89IROCZ28

iTrader: (14)

I've modified the stock regulator to make it adjustable. But, the range is only 10.5 - 11.5 psi with the stock spring. An off the shelf spring from a local hardware store set the pressure at 16 psi minimum. I thought that was a little high, so I removed one coil and it's down to 15 psi minimum. I'd like to be able to adjust it between 10 - 18 psi or so before starting to dial it in. I'm thinking someone probably makes a spring that would provide that range. In order to look into that I need to know the working length of the spring in the regulator.

Does anyone have their regulator apart (and adjustable) where they can measure & post the maximum length of the spring when it's installed and the regulator is set for minimum pressure?

In case anyone else is interested, here are the specs I have so far on the stock spring:

OD = 0.968 in.
Wire dia = 0.068
Rate = ~8.0-10.0 (estimated - could be as low as 7 and high as 11)
Free length = ~2.55 (when the spring is removed)
Solid length = 0.56 (this is the minimum working length)
Working coils = 5.5
Total coils = 7.5
Ends = Closed and ground

DM91RS

Another IROC with TBI......... At least they could have gave ya some 3.23 gears....

It is a great looking car.

What fuel pump do you have? And why are you needing to adjust the FP?

89IROCZ28

iTrader: (14)

Definitely on the 3.23 gears (it gets my attention everytime someone posts a 3.23 disk rear - there's even one posted in the Cle OH area right now); thanks for the props; stock fuel pump; and just trying to maximize what I've got to work with. Besides ... the ulitmate TBI mods & AFPR projects have been very interesting, learned a ton about throttle body injection, and they have been very inexpensive.
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DM - Just took a peek at your pics ... ditto on the nice looking ride.

DM91RS

Thanks back at ya but my car is a 50 footer...lol. It doesn't take good pic's up close like yours does. It's older than that pic now and needs paint and bodywork.

I had the same car as you drivetrain wise when I had an 89 RS. The two best things I did for it was full exhaust and the 3.23's.

If you have a laptop you could get a cable and download Winaldl and see what effect the fuel pressure changes are doing to your tune. It shows all the sensors also so it's good to have.

89IROCZ28

iTrader: (14)

LOL! Going 50 mph at 50 feet it must still look pretty good!

I have Winaldl, but the laptop I had w/ a serial port needs to be transplanted into a new case. The new laptop doesn't have a serial port. I see people spending $60 or so for the USB version of the cable. I would get a serial/USB adapter if I knew for certain it would work b/c those are half the price of he single purpose cable.

A full exhaust is on the list of things to do when the current exhaust starts to go. The rear end swap will only happen when it's the right piece at the right time for the right price - unless the original one fails.

I know there's more that can be done to these engines to get more out of them (heads, cam, lifters, etc), but it seems dropping in a late model 350 overcomes many of it's shortcomings in one fell swoop. Again ... that would take the right engine, price, and timing for it to happen.

simpson36

I have a spring that goes from 15 to 30

89IROCZ28

iTrader: (14)

simpson36 - 15 psi is the minimum pressure I can get w/ the spring I have installed now. I didn't plan on taking it any higher until I know that I'm running lean at WOT. Where did you get the spring that gives you that range?

simpson36

IROC;

BTW, I had a brand new red IROC the first year they came out '85 I think? I loved that car.

I do a lot of work with performance throttle bodies and I have the springs made for me to my spec. You did a good job measuring the spring.


The stock crossfire spring goes from about 9 to 14. You can set 13.5 safely, but when you approach 14 you are maxing out the adjustment and getting into a situation where you might bind the spring. I don't use those springs, so I don't know for sure, nut obviously you know how to measure the spring and calc the coil bind, so if you do your homework first, you'll be golden.

ONLY because you know how to measure the spring, I'll mention that with an appropriate sized washer at the bottom, you could bump the range . . . but I'll deny I ever said that . . .

I have lots of stock crossfire springs, because I usually replace them. Be happy to send you one.

Just a comment on bumping fuel pressure: within reason, the fuel pressure is only going to have an effect during open loop (and WOT for early Crossfires). Once the ECM moves into closed loop, it is adjusting the mixture based on the O2 sensor, yes?

