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Discussion Starter #1 (Edited)
So i'm contemplating buying a Wieand tunnel ram with dual 600 VS holleys.

Its a 496, bigger valve, mild worked oval head, .630" lift roller cam, that currently has an 850 DP on it.

I've just spent a few hours reading about tunnel rams and carb tuning using the search tool.

I guess I've just always wanted one, but is it worth it? Its just a lake boat that i don't need every inch of power out of, but it seems like they really are a great intake. It seems properly tuned they don't produce any noticeable increases in fuel consumption, but wake the throttle response all over the RPM range.

Next question is, is the 600 VS not enough on a 496, I'm not going to use the 660's but most guys are saying the 750s are better than the 600's. Could the 600's just be jetted bigger? Or is the VS just gonna cancel out the benefit of wicked throttle response while waiting for the vacuum signal?

Sorry its so wordy, I just keep going back and forth...and back and forth again.
 

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I've got two 600 DP's on a 565 that pulls very hard to 7500. If you think about it, 2 600 VS's just running on the primairys is still 600 cfm which is almost 2/3's the flow of the 850 wide open. There are also kits available to convert to mech. sec., from Quick Fuel among others. If you stay with the vacumn, Quick Fuel also makes quick change kits that allow for tuning.
 

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So i'm contemplating buying an Offy tunnel ram with dual 600 VS holleys.

Its a 496, bigger valve, mild worked oval head, .630" lift roller cam, that currently has an 850 DP on it.

I've just spent a few hours reading about tunnel rams and carb tuning using the search tool.

I guess I've just always wanted one, but is it worth it? Its just a lake boat that i don't need every inch of power out of, but it seems like they really are a great intake. It seems properly tuned they don't produce any noticeable increases in fuel consumption, but wake the throttle response all over the RPM range.

Next question is, is the 600 VS not enough on a 496, I'm not going to use the 660's but most guys are saying the 750s are better than the 600's. Could the 600's just be jetted bigger? Or is the VS just gonna cancel out the benefit of wicked throttle response while waiting for the vacuum signal?

Sorry its so wordy, I just keep going back and forth...and back and forth again.
well...since you have all winter to think about what to do...i would give some consideration to a better set of heads (rect port)...a good sgl plane manif (Brodix, Dart, Team G)...perhaps an upgrade on the ign ststem...re-work the 850 carb to flow better or maybe a 1050 Dominator...these are just my suggestions & perhaps $$$ spent in a better way :)...T/R's are nice & pretty, but, except for showing off, MHO is, you can make a 1x4 set-up work just as good with less headaches :)...its just a lake boat, not a racer!...just sayin' my .02 cents :)

FastRat
 

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AKA Blownjet 468
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changing an intake ain't no big deal. try it, you don't like it, change it back! 2-1850
holley's are a very forgiving setup! won't take much to get them tuned right, and you
will find that throttle response won't have suffered, and will pick up midrange and top
end! and will look cool too! :p it's an oval port ram, right?:)sphss
 

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Discussion Starter #5
well...since you have all winter to think about what to do...i would give some consideration to a better set of heads (rect port)...a good sgl plane manif (Brodix, Dart, Team G)...perhaps an upgrade on the ign ststem...re-work the 850 carb to flow better or maybe a 1050 Dominator...these are just my suggestions & perhaps $$$ spent in a better way :)...T/R's are nice & pretty, but, except for showing off, MHO is, you can make a 1x4 set-up work just as good with less headaches :)...its just a lake boat, not a racer!...just sayin' my .02 cents :)

FastRat
HaHa, FastRat you're not helping! lol. All that resonates with me, and I do take it into consideration.

It is an oval port T/R.

Thanks for all the input, I'm all ears!
 

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steelcomp was here
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changing an intake ain't no big deal. try it, you don't like it, change it back! 2-1850
holley's are a very forgiving setup! won't take much to get them tuned right, and you
will find that throttle response won't have suffered, and will pick up midrange and top
end! and will look cool too! :p it's an oval port ram, right?:)sphss
X2. Give it a try...you'll be surprised, and not disappointed.
 

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Yea just give it a try, T/R with carbs are pretty plentiful out there right now. They are much more than just "showing off" as some may have you believe. And for a lake boat that has a driver that is not afraid to keep the pedal mashed down for more than 100ft at a time then you will see what i mean when all that carburation comes alive. You have to want to use them to their full potential.
 

