to 2.0" throttle, with a variable venturi, obviously bigger, but on engines that aren't bigger than our 200 and 250 engines.

There real issue is making the holes under each carb the same size as the three 1-bbl carbs. Then it would honk.

Look at Ak Millers engines from the sixties with four Kehin's or two HD6's or old Tillotson Harley carbs, the heads didn't have pocket blending or whatever, they were stock heads with a little shaving, a better spring set, and headers and better carbs. Power went up from 65 rwhp to 115-125 rwhp, or 145 to 158 flywheel hp with no port work.

As it is, even with the restrictions, a good Offy or Edelbrock tri power, even with Weber 34 ICH/ICT's can go well over 180 hp with just the smaller holes and some porting. Or 220 hp with the bigger US 1-bbls, and the best compression ratio and piston decking. That is a miracle.

A properly worked Tripower with bigger holes under the carbs is just itching to bust out, hiding a lot more power than a brace of difficult to tune and hard to get Skinner Unions, or modern replacement Mikunis.


Those old Holley, Autolite, Motorcraft or Carter carbs or modern replacements that CI sells are everywhere, and adjustable.

First big break was the awesome triple 1.75" hole adapter, the best one from one from our member here rwbrooks50.

The offy is too tall and too small in porting to work well, so your better off making a low deck welded intake like on rwbrooks50's website

http://s529.photobucket.com/albums/dd33 ... 0Ranchero/





None of that namby, pamby, la-de-da small a$$ 1.09 or 1.4375" inch outer carb hole crap the Offenhauser and Edelbrock bolt on log adapters force us to stomach...

The Argentinians have been doing it for years...

Hey Blackbird66'

So ya' thinkin' of gettin' in the Tr-Power cricle ?... . as you can see a small but enthusiastic group can provide encouragement and maybe a few helpful hints.



have fun

Tri-Power Small Six describes and illustrates an era of Hot Rod development with innovative and useful performance modifications realistically home-buildable in their simplicity of form following function.
.

would (3) weber 32/36 carbs be too much for a tripower set up?

kevinl1058":29azgp8w said:

would (3) weber 32/36 carbs be too much for a tripower set up?

Click to expand...

The 32/36 progressive 2Bbl's are one of most widely tunable carbs available . I'm sure they could work, three individually progressive - synchronous linkaged' 2Bbls with suitable jetting would fit right into most Small Six build parameter CFM needs. The logistics of fitting three 32/36's would be the challenge.

have fun

Are there any progressive 2 barrels carbs smaller than the 32/36?

Does Dellorto make anything?

Hey Blackbird66'

So ya' thinkin' of gettin' in the Tr-Power cricle ?... . as you can see a small but enthusiastic group can provide encouragement and maybe a few helpful hints.

Yes, I'm thinking about it. I didn't know it was an option until recently, and although the 2 barrel conversion is very popular, I hadn't seen any info on the tri- carb.
What I do I have to do to the log head, other than drill holes? Does the offy just clamp down on the log with a thick sealing gasket, or do you have to have the head milled flat for a good gasket surface?

Powerband-how do you close the hood?
My way
Ooop's didn't see the hood bubble in the windshield pic right away. Nice work. Could widen at carb to mount 4 barrel as the large log would take care of evening out distribution.
My way

You can always simply make it a free-air induction - drove' the Comet this way for a few years before taking body-work...

so what gave more power, 3 singles or a large 2bbl w/plenum? very cool idea

my way":3p8138iw said:

Could widen at carb to mount 4 barrel as the large log would take care of evening out distribution.
My way

Click to expand...

you would have to widen the entire log, or add a second parallel runner to add a four barrel carb to the small six. and if you choose to do that, i recommend using the 390 cfm holley or the edelbrock 500cfm four barrel carb. these are small carbs, with either a vacuum or air valve secondary, and would tolerate operating on the smaller engine.

so what gave more power, 3 singles or a large 2bbl w/plenum? very cool idea

Click to expand...

three ones will give better power due to more equal airflow between cylinders.

Is anyone running them synched or mainly in a progressive set up. It would be a whole new jetting mapping but if I can get the response of wide open right off the pedal it may be worth playing around with?