89IROCZ28

iTrader: (14)

A shiny new red '85 IROC - sweet! I believe I'm the third owner of this one and it just passed 121k mile mark. I'm fortunate the previous owners took pretty good care of it. It even still has the awfull looking rust preventative in the engine compartment. But, it's probably why it's in such good shape.

A lot of work w/ performance TB's?! I just read your crossfire postings last night. Man, that is some awesome work! Your work speaks for itself and your credentials are unquestionable. Measuring a spring is nothing compared to the work you're doing.

I can see why you don't use stock springs. I'm certain I was approaching bind w/ the stock spring and only got a 0.5 psi increase. That's when I knew the spring would need to be replaced. Sounds like you've done some homework spec'ing a workable spring. I found an online resources that given certain criteria, it'll provide specs on an appropriate spring. Besides the obvious physical dimensions, you can plug numbers for the spring's working range and desired forces at each end of the workable range. Check it out here. All I needed was the maximum installed length. I was using 0.500 as the minimum length (before binding). If taking another coil or so out of the one I have doesn't give me what I'm looking for here's the info on what I'm thinking of going w/, but I won't be positive until I have that maximum installed length :
Modifying the stock regulator to make it adjustable goes well beyond shimming the stock spring. As it turned out, adding washers wouldn't have made any difference w/ my stock spring.

Thanks ... I'll take you up on the stock crossfire spring in case 15 psi ends up being too rich at WOT. What do you want for it, incl shipping?

You bring up a good point on the effect of fuel pressure on the mixture at WOT and it seems to be confusing to many people. My understanding is based on the tech articles & postings I've read here, reading I've done on chevy fuel injection, and what makes sense to me. So, correct me if I'm wrong ...

I agree w/ what you are saying if the system provides enough fuel at WOT. The ECM will control the pulse width of the injectors to achieve an optimum mixture. But, if the pressure is too low to provide the required amount of fuel, the ECM could theoretically hold the injectors wide open and the mixture will still be too lean. It's also my understanding that stock configuration errors on the side of being lean and not on performance.

simpson36

To clarify my comment about using washer under the regulator spring. I said that you could change the RANGE of a spring by putting a washer under it, and I also said that this is ONLY if the person doing it knows how to measure a spring and is very carefull not to bind the spring. I do not advocate using washers as a means to adjust fuel pressure.

If you bind the regulator (rear TB) spring on a crossfire, and the car has been modded with a TPI pump, you can burst a diaphram.

I can't comment on the two barrel TBI spring. I have not messed with those at all.

So far, every stock TB regulator I have seen is of an adjustable design. They simply have 'anti-tamper' devices to keep people from using the adjustment. Crossfire (and probably some other) setups use a pressed in cap. You simply pop it out and turn the adjutment screw with a 'double-D' carb adjuster flexy tool.

The two barrel TBs that I have had my hands on all had the adjustment screw brazed so it's a little more difficult. Still, all you need to do is drill out the brazing and then cut a slot in the screw so you can turn it with a small screwdriver. Pretty simply stuff.

I also commented about WOT mixture on EARLY Crossfire. On this specific setup, WOT runs off a table and not the O2 sensor, so any mods to the injectors or fuel pressure will effect WOT mixture. That may not be the case on ALL Crossfire years, or for TBI in general.

89IROCZ28

iTrader: (14)

Yep, I had to drill out the brazed cap to make the regulator adjustable. But, I replaced the stock 'screw' w/ a longer 1/4-28 socket head capscrew that extends almost to the fuel inlet/outlet fittings. That allows the use of an allen wrench to adjust the pressure.

simpson36

Now THAT is a friggin' good idea!!

Question though; the original screw has a 'ledge' or 'ring' if you will, that bears agaist the can bottom in order to push the spring cup upward. How did you incorporate that into a standard socket head screw?

In other words, what does the socket head screw bear against to push the spring cup upward?

89IROCZ28

iTrader: (14)

First, I was careful to use a capscrew that had enough thread - well over an inch. Care must also be taken when selecting the length of the capscrew. It needs to be long enough to provide the range of travel needed and position the head so you can get an allen wrench on it & avoid the fuel fittings. I still had to cut down an allen wrench to get at it.

To recreate the 'ledge' you're talking about, I used a locking jamnut and a couple of very thin nylon washers. A locking jamnut is thinner than a regular locking nut and fits nicely under the cup that compresses the spring. The thin nylon washers create a bearing surface that allows the locking jamnut and capscrew to spin as an assembly. I also tapped that cup for the 1/4-28 thread, so the cup moves up & down along the thread of the capscrew - just like the original pieces.

