[ultraman]

I had a friend soak a carb last week, he said a spring fell out and was lost in space.will the spring out of an ink pin work under the primary metering rods? thanks.

[pontiac 455ho]

no. you must get a pp spring a ink pen spring is also much smaller. and weaker. and will not enrich under low vaccum conditions. clliff sells them you get 4 new color coded springs for only. 8 bucks. plus 3 shipping.

[67cruiser]

Send me your name and address and ill mail you a new one

[ultraman]

You guys are too kind, I just wanted some input.Will a spring out of most any qjet do? I have a couple of 2bbl later model with torx screws holding them together.I am trying some upgrades out of cliffs book on this one,wish me luck.

[Craig Hendrickson]

Originally Posted by ultraman

You guys are too kind, I just wanted some input.Will a spring out of most any qjet do? I have a couple of 2bbl later model with torx screws holding them together.I am trying some upgrades out of cliffs book on this one,wish me luck.

You might as well ask if 0.78 jet is good enough instead of a 0.65 jet or vice versa (or even more extreme examples).

I suppose you could eliminate the primary metering rods and PPS completely (as Cliff R has suggested before on another thread) and just jet down until it runs OK. That would be smarter. But, then again, you'd have to have a bunch of different jets to figure out what works. Short of an O2 sensor and an active A/F meter...good luck with that.

[67cruiser]

Ive totally illiminated my power piston spring and power piston along with metering rods, run it everday on the street with awesome power!!

[Craig Hendrickson]

Originally Posted by 67cruiser

Ive totally illiminated my power piston spring and power piston along with metering rods, run it everday on the street with awesome power!!

Huh?

I'd like to have "illiminated" my PPS too, but then I'd be in an alternate universe.

Sorry to call you out on a misspelling, but I think you mean eliminated. I think that point is debatable, but if you are happy, then good.

[Cliff R]

Just to clarify here.

Cliff does NOT "recomend" removing the Power Piston and primary metering rods in Q-jets on street applications. It is simply an option, and when set up correctly the carburetor will run flawlessly in all areas.

Our practice here is as follows:

We don't use them in any of our full race units.

We may leave them out on some high HP street/strip cars.

Most of the carburetors that leave here get them.......Cliff

[lust4speed]

Cliff, Your book has a photo on the bottom left picture on page 121. Do the colors listed in that photo match your current spring kit? Do the numbers listed in inches correlate to the amount of vacuum necessary to fully pull the power piston down or something else? Would we go from your orange spring to the black to slightly richen up light throttle cruising?

[Cliff R]

Our springs are custom wound and not the same as the spring in the Edelbrock kit.

At any light throttle cruising the vacuum produced by the engine is really high, and any power piston spring is going to have the power piston all the down, metering rods in the leanest position.

Power piston springs raise the metering rods when engine load requires additional fuel. They all work pretty much the same way, the cut in points being slightly different due to tension/rate of the springs.

One must also consider that fuel delivery increases as throttle angle increases due to the pressure differential, air speed and flow volume across the boosters and thru the venturi area of the primary bores. This is why we are able to set up q-jets to run straight off the jets without a power piston and metering rods right to start with.

Later q-jet designs switched to metering rods with .036" tips, and a different airbleed configuration, leaving very little difference between the upper tapered portion of the metering rod in the jet with the PP down, and the tip in the jet with the PP up.

In any case, we offer 4 springs in our kit. Lightest to strongest, orange, light blue, green, dark blue.

The "cut-in" points are approximate. The orange and light blue are close, around 5-6" and 6-7" respectively, the green is closer to 8-9", and the dark blue about 10-11".

I've tested them quite a few times, which is very difficult testing, as I used a real engine and varied idle rpm and ignition timing to determine the cut in point. I placed a drinking straw on top of the PP, and reduced engine vacuum until the PP moved upward.

In any case, we've been using and selling them for years, and they give the tuner a wide range of options. We put a long green spring in the kit which can be trimmed for custom applications and those who really like to "split hairs" with these things.

Just some advice when it comes to tuning with PP springs. Determine the best jet size FIRST. Then use the APT (later carbs) or change metering rods to get the light part throttle A/F perfect. Then use PP springs for best transition. In most cases, the strongest spring used will provide the best throttle response, and contrare to popular belief, light springs aren't going to provide improved fuel economy by keeping the metering rods deeper in the jets longer, or more often. Engine vacuum is always high enough at cruise this happens anyhow, and time the engine is heavily loaded (heavy/full throttle) more fuel is required and the vacuum timing needs to fall out as well......Cliff

[pontiac 455ho]

i used. the green pp spring. works very well. and cliff. i let you know how the .065 bleeds i orderd from you work once i get them. also. the green spring. is it requierd to cut it at all. be cause i just put it in as it was. seems to work great.