Carb suggestions for TR

[GofastRacer]

There is absolutely nothing wrong with VS carbs on a tunnelram, all it takes is tuning and the worst thing is to turn them into mechanical secondaries since there are no accelarator pumps for the secondaries. The trick is to get the secondaries to start opening at a smoothe rate as quick as possible without a bog right after the primaries are open, also a vacuum line connecting both diaghprams is mandatory to keep both working simultaniously!. Another thing a lot of people do is eliminate the little check ball, that is a no-no because all that does is allow the secondaries to slam open and that will cuase it to fall on it's face!..... Now to eliminate all that BS, throw the carbs in the trash and put a hat on the tumnnelram and forget about it. OH, and it will go on any size motor it don't care!..

[Blown 472]

There is absolutely nothing wrong with VS carbs on a tunnelram, all it takes is tuning and the worst thing is to turn them into mechanical secondaries since there are no accelarator pumps for the secondaries. The trick is to get the secondaries to start opening at a smoothe rate as quick as possible without a bog right after the primaries are open, also a vacuum line connecting both diaghprams is mandatory to keep both working simultaniously!. Another thing a lot of people do is eliminate the little check ball, that is a no-no because all that does is allow the secondaries to slam open and that will cuase it to fall on it's face!..... Now to eliminate all that BS, throw the carbs in the trash and put a hat on the tumnnelram and forget about it. OH, and it will go on any size motor it don't care!..
Doesn't the vacuum loose it's signal at wot? He should get a vacuum gauge and hook it up and that will help tune where you want everything to work? power valves and give you and idea if you have vac at wot.
I have two 800 holleys with linkage and everything I will sell ya, off my blown motta as I am going injected, hehehehehehe :crossx:

[GofastRacer]

Doesn't the vacuum loose it's signal at wot? He should get a vacuum gauge and hook it up and that will help tune where you want everything to work? power valves and give you and idea if you have vac at wot.
I have two 800 holleys with linkage and everything I will sell ya, off my blown motta as I am going injected, hehehehehehe :crossx:
No because it's venturi vacuum that opens them!..
That's ok, you can keep the carbejemators!.. :crossx:

[OverKill]

I had a single Holley 750cfm on a wieand TR. I would get to about 4500 rpm back off to 2000 rpm then go back up to 4500 and I would get a sputtering sound. I checked the plugs and all were jet black wet. I did a vacume test from the carb. and I was all the way up to 13psi at 4500 and sometimes got it to 15psi at 3900 way to high. That carb. had vacume secondaries. I put an 850cfm Holley with MS and no problems, even added a 1.5 Wilson spacer and got even better response. So I feel there is a signal problem with VS and TR's. Just my opinion.
OverKill

[texas-19]

I'm toying with the idea of vacume secondaries, or possibly the Holley 450
4160 mechanical secondary. I see where Summit and Jegs are selling that 450 for $193 so the price is right.
Dan
You'll have $400.00 + in 2 450's and then have to be tunning on them.Just break down and get the 850 dp.You will be a whole lot happier with it.Troubleshooting will be alot easier and less headache.I'd look for a good used one,you can still run what you have and be looking for a good used one for probobly less than those 450's will cost.
I had the same situation.Had a tunnel ram on with 2 750's,swapped to an 850 and never lost any speed and got better gas mileage.

[Kindsvater Flat]

I have 600 vac sec on my tunnel ram and they work great. No hesitation or anything. Never flood it either.

[OverKill]

I second that

[DUCKY]

I guess I was confused, I thought you were looking at the 450cfm V/S carbs that Summit sells with their tunnel ram combos. Not mechanical secondaries. I seriosly doubt that the mechanical 450's will be much better than your 660's on the economy side, and they will certainly cost you some top end. If it were me, I'd get the 450's (v/s) and run them, and save the 660's for your big motor.

[AzMandella]

If you want to run vac-secondaries go for it.I run a set of 750's on my 514 and when it comes to racing you wouldn't know thwy were vac's.And they get much better fuel milage when cruising or skiing.It all depends on what springs you use.Quick Fuel Technologies has a new secondary diaphram housing that will let you change the opening rate by turning a screw.You also have to run a balance tube to keep them opening equally.
http://i5.photobucket.com/albums/y18.../carb002-2.jpg
http://i5.photobucket.com/albums/y18.../carb003-1.jpg

[67weimann]

AzMandella, at least you could have thrown a quick spit shine on those velocity stacks before you snapped that pic...j/k