The position of the locking jam nut is critical. It sets the internal distance of the thread for the cup and how close it gets to the diaphram. You don't want to drive the threaded end of the capscrew through the diaphram when putting it all together. I duplicated the depth of the stock piece and positioned the locking jam nut accordingly. Oh yeah ... in order to thread the cup onto the capscrew, I had to lengthen the slot in the side of the cap.

I think the whole setup cost less than $5 in parts from our local old fashion hardware store.

I might take it apart tomorrow to cut the spring down another turn to see if I can get the minimum pressure down closer to 11-13 psi using my current spring. If I do (or the next time I do), I'll take & post some pics.

simpson36

VERY creative solution! Imprsssive.

I am building some Crossfire pods right now, and I set the reg pressure on the bench, so I'll cut a coil off my custom spring and see where that puts it.

If it's in the range you need, and the cut coil doesn't upset the diaphram, I'll send it to you just for the postage charge.

You deserve it . . great job on the mod!

BTW, make sure to install the cut coil facing down. The diaphram needs the flattened end.

89IROCZ28

iTrader: (14)

Thanks.

When removing the one coil last time, I closed the last 3/4ths of the cut end by heating it a little. It's not closed & ground, but it sits on the cup better than when it wasn't closed. And like you mentioned, I use the factory closed & ground end on the diaphram side of things.

dctrumpet

iTrader: (10)

89iroc...

Have you figured out what psi your spring has produced based on your modifications to it? I have a ton of information about some springs I have, but have no way of putting this information into usable data. I realize I could place each spring into my current setup and measure the minimum and max psi as I have a 255lph (~42psi) fuel pump. That pump is sufficient for me to measure the springs I have. One of them supposedly goes to 30 psi.

Basically, a spring with the following specs yields ________psi in fuel pressure?

OD .975
Wire size .080
Free Length 1.5
Spring rate 19.73
Max Work Load 18.67
Solid Height .4

I guess I could spend $600 on a gauge to measure it, lol!!! NOT!!!!!

Ronny

iTrader: (1)

top down solutions sells a spring that is "stepped up" a notch to offer greater FP. $12?

89IROCZ28

iTrader: (14)

dctrumpet - No I haven't. It's set at the minimum and delivering 15+ psi. I haven't taken it apart again to take pictures or remove another half coil to try and lower that mimimum.

Based on the specs of your spring I think it would generate 19.5+ psi based on the spring rate, the 1.5 free length, and 0.5 compressed length (for a two barrel TBI regulator). So, basically the maximum the spring can be compressed from its free length is ~1 inch. With a spring rate of 19.7, 19.7 pounds should be the force generated. You can check that using this spring force calculator. If you know the range of the installed length in the regulator you can calculate the psi range you can expect.

The question that I would like the answer to is 'what is the maximum installed length of the spring' to determine what the minimum psi will be in order to determine the range of adjustability for a given spring.

dctrumpet

iTrader: (10)

That's what i'd like to know. I have 5 springs that I would like to know more about and I have a number of each of them. The only way I know to figure it out is to install each one in my setup and measure the psi fully open and then measure it fully closed. I would repeat that process with all of them.

I am fortunate in that I have a number of each of the springs in the 4-5 different sizes and a ton of fuel meter covers and regulator diaphragms. So I could have 10 different setups waiting to go and all i would have to do is replace each fuel meter cover with each perspective spring/compression, etc.

What do you think?

89IROCZ28

iTrader: (14)

Sounds like a good plan. Then you could build a chart of the various springs you have and the pressure range.

How different are the CFI & TBI regulators as far as the installed minimum and maximum spring lengths?

dctrumpet

iTrader: (10)

not sure about the difference between the two. All I have is the TBI setups.

dctrumpet

iTrader: (10)

These are the springs I will be measuring and testing to yield their minimum and maximum fuel pressure capability:

OD .975
Wire size: .080
Free length 1.500
Spring rate 19.73
Max work load 18.67
Solid height 0.4

OD.975
Wire size 0.072
Free length 2.00
Spring rate 10.11
Max work load 13.92
Solid height 0.455

OD .938
Wire size .080
Free length 2.0
Spring rate 13.48
Max work load 8.63
Solid Height 0.72

OD .975
Wire size .072
Free length 2.5
SPring rate 7.96
Max work load 13.92
Solid height .53

Each one of these springs will be put into separate fuel meter assemblies with a new reg diaphragm and with the "stock" regulator cover which will allow the spring to be compressed to it's "normal" stock height. This should allow me to find the minimum fuel pressure that each spring is capable of.

