66 230 rochester 1bbl dual carb linkage

[papaws66]

so i'm wanting to put dual headers and dual carb intake on my 66 230. i've found pretty much everything i need to do this (haven't ordered anything yet) but i can't find a dual progressive linkage for the rochester 1bbl stock carb, as i am planning on just buying another to go with the one on it. i want a progressive linkage to keep my low end torque.
so the question i have is: Where can i find a progressive linkage for these carbs?

also.. with the exhaust, i'm planning on straight piping it out both sides and coming out at a 45 angle in front of the rear tires. is that going to be to loud in the cab to stand? i definitely want people to hear it and turn their head, but i don't want to be miserable while driving..

any help would be great! thanks

[TJ's Chevy]

If you purchase the offenhouser dual single barrel intake it should come with all the linkage necessary to make those carbs work. As far as the straight pipes...shouldn't be to bad.

[papaws66]

okay thanks. I thought it should, but couldn't find anywhere that it came with it. after looking in the reviews on speedwaymotors.com i found that it does come with a linkage, but the guy said it was junk.. hopefully he just doesn't know what he's doing and i can get it to work! and hopefully the exhaust will give the "wow" factor i want it to! some more power too! would it be beneficial to install a lump port kit? i've read that i could loose some low end torque with that, which i don't want to do..

[TJ's Chevy]

Originally Posted by papaws66

okay thanks. I thought it should, but couldn't find anywhere that it came with it. after looking in the reviews on speedwaymotors.com i found that it does come with a linkage, but the guy said it was junk.. hopefully he just doesn't know what he's doing and i can get it to work! and hopefully the exhaust will give the "wow" factor i want it to! some more power too! would it be beneficial to install a lump port kit? i've read that i could loose some low end torque with that, which i don't want to do..

The lump port kit is very helpful....as far as losing low end torque...you may loose a tiny bit, but your gain will make up for it. A "lump port head" which usually consists of- lump ports, 1.94 intake and 1.60 exhaust valves will in itself give an increase of 35+ hp...add a good cam and you add another 50+ hp. If your going to do lump ports...its well worth it to go to a slightly bigger intake valve...1.84 or the stock 1.72....that'll allow more flow which will give more power...and keeping the stock exhaust valve of 1.50 will keep your low end torque. The stock cam is a super low duration...advertised 230 degrees 196 @ .50 I believe, with .376 lift on a 114 or even a 116 lobe center...perrty much means you'll peak torque at 2500 rpm or less. So yes...lump ports will help...and more compression would to. LPG pistons are available from summit racing...something like $250 for a set of 6..and you'll get around 9:5:1 compression versus 8:5:1. Thus again...more power...if ya want...you can keep an eye pealed on my build thread. I'm hotroding a 292 I6....and in a few weeks my engine will be complete.

[papaws66]

Originally Posted by TJ's Chevy

The lump port kit is very helpful....as far as losing low end torque...you may loose a tiny bit, but your gain will make up for it. A "lump port head" which usually consists of- lump ports, 1.94 intake and 1.60 exhaust valves will in itself give an increase of 35+ hp...add a good cam and you add another 50+ hp. If your going to do lump ports...its well worth it to go to a slightly bigger intake valve...1.84 or the stock 1.72....that'll allow more flow which will give more power...and keeping the stock exhaust valve of 1.50 will keep your low end torque. The stock cam is a super low duration...advertised 230 degrees 196 @ .50 I believe, with .376 lift on a 114 or even a 116 lobe center...perrty much means you'll peak torque at 2500 rpm or less. So yes...lump ports will help...and more compression would to. LPG pistons are available from summit racing...something like $250 for a set of 6..and you'll get around 9:5:1 compression versus 8:5:1. Thus again...more power...if ya want...you can keep an eye pealed on my build thread. I'm hotroding a 292 I6....and in a few weeks my engine will be complete.

lots of great info! thanks!

[old cool]

Just curious. Did GM still use 230's in 1966? I thought the base engine was a 250 inline. That is true of my 66 GMC.

[papaws66]

Originally Posted by old cool

Just curious. Did GM still use 230's in 1966? I thought the base engine was a 250 inline. That is true of my 66 GMC.

my 230 is the stock engine. in 66 chevy had a 230 L6, 250 L6 and 292 L6 and various v8's (not sure what they are, as i don't care to have one in my truck.. lol)

[NEWFISHER]

Check out Tom Langdon at stoveboltengines.com for duals and linkage kits

[papaws66]

Originally Posted by NEWFISHER

Check out Tom Langdon at stoveboltengines.com for duals and linkage kits

are you referring to langdonsstovebolt.com ? or is that something else?

[NEWFISHER]

Originally Posted by papaws66

are you referring to langdonsstovebolt.com ? or is that something else?

He used to be stoveboltengine.com I forgot he has switched. Same guy

[papaws66]

Originally Posted by NEWFISHER

He used to be stoveboltengine.com I forgot he has switched. Same guy

okay, just making sure. i have checked his store and couldn't find a rochester linkage, only weber.. but haven't actually talked to him. thanks for the suggestion though!

