scottyp99

Ya know what? I think you may just have the "shakedown blues"! That's what I call it when you make a big change on the car, and have to take it for a shakedown cruise. Super aware of every little noise, every little hesitation or bump, scared something is going to go drastically wrong because you did something stupid, like forget to torque down a bolt........We have all been there, mentally, haven't we? Take a few days and tinker with it, let us know how it goes. Just out of curiosity, how do you set your idle screws? Lean roll? Vacuum gauge? And do you know how to change the air valve opening rate on a Q-jet? It's a useful tuning variable, and it's easy to do.


Keep the shiny side up!
Scott

Tim H

What amazes me is I went to the drag strip Sunday and it was test and tune street tire day and not one car had a quadrajet on it, all Holley varieties.
I guess everybody but 20 people who run quadrajets off this site are stupid in the world?
This is the only site I go to that don't use a quadrajet as a wheel chalk!

BKbroiler

At least people who run Quadrajets are smart enough to know that they are sometimes used as a wheel chock, but never as a wheel chalk.

silver79

Thank you

bobbarry

I find Holleys easier to tune for WOT operation: between easily-changed pumps and shooters, the accelerator-pump circuit is much more easily tuned, and the primary jets are only four screws away from adjustment.

OTOH, for street use, I find it easier to tune the Quadrajet for part-throttle operation, as the tapered needle on the metering rods give you gives you great flexibility for tuning the power-circuit, whereas the Holleys traditionally only let you change the point at which the power-valve kicks in, like an on/off switch rather than the QJet's progressive metering which is more like a dimmer switch.

I haven't tried the Holleys with the new replaceable air-bleeds, which give you better flexibility.

I'd just point out that there are plenty of cars in the Stock and FAST classes that have figured out how to tune a QJet for the strip; it just takes more work.

daanbc

I turned them one half turn rich. As for the air valve opening, I'm leaving that alone for now. Just want to adjust one thing at a time for now. I use to use a vacuum gauge. Now I do it by ear and smoothness of the motor.

QIK59

Pretty obvious (to me) what caused the loss of off the line performance - dont yah think ??

claysmoker

I can't believe it took 3 pages for someone to point this out.

QIK59

Naah it just need's a bigger cam in it to break the tires loose (more power right ??)

If that doesn't work then just rev it up in neutral and drop it into gear - that will definitely do it

Tim81

There is a lot of info shared on this post, as usual some good and some bad. If you are able to set your timing to a perferred setting then the dist. is not a tooth off and moving it a tooth to correct it only means that you have to reset the timing again. Go back to where you started when you could spin the tires on your way to the store. Put the old manifold back on and see what happens, hell like others have already said it could very easily be your cam. Good Luck with your search..Tim

Matt Gruber

Make sure there is no connection between the 2 planes. use 4 hole carb base gasket. NOT OPEN. Open center gasket can lose 50tq!
see article in my sig profile.

daanbc

I do have a "open" gasket. You say to change it to a four hole Quad.? I'll try it. Thanks.. This is an old post. I have since fixed my timing and adjusted my valves. I'll be tuning up the carb. later this month, to set it right, for the mods I have done. Thanks for your input. appreciated.

Matt Gruber

Yes,
both my 61 and 72 were dogs off the line with an open gasket. and they needed 1-2 minutes to warm up on a 40F start, or they might backfire and stall. Now with a 1/4" thick 4holer, i drive right off cold(gently)
see my profile for more info in carb link in sig. Let us know if it helps. Only 3 or 4 have taken my advice. The rest want hundreds of examples to be convinced.

QIK59

Well Shickle am I REALLY this smart ?? (thought I might as well blow my own horn too !) LOL

I knew enough to do this stuff right off the bat when I built the 327 for my '59 35 years ago (in 1978 !!)
This is back before the GPS for intelligence challenged people existed = Internet.
When you actually had to read books, do your own research AND make your own decisions LOL

I installed .005 OS GM Moly Low-Tension hand fitted rings on the original (loose) pistons , stock oil pump/pressure spring, hand fitted crank scrapper and custom fabricated (by me) combination (screen & solid) windage tray.
I only run 10W30 oil !
All this was done to reduce parasitic losses !

I drilled extra cooling holes in the block deck and in the GM SS shim gaskets for better spark plug cooling.

My stock EGR type Q'jet intake is coated on the bottom with Zirconium Oxide (same mat'l as the space shuttle's heat insulating tiles are made of !) for cooler (denser) intake charge

I installed my stock (straight from GM) 300 HP cam 4 degrees retarded for more top end along with the GM dble roller chain.

I also have an electric clutch on my cooling fan (a very slick and very secret sourced set-up) to totally free-wheel the cooling fan !

Jaroslav the Austlander

George Ries

i have the same cam comp web site says works best with 2000 + stall im running 22 to 2400 tci breakaway stall with 3.08 gears and my 76 will roast the tires

vette_20

Hi excuse my ignorance what brand cam is a XE262 i am looking for something with good low down power for my 75 have performer heads and manifild and 600 holley and extractors dont want to wild idle just nice lumpat idle.what is your like .
regards Ian from australia

Tim81

Here some food for thought, tires for these cars are getting harder to find and more expensive everyday, maybe you should quit driving like a 16 year old and leave the good running engine alone..

claysmoker

www.compcams.com

QIK59

Tim,
That's a good one - cracked me right up - you must be an old folk like me LOL !

All this talk about the XE262 isn't getting me pumped up about trying it !
To bad Gruber never wants to reply to me LOL

First thing I need to do is change to Vortec heads - kind of putting that off cause I want to be legal for NCCC competition if they get a convention somewhere I'd like to travel to.

BKbroiler

Ian - Like claysmoker said, the XE262H is from Comp Cams. Regarding the idle, it sounds like a stock cam, really.