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  1. Vacuum Advance Explained

    I came across this explanation on the workings of vacuum advance on The"B Bodies Only" website. It's authored by "Revhendo" and I found it worth sharing. For those of you interested....... This was written by a former GM engineer as a response to a similar question on a Camaro board: As...
  2. More vacuum or front bias?

    Suspension - Brakes - Steering
    I have 4 wheel disks on my 68 Firebird but can't lock up the brakes. It stops ok, better when have some speed or first hit the brakes. But best case the passenger rear will lock up a little. New master cylinder and vacuum booster, stock automatic proportioning valve. 383 doesn't make much vacuum...
  3. Vacuum advance / Chevy 235??

    Now I´m baffled! Trying to get the 235 run better and just noticed something that I don´t understand. You know, there is this basic vacuum line that goes from carb to dizzy. When you rev the engine then the vacuum should suck air from that tube and pull the advance and the dizzy moves counter...
  4. Unknown Vacuum Device

    Hotrodding Basics
    Hi, I recently acquired a new OLD truck (1986 Chevy K10) with a custom engine that i don't know a lot about. Currently I'm trying to figure out what this vacuum line is doing (see pic attached). any help is appreciated! thanks
  5. 4160 carb help

    Hey y'all, I bought this Holley 4160 600cfm vac. secondary carb. It looks like someone tried deleting the vacuum function because the hole for the diaphragm was sealed up and there was a screw on the throttle linkage for the secondaries that was adjusted all the way to open with the primaries...
  6. Engine Vacuum After Cam/Intake Swap

    Hello everyone, I have a question about my manifold vacuum reading dropping a decent amount after a cam/intake swap. My original set up was a comp 282s cam (235/235 @ .050" & 282/282 advertised, with .521"/.521" lift with 1.6 rockers, 110 LSA) and a RPM air gap intake with a 2 inch open...
  7. Holley carb won't idle

    Hotrodding Basics
    Hello there guys. last week I found my head gasket had blown out on my SBF 302. So I tore it down replaced the head gaskets, intake manifold gasket, and changed all of the fluids. I fired it up and it runs only if I stay on the throttle. as soon as you let go of the throttle it dies. I did...
  8. new booster with poor vacuum

    I was helping my friend install a brake booster on his 65 charger. After changing the old manual brake MC and adding a new booster, we bled the brakes. still had a soft pedal. so we bled the MC on the bench, and bled the brakes again. felt good to me, but still no brakes. after a week of...
  9. Elgin camshaft question.

    Hi everyone, I just have a quick question(s) about a certain camshaft I would like to put in my motor for a daily driver 1980 c10 long bed truck. The motor is a crate gen1 350 sbc with an edelbrock 1406 600cfm carb and stock th350 transmission. I'm planning on installing an Elgin E1785PM...
  10. Snap16


  11. Vacuum hookup on T-400 transmission?

    Transmission - Rearend
    I was wondering if some had a picture of where to hook up the the vacuum modulator to the manifold? I replaced the transmission in my 89 suburban with an th 400 and need to hook up the vacuum modulator but not sure where is the best place to hook it up at. a picture would be nice.:) thank you...
  12. hello :)

    Introduce Yourself
    Hello my name is Julie Ann, my rieds call me Jules, I just wanted to thank you for the information on this website. It has been very helpful!!:)
  13. Vented Gas Cap?

    General Rodding Tech
    I have striped down some old smog componants in a recent rebuild including a vac canister that had hoses comming in from the gas tank. What should I do with the hoses and will a vented gas cap work for the lack of Vac to tank.
  14. SBC 406 Help/Validation on low Vacuum Reading @ Idle

    General Rodding Tech
    Hi I am needing a little validation on a SBC build. I tuning on an 88 S10, and have a steady 8" of vacuum at 950 -1050 rpm. The cam is fairly large solid flat tappet. The specs are below. I think I am OK, but would like some opinions. S10 weighs 3100 with driver SBC 406 = 9.81 compression -...
  15. Hello from Norway!

    Introduce Yourself
    Ahoy! I'm a 20 year old guy from Norway. I've been into cars since I was 2 years old and after I got my driver's license the interest has just grown. I currently have a '79 Pontiac Grand Prix sitting in the garage which I will try to get into OK shape before the summer so that I can use it as...
  16. Starter kickback problems

    Hey guys, got a 1980 454 motor in my 59 apache. Its got starter kickback 99% of the time I start it. Checked timing with advance disconnected and set at 10 deg BTDC, kickback happens whether is ported or manifold vacuum. I got to the point where I figured it was the starter, replaced it and its...