[old cool]

Thanks. My engine is dated Sept of 65 with TAT on pad. Wondered if I had a 230 since gmc used chevy engines in 66. Though, literature said gmc used a 250.

[papaws66]

is it gonna hurt my truck if i drive it with open headers to go get the exhaust put on?

[TJ's Chevy]

Originally Posted by papaws66

is it gonna hurt my truck if i drive it with open headers to go get the exhaust put on?

NOT AT ALL!!!!!! Be sure to make a video!!!

[awbrown]

I think the consensus among most inliners with 2 carbs is not to use progressive linkage because of mixture distribution problems ,but it can work fine with a 3 carb setup,, I have a bored and stroked 261 with 3x1 and it has a progressive linkage my friend made for it and it works fine .. for gas milage use the monojet carbs , they are much better than the old Rochester ...

[papaws66]

Originally Posted by awbrown

I think the consensus among most inliners with 2 carbs is not to use progressive linkage because of mixture distribution problems ,but it can work fine with a 3 carb setup,, I have a bored and stroked 261 with 3x1 and it has a progressive linkage my friend made for it and it works fine .. for gas milage use the monojet carbs , they are much better than the old Rochester ...

i thought about it maybe not working with a progressive, but also thought it would get too much air if it had a solid linkage, as it is made to idle with only one rochester.. if all the cylinders are getting the same compression, shouldn't they suck approximately they same fuel no matter where the carb is placed on the manifold? i see what you're saying, being that the carb is at the back of the intake, the rear cylinders would get more fuel until the other carb opened.. but it seems to me that the only time that would happen is when you first start it and there's no fuel in the manifold, after it gets going, would it not even out? maybe i'm just underthinking though..

[papaws66]

Originally Posted by awbrown

I think the consensus among most inliners with 2 carbs is not to use progressive linkage because of mixture distribution problems ,but it can work fine with a 3 carb setup,, I have a bored and stroked 261 with 3x1 and it has a progressive linkage my friend made for it and it works fine .. for gas milage use the monojet carbs , they are much better than the old Rochester ...

on the three carb setup, does the center carb open first?

[TJ's Chevy]

Yes...the center opens 1st. But like said, On a 2 carb setup you don't need progressive linkage.

[papaws66]

Originally Posted by TJ's Chevy

NOT AT ALL!!!!!! Be sure to make a video!!!

okay, will do! hopefully Forest City doesn't have a noise ordinance..

[papaws66]

sorry for all the questions... but is the three carb setup worth the extra cost? ($299 vs 279 for manifold and an extra $179 for another carb..)

[papaws66]

http://www.summitracing.com/parts/big-11510flt/reviews
http://www.summitracing.com/parts/he...make/chevrolet
anybody see a difference in these headers, other than brand and price?

[TJ's Chevy]

Originally Posted by papaws66

okay. and even with two original sized carbs, it'll have enough vacuum?
just trying to get my facts straight before i go dump my cash into something that won't work..

Originally Posted by papaws66

sorry for all the questions... but is the three carb setup worth the extra cost? ($299 vs 279 for manifold and an extra $179 for another carb..)

Originally Posted by papaws66

http://www.summitracing.com/parts/big-11510flt/reviews
http://www.summitracing.com/parts/he...make/chevrolet
anybody see a difference in these headers, other than brand and price?

I ordered a set of Hedmen headers once and returned them for their cheap quality....The welds where poor and the metal was thin as a tin can. So basically what I'm saying is that those are crap. A good quality set of either Clifford headers or Tom Langdon's headers will be a much better choice...Clifford's short tube style headers cost $340 and Tom Langdon's cast iron non-tubular headers are something like $280 or less...I don't remember any more..You can see on his sight Langdon's Stovebolt.com for pricing. To be quite honest...a single 4 barrel carb would be MUCH better then the dual single barrels...not only will it be much easier to tune, but you'll get better mileage and you will be able to cruise easier. Remember that any dual single barrel or 2 barrel will not out perform a single 4 barrel. But to have the older style looks of dual carbs gives it more of a "cool" factor as well imop. So lets look at it cost wise...

Cifford manifold : $299
Offenhauser manifold $279
Clifford headers(short tube) $340
(Long tube) $420(?)
Hedman headers $204
Tom Langdon's headers $277
Two new Model b rochesters. $327.94 from summit
Edelbrock 500 cfm 1404 4 barrel $309.97

So....With a Clifford intake, Tom Langdon's headers and an edelbrock 500 yer looking at $885 and whatever shipping. Now if you were to do the same thing with two new rochesters, an offenhauser intake and Langdon's headers yer looking at $883...no difference, but the issue with the offenhauser is that the water lines are hard to hook up...the clifford intake utilizes heater hose for the water heated intake. So if you want good lasting quality...go with the clifford intake and either a set of Tom Langdon's headers or clifford's headers...the premium carb would be a 390 holley, but a mildly jetted down 500 edelbrock should work as well....and you'll want to convert to an hei as well.