Next, I will install the same springs in to separate fuel meter assemblies with new reg diaphragms and each one will have an adjustable regulator cover. I will compress the spring to it's max without binding. I will then install them on my bird and measure the fuel pressure. This should give me a reasonably accurate reading for the max fuel pressure that each spring is capable of.

It will be a fun little project. I know others on here have done this before which allows them to sell their 18psi springs, 3-30psi springs,etc. For this reason I will not publicly post the data as I don't want to undermine their work and their business. If you would like to know the final data pm me and when it is completed i will share with you what i feel is necessary.

Thanks!

89IROCZ28

iTrader: (14)

Sounds like a great project and I'm very interested in the results ... PM sent.

dctrumpet

iTrader: (10)

some preliminary information.

spring:
.975 OD X .080 X 1.5 Length

the top of the spring when place on the seating surface of the regulator diaphragm (metal ring) sits 1.462" (picture 1) above the mating surface of the fuel meter. So any spring will be .038" below the mounting surface. Not that this info is important.

Once the spring is placed over the diaphragm i placed the reg cover on it. As the cover rests on the spring it's mounting surface is .533" (picture 2) from the mounting surface of the fuel meter cover. This means this particular spring will be compressed .533" when the reg cover is screwed down. Obviously, each springs initial compression will be different, but the overall compressed height once completely installed will be the same for all springs.

With the reg tab fully open I measure the distance the tab moved when it's fully closed. That distance is .303".

So, the stock regulator that has been adapted to be adjustable moves .303" which means any spring will be compressed .303" in that type of regulator.

so....

spring is 1.5" long and is compressed .533 when the reg cover is mounted on top. This means the installed length of this spring is .967" prior to it's compression. So, this will be the minimum psi available for this spring. This .967" initial compression will be the same for all springs with this particular regulator cover.

Next, I compress the spring via the adjustable screw and it compresses the spring another .303". That is a total ending height of .664" which is the max fuel pressure this spring is capable of in THIS regulator cover.

I know of guys who remove the tab from the reg cover to allow more compression. I don't think that is a good idea as it can bind the spring, etc.

CONSTANTS: for all springs
.303" all springs will be compressed this amount via adj screw on this reg only (Jegs, etc may have a different compression rate)
.038" spring sits below mounting surface (not significant)
.967" will be the installed height of all springs with this reg cover

When this spring is installed it's starting height is .967" and final height is .664"

dctrumpet

iTrader: (10)

Ok here it goes. Should we rename this thread to "TBI Myth Busters"? LOL

Spring size .975 X .080 X 1.5 which was included in the black stock adjustable reg cover purchased from an eBay store that stated 10-25psi.

Well, time to bust the myth, lol.

This spring when installed in the fully "open" position yielded 10.5psi and then I removed the fuel meter cover assembly and adjusted the tension to fully closed it yielded 18.5psi.

I did this 3 separate times to make sure and every time i got exactly the same results. It MIGHT be possible to yield slightly more psi if the spring was capable of being compressed more in this setup, but unfortunately the spring is close to being maxed out regardless.

I have a 225lph fuel pump which yields ~42 psi. So, it's not my pump.

The reason why i took the fuel meter cover assembly off is because it is virtually impossible to adjust when installed. I also have a Jet and two other adjustable FPR and they are ALL impossible to adjust while on the vehicle. It is quicker and much, much easier to just take the dang thing off to adjust. I know the four main guys on here and eBay, etc will comment on this, but I want to hear the TRUTH from everyone else who purchased any afpr that mounts in the stock position....

I have a 225lph fuel pump which yields ~42 psi. So, it's not my pump.

So this setup is 10.5psi to 18.5psi

dctrumpet

iTrader: (10)

Ok, step #2... A different spring!

Size of spring: .975 X .072 X 2.5

I repeated the EXACT same process with he EXACT same reg diaphragm and EXACT stock adj regulator cover.

