Anyone running dual carbs..

what is your setup? are u running webers/mikuni's 40's,44's, 45's... how do u fine tune them... some coupe guys tell me that they can just tune them by sound w/o using the synchronizer.. also what is the range of jet sizes the mains and air have to be so that I don't eat alot of gas...

I,m running 40mm Mikuni's on a built 20R, fine tuning is basically getting the throttles adjusted correctly, getting the air mixtures adjusted to the best vacuum or idle quality, from there on its a trial and error to get the jetting dialed in by reading the plugs, like any carb setup.
Throw the synchronizer out the window, worthless unless you can do the adjusting in a flash, using it is like pulling the choke out or putting your hand over the carb throat and trying to adjust the carb, don't work worth beans.
Out of the box jetting is the best starting point then go from there, as each engine will have their own sweet spot.
I,m running 57.5 pilots, 140 mains drilled to .063 and a 180 main air, no stacks and K&N filters, also a vacuum accumulator with vacuum storage tank and a Mallory full centrifical ignition setup. Have fun.

wow u did the 20R hybrid.. thats the shit... before puttin my duals on I probally going do some head work and a cam install then probally hook it up.. just the tuning am concern because don't want it to run into problems.

I ran dual 44 Mikunis on my Corolla tubed them fine, the syn tool is gopod to have and use it will pin point any vaccum leaks if any on each cylinder, Right now I putting a TRD stage 1 cam dual 40 Webers and a header on my truck with my head cut .40 to boost compression a little

u did the 20R hybrid..

The engine with the dual Mikuni's is a 20R, but I have built a couple of the 22r hybrids, in fact I,m building another one now to replace the one above hopefully sometime this summer, that way I can retain the dual carbs but up the cubes a few.

Right now I putting a TRD stage 1 cam dual 40 Webers and a header on my truck with my head cut .40 to boost compression a little[/quote]

Damn!! boost the compression a little with a .40 cut I think it'll still ping on avgas with octane booster with nearly a half inch of head milled off

I got dual 40mm sidedrafts and have had good results with the sychronizer,I got a Jasper bored .030 over with the 20r conversion LC header and Crane ignition LC centrifical distributor...and a few other little goodies in the mix

I,m outnumbered on the sync tools usefulness, We talking about the same type, the plastic dial gauge with the rubber plug you shove in the carb throat?
I just never seen where it did much except choke the carb down and give a somewhat visual of air flow, but as a real tuning aid it didn't buy anything for me. A vacuum gauge and my ear worked for me.
Oldskl and 3TC, a couple of nice upgrades to your engines, have fun, stock sucks.

yeah i got ya .040

Damn!! boost the compression a little with a .40 cut I think it'll still ping on avgas with octane booster with nearly a half inch of head milled off [/quote]
yeah i got ya .040 [/quote]

I figured that was the case but thought I could give ya a bad time anyways
Even then, .040 is quite a cut, retards the cam timing back, plus the head cut, and a higher lift cam, hopefully the valves and pistons don't get too personal