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On a 496 i would be looking at a set of aftermarket heads before a TR setup. Sure you'll probably gain a few Hp with the TR but a good set of heads even with a single carb will net you far more Hp gains. By the time you buy a TR, carbs, linkage and a new scoop or tray you could probably find a good set of used heads, check 'em over and throw on a set of new springs and gain 100-150hp.:)
 

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Discussion Starter #9
Keep 'em coming, I like hearing where people are coming from.

But what about jetting and power valves and metering of the 600's? And what about the VS? Should I convert to mechanical secondaries, or will the VS be okay? If I find its running lean would jetting help, or would bigger carbs be in order?
 

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On a 496 i would be looking at a set of aftermarket heads before a TR setup. Sure you'll probably gain a few Hp with the TR but a good set of heads even with a single carb will net you far more Hp gains. By the time you buy a TR, carbs, linkage and a new scoop or tray you could probably find a good set of used heads, check 'em over and throw on a set of new springs and gain 100-150hp.:)
AMEN brother!...i rest my case:)

FastRat
 

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PA, I would look to a different brand of T/Ram than an Offy! Weiand, Edelbrock seem to make better performance than the Offy! The heads you have maybe holding you back also! For Carbs I like to go with the classic DP in a 650 to 850 CFM to get the most bang for your buck with a T/R! JMO! WT:)devil
 

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steelcomp was here
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Keep 'em coming, I like hearing where people are coming from.

But what about jetting and power valves and metering of the 600's? And what about the VS? Should I convert to mechanical secondaries, or will the VS be okay? If I find its running lean would jetting help, or would bigger carbs be in order?
Bigger carbs won't make it run richer. The first thing I'd do to the 1850's is increase the PV metering passages by about .010". You have secondary jet plates, not metering blocks so secondary jetting is tricky. I'd have the secodaries coming in at about 2500rpm which can be adjusted with the diaphragm spirngs. Squirters and pri. jets and PV's should remain stock to start, and go from there. Make sure your timing is set or you can chase your tail with carb tuning.
 

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just a ski boat with bark
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changing an intake ain't no big deal. try it, you don't like it, change it back! 2-1850
holley's are a very forgiving setup! won't take much to get them tuned right, and you
will find that throttle response won't have suffered, and will pick up midrange and top
end! and will look cool too! :p it's an oval port ram, right?:)sphss
X2. Give it a try...you'll be surprised, and not disappointed.
I'm going to say X3, if you got it try it. If you don't have it then maybe more info on your combination is needed but it you have it already for the price of some gaskets and a little work it'll be worth it.

FWIW, the tunnel ram picked up ET and MPh for me.
 

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I'm going to say X3, if you got it try it. If you don't have it then maybe more info on your combination is needed but it you have it already for the price of some gaskets and a little work it'll be worth it.

FWIW, the tunnel ram picked up ET and MPh for me.

X4, if you already have it, why not try it and see what you think. But if your going to be buying it all i'd definitly look into heads, way more power to be gained there.:)
 

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X4, if you already have it, why not try it and see what you think. But if your going to be buying it all i'd definitly look into heads, way more power to be gained there.:)
even If your gonna buy it all,
#1-I would buy it used-lots out there-just look in the spam here!
#2-genuine holley quick kits are bout 30bucks each- +the right PV's another 20.00
#3 I've set up quite a few rams w/ 1850's- rarely above a #68 pri jets-number drills for
secondary tuning- and most of the time a yellow spring-and 3.5/4.5 pv, determined by
camshaft.....
#4-yes heads would deffinatley up the power, but not at even close to price of a used
ram and rebuilt carbs......just my 2 cents:D
 

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steelcomp was here
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even If your gonna buy it all,
#1-I would buy it used-lots out there-just look in the spam here!
#2-genuine holley quick kits are bout 30bucks each- +the right PV's another 20.00
#3 I've set up quite a few rams w/ 1850's- rarely above a #68 pri jets-number drills for
secondary tuning- and most of the time a yellow spring-and 3.5/4.5 pv, determined by
camshaft.....
#4-yes heads would deffinatley up the power, but not at even close to price of a used
ram and rebuilt carbs......just my 2 cents:D
X2.
 

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Well GN you beat me to it. I will say it anyway. Put some 990 heads on it and a BIG Isky cam and a Tunnel with two 750's and you have a 100 mph boat. Just ask Quickjet. :D
 

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What kind of boat, is it a v-drive or jet ?

What type of boating do you do the most ?
 
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