Has anybody ever used the holley 660 center squirter carbs on the street with any luck?Are they streetable?What about the 450's without the vacuum secondaries?Are they worth looking into?I'm putting them on a .040 over 454,9.5 static comp,square port cc heads with a 294s comp cam.

Thanks

No one here messes with dual carbs?

nope....only Gene,but he has 3 of them :D

gonna be rich with 660's and low on torque,too much cam and head ,not enuf comp ratio for the combo

Well 9.5 comp ratio is a conservative guess. I think it will be higher but I hope it isnt. If the 660's are too rich then the 450's should be better then. Is that correct?

i've been messing with dual carbs for awhile.i guess..off and on when the mood strikes....ive had a few sbc dual carb set ups on the street and i have a bbc now that has dual carbs........i have never used the 660 center squiters.just regular run of the mill 600 vs carbs.........i havent mess with the double pumpers for the street just because i knew they would be to much for about anything....but i have done quite well with the vs 600 holleys..even ran a pair on a stock 305 short block and 305 comp cam for just shizzts and giggles the engine had right at 8.5 to 1 compression or so......i was able to run that mill on the street with a 4500 convertor and 4.56 gears out back......it was fun .......street matters suck'd but it sure did run ok for what it was ..ran mid 13's....it didnt cough or sneezed.it just ran......wild idle with that 305 comp cam........anyway.....i have kinda thought since that little fun engine did well with dual carbs i didnt see any reason why other engines would be a problem........ok im just rambling now......thought i would share.....

Thanks guys, I know Gene has three :D but that doesnt really help me. I guess my combo is different but I want to run dual fours just for the looks but I dont want it to be totally unstreetable. Im hoping my compression will be around 9.5 to 1 but I think it figures to be closer to 10 or 10.5 to 1. Oh well guess Ill just have to try them and see, when I get that far.

Have you considered a pair of 500 cfm, AFB type carb's?

I ask b/c they package real well on two-four barrel carb. manifolds. They should be sized good for your motor AND finally, they have historically been used for this application.

pdq67

I was kinda wanting to stick with holleys. Holley makes a 450 too.

my experience was with a small block 400 with afr 195 heads and a comp 294 solid cam. we used a weiand street tunnel ram and stock 450 holleys. in a 68 firebird with 10" converter and 3.73 gears it ran awesome. the engine had about 10.5-1 compression. good luck mike

Be sure to post if they work or not. I have been sitting on a pair of 660s and a T-ram for awhile. Got side tracked from the T-ram by going with a blower and it came with other carbs. Mine came off of a jeep that was raced in sand drags with a blower and it was a mean SOB. Someday the setup will find its way to the street.

Well it will be awhile because Im still putting it together. But maybe I can get a friend to put on his 454 to see how it does.

just ordered a blower but i was going to try these. guess the'll go on a shelf now. :(
http://img.photobucket.com/albums/v478/panchop/MVC-451F.jpg

the 660s have almost 1:1 throttles,they are not suitable for street use........I use them on my 355 on a Holley Pro Dominator and they are excellent carbs but for street use there may be some drivability issues,not to mention they wont be very economical. Look at something with a progressive throttle plate similar to the double pumpers and you probably will be happier :cool:

While the 660's aren't perfect street carbs, they can be made to work pretty decent. I used a set on a rectangular port 396 with tunnel ram years ago and they actually did very well.

Since linkage is 1 to 1, you will need to contour the slot on the secondary cam linkage to delay secondary opening as much as possible. I actually purposely contoured mine different on each carb to allow a slightly progressive opeing of all 8 barrels.

Stock they open all 4 barrels on each carb simultaneously. The accelerator pump shooter is in the middle and dumps into all 4 bbls at once. That's why they are called "Center Squirters". They will be rich on the idle circuit, but a little restricting will have them working OK.

I would definitely kick up the compression. I used an old Weiand Tunnel ram that had a divided plenum that I am sure helped streetability. Also look into using LOTS of timing to keep throttle response sharp. I was using an old dual point with a toggle switch on one set of points. I ran around on the street under light load with 55* of timing. When I nailed it hard, I would flip switch at top of 2nd or into 3rd gear and it would fall back to 38*. Worked great..of course now days you can get cool timing computers to do all this stuff.

No way I would use the little 450 cfm carbs. I wouldn't hesitate for a second to install two 750 DP's with power valves on a 454. It would be easier to tune that 660's, but again 660's can work.


JIM

Originally posted by greg etts:
just ordered a blower but i was going to try these. guess the'll go on a shelf now. :(
Greg, I have the same setup as yours, but with two 450's. The linkage on the 450's is not 1:1, so I think it should be pretty streetable. I'm going to be trying them this spring on a 427.

I have a pair of 450 mech Holleys on an early Offy 2x4 intake,on my 427.I have tuned them and not had to touch them for 12yrs[8k miles];except for last week when the rear plastic float decided to become porous on me! I have found them to be very reliable and no prob. in hot/cold starts.I cruize through town and they idle well and they run fine.Most people look and think they'd be a hassle to keep in tune but there not!Its been so long I cant even remember the settings! but my eng is a 10.5comp,crane 290 with mild SPOC heads.Even so, I'm thinking of going 1x4bble again,as I'd like to try an Airgap and a 780/850. ..later...Dave

Personally I don't like the 660s even on race cars. The 6109 750 is a far superior carb for tunnel ram applications. For a street setup (I do not recommend a tunnel ram on a street car) the 450 vacuum carbs can be made to work reasonably well as long as you don't drive it in cold weather.

Mike, the 450's are mechnical secondaries, without a secondary accelerator pump. No choke provision, and metering plates on the sec.

I have the Offy low rise 2X4 intake and I have 2 650 dp but I will have to make some custom plates to get them to bolt up. The 660 or the 450 will bolt up without any mods. It will be awhile before I get to use these but I was digging through my parts and saw them. So I had to ask. :D I appreciate all your replies because the more info I have the better Ill be ( I hope).

A friend of mine ran a pair of 660's on a tunnel ram and on a low rise Offy dual quad intake on a few Olds 455's and 425's he had.
I driven both set-ups,and they had some pretty incredible throttle response IMHO
I did always wonder how the 450 cfm carbs would have done.

I was lurking around the cobra boards where 2x4's is fairly common, and that was the one thing all of them said. Throttle response is incredible. My concern is reversion at high rpm, as the casting is pretty primitive.
When the snow goes, I'll let you know!