stevecritt

iTrader: (3)

How many inches of vacuum are you guys getting at idle? I'm at about 10-11. Just wondering if that is good or not?

89gmcs15

iTrader: (7)

I get about 6 to 8 inches @ 850 ish rpm 6.0 lq9 w/ ls3 heads, 234/250 cam, bigger pro systems carb, lt headers, and a single plane victor jr.

stevecritt

iTrader: (3)

So I'm guessing i'm alright? I'm running a 408cu with ported ls3 heads, cam 234/246 110+2, victor jr and a custom 810cfm carb. I don't know how the different mods play in vacuum?

89gmcs15

iTrader: (7)

I'm not sure if headers and a better flowing intake will cause a drop In vac readings. I'd think so but someone might chime in and correct me if I'm wrong. All I know is if you hold the engine at say 2000 rpm the needle should be stable and not bouncing. I couldn't tune my carb with a vac gauge tho. When it read better vac the carb was way out of wack. I'm sure yours is fine tho with those mods you seem to be ok I'd say

speedtigger

iTrader: (16)

The camshaft and the tune have the most effect. Larger cams of course have less vacuum. More timing will increase vacuum up to a point.

I have a 226/234 on 110 and I have about 8-10 inches of vacuum in gear.

stevecritt

iTrader: (3)

ok. well I have not got the car rolling yet. maybe tomorrow after I bleed the clutch and brakes. but I was just trying to get a little tuning in while I was checking for leaks while the car is on jack stands.

stevecritt

iTrader: (3)

But I just got the exhaust on and vacuum is reading about 12 or so at 1000rpm idle.

speedtigger

iTrader: (16)

Idle vacuum is typically referenced with the car in gear if it is an automatic.

hifi875

iTrader: (2)

I've got 15 in gear at idle. 218/222. .597/.598

stevecritt

iTrader: (3)

car is a 6 speed. Any Idea on what I should be looking for.

Pop N Wood

iTrader: (1)

I have 23 with a stock LS2

speedtigger

iTrader: (16)

With the size of your camshaft, you look like you have a good amount.

S10xGN

iTrader: (11)

It is what it is, every car is different. No sense wasting time and effort trying to peg such a non-standard number. My stock 346" with torquer v.2 and Holley 750 HP pulls 8" @ 750 (but won't idle consistently) there, so 14" @ 950 it is...