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Wesser
03-09-2008, 12:55 PM
Gonna order a new holly 4160 carb this week.Should I stay with the vacuum secondary or go with a mechanical?Also should i stay with the 600cfm or go to 750?

TMCNo1
03-09-2008, 02:16 PM
OEM is vacuum secondary. Vacuum comes in much slower than mechanical to prevent a sudden speed increase when it comes in.

EricB
03-09-2008, 02:25 PM
If you want to double your fuel consumption, go with the mechanical secondaries.

jimmer2880
03-09-2008, 03:54 PM
I've heard that some hard-core slalom course drivers don't care for vaccume secondaries. The previous owner of my old boat had a carb put on w/mechanical secondaries. That 351 was a much stronger pull than my current '95 PS190 TBI. However, it did consume easily twice the amount of fuel.

03 35th Anniversary
03-09-2008, 04:17 PM
The 750 is alotta carb for a stock small block. If your wanting to get to a little more out of it my suggestion would be to re-jet the 600.

I would say vacuum secondaries if most of your time out on the water is spent pulling kids around and doing just a bunch of free skiing.(Less Fuel $$$)

Mechanical if all you do is go out ski your sets and come back in.

EricB
03-09-2008, 06:32 PM
In addition, a 750 cfm is overkill for the 351 engine. The engine can barely pump past 500 cfm in a naturally aspirated form (even at 100% efficiency). Bigger ain't always better.

TMCNo1
03-09-2008, 07:52 PM
If your stoned, you'll never know the difference between vacuum and mechanical!

Wesser
03-12-2008, 01:25 PM
thanks again guys...nice to have a forum where you can ask anything and get answers without sarcasm

03 35th Anniversary
03-12-2008, 08:27 PM
thanks again guys...nice to have a forum where you can ask anything and get answers without sarcasm
Only if you could hear my voice on the other end of the internet..... :D

TMCNo1
03-12-2008, 09:12 PM
thanks again guys...nice to have a forum where you can ask anything and get answers without sarcasm

We'll just try harder, next time! Just be glad you got better than 'C' grades in school or you would catch it!8p

TMCNo1
03-12-2008, 09:13 PM
Only if you could hear my voice on the other end of the internet..... :D


That will be Al Gore's next internet invention!

east tx skier
03-13-2008, 12:12 AM
vacuum and 600. Throw an edelbrock performer intake on there while you're at it. All sorts of fun.

erkoehler
03-13-2008, 12:56 AM
I've heard that some hard-core slalom course drivers don't care for vaccume secondaries. The previous owner of my old boat had a carb put on w/mechanical secondaries. That 351 was a much stronger pull than my current '95 PS190 TBI. However, it did consume easily twice the amount of fuel.

At $4 a gallon....I'll take the newer engines.

jimmer2880
03-17-2008, 08:20 PM
At $4 a gallon....I'll take the newer engines.

I hear you. There are are many things I miss about that boat. But, I'm always glad I have my MC (especially when it comes time to fill it up). At $4.00 / gallon, it wouldn't take long to justify an upgrade :)

TMCNo1
03-17-2008, 09:34 PM
I'd pay $10 gallon just to hear the carb dump mechanical or vacuum!