Hey all, it's been awhile, busy with an addition on my house. I was wondering if anyone has a seller/part # of a stiifer spring for the TBI FPR. I have the VAFPR, currently maxed at like 25-26 psi, BBC TB 90 pph's, would like to get close to 30, I already have a shim in the spring to get it that high. I searched and saw other post about getting a stiffer spring, but from where?? Thanx.

I wished that I had answer for you as I'm looking for some alternatives also. Seems like something simple like a spring we should be able to find in a industrial supply catalog. There needs to be a better variety of choices I believe.

DM

I think that Lon from Top Down Solutions (TDS) carries a 30 psi spring. Maybe check with him.

GM has a regulator from the '94-95 trucks that has a 28-32 psi spring.

RBob.

I believe this source was suggested some time ago:

McMaster Carr

McMaster-Carr

Yes and yes.

Yes, Lon carries a stiffer spring.

Yes, industrial supply, is where Lon got the spring from originally, HOWEVER, he modifies them a bit.


Contact Lon.

ok then. I have acces to Mcmaster-carr things as we order from them often. I'll have to hit his website I guess, to get his email addy and what not. Thanx for the replies guys.

I thought of McMaster Carr as well as Graingers as we use both.

This is copied directly from Lon's spring page.


-----Top-Down Solutions tested the stock spring (orange in color) that comes with the GM 17113186 vacuum adjustable fuel pressure regulator (used on GM TBI equipped engines) and found the spring rate was too high. We were unable to adjust the fuel pressure below 18 psi at WOT (Wide-Open Throttle). Swapping this spring for the stock spring (tan in color) that came in the non-adjustable fuel pressure regulator wasn’t acceptable either. This spring was found to be too low of a spring rate. We were unable to adjust this spring beyond 13 psi at WOT. This aftermarket spring is an ideal solution, It is rated at 15.5 lbs/in. and will give you an adjustment range from 12 psi to 20 psi at WOT. The spring is zinc plated to provide years of corrosion protection.-----

So unless he carries another that I did not see this does not go to a high enough pressure.

And to modifiy a spring? If you can change it you can mod it unless you only have an axe and stone for a tool kit.

If I new the lbs per sq in of the spring that is in there, I could go by the diameter and length of the spring and get one from the mcmaster-carr catalog. I could even get one a few coils longer at the same rating and shorten it to stiffen it up. Just wondering if anybody had a few spring ideas. I know fast355 has had some high FP on his TBI's. I also have a vortec FP from a centrifical LS1 blower kit that was on my friends Silverado SS. I could probobly use that and get more FP and volume, with the same spring in th VAFPR.

Basically, you have to measure the area of the diaphram and regulator, and from that and the springs rating, you can calculate the peak pressure near coil bind. Gets you pretty close to what it can actually do so long as the spring doesnt yield and remains linear.

Well, I just have to get some sort of scale and measure the springs pressure. See if I can get some sort of measurement, then a few springs to use. I'd rather get close the first few tries then buying 40 springs and 80 attept later I have it. That would be a PITA. When I find a suitable replacement I'll let yous guys know. I email Lon from top down and he recommended the one that is in the article, which of course isn't a high enough pressure.