This spring yielded 11.5psi minimum and maxed out at 19psi.

I have three two more spring to try out. The dimensions are listed in a previous post on this thread.

This particular spring was purchased "online" and stated it was 18-20psi when placed in a "stock" non-adj regulator.

My next project with these two springs will be to place them in a stock cover that is non-adj. This will tell me EXACTLY what the springs will yield in the "stock" position.

It would be interesting to see what a .080 spring yields that is 2.5 long.

I will repeat ALL the steps in Jet's and the "other" guys adjustable regulators. I will use the same springs and I will test these units with ALL the springs available online that state a certain PSI rating.

The reasons why I am doing this:
1. I wanted to gain a little more knowledge.
2. I have purchased items online from the "top guys" out there and the products were NOT what they were supposed to be.
3. to help others with perfomance upgrades and finding the right spring that yields X, Y and Z psi ratings in stock reg covers and others.

So, based on the two simple experiments that i just performed I find that the stock reg covers that are made to me adjustable can only yield certain results based on the minimal compression. In my opinion in order to yield up to 25psi with a modified stock reg cover one must have a MUCH stiffer spring. The stiffest spring I have found "online" thus far has been a .080 wire thickness.

Yep, I'm on the hunt and I will keep you all updated.

The funny thing is when i am done with my project I won't even have one of these installed, lol.

I am going to use the Aeromotive 13301 and remove the reg diaphragm and spring and place a custom block-off plate with a custom made viton gasket.

I had about 50 of these made by my machinist. So, I will let you know how that works.

My setup will be running the 4327 injectors @30psi. It will be about 380hp, etc.

dctrumpet

iTrader: (10)

Has anyone else gone through this?

dctrumpet

iTrader: (10)

No one? Just me and 89iroc? LOL

Daves03

where are you getting the springs at i might throw a new one in my maro the next time i rebuild the throttle body. around here ive been told you couldnt buy the spring and it dosent come with a rebuild kit.

dctrumpet

iTrader: (10)

I have got these spring from a bunch of different sources. Most of them have been as a result of purchasing the adfr from sellers on eBay or buying individual springs from others who state a certain psi range.

I am in the process of still testing the springs in "stock" regulator covers that are found on 80% of our TBI cars.

I am also in the process of trying to find a distributor/manufacturer of the
springs. I have asked every single person who has claimed a certain psi range if they have tested it on varying applications. Most can't or wont answer me and the most i can get out of them is "well based on the available data this spring should yield _________...."

SIDE NOTE:
Bunch of crap in my opinion. We at TGO pride ourselves on friendship, helping one another out, precision in performance, etc, etc, etc.

You see the results above. The results don't lie. In a nutshell, all I want is honesty and ethical business practices. When a spring is stated to be 10-25psi and it's sold with an adjustable fpr it SHOULD BE 10-25psi. RIGHT? Well, i tested it as shown above and it's inaccurate!

Anyway enough on my whine and moan session!!! LOL!!!!!!!

dctrumpet

iTrader: (10)

My goal is to find springs that yield certain psi in a NON-adjustable "stock" fuel pressure regulator. Obviously, it's a little more complicated than that, but my experiments will hopefully get really close.

I am finding out that most of the guys on here don't have the time or money to spend $40-80 on an adjustable regulator and spring that doesn't yield what it says it is supposed to and once installed can't adjust it easily anyway, lol. Like I said before I have 6 adjustable fuel press regs. Pretty much everyone that is readily available. I wanted to find the best and easiest to adjust while it's on the vehicle.

Unfortunately, GM screwed up with the design of the TBI regulator setup. It's not the after market guys fault. I know they are doing the best they can in manufacturing an item. I give them credit.

I like what Holley has done with their TBI setup. The regulator is on top and easily adjustable. I don't have the capabilities, but I would love to see someone take our fuel meter covers and redesign them, but that takes a lot of time and a lot of money just as designing the regs that i have.

89IROCZ28

iTrader: (14)

dctrumpet - This has turned into a great thread. Great job on determining the range of those springs, too.

It seems the estimates on the min psi are pretty close. But, you're getting 1-2 psi more than the estimated max.

The next time I take my regulator apart, I'll take some measurements to determine the min & max lengths of a stock regulator that has been modified. On mine I had to extend the slot for the tab in order to reassemble it. I didn't intend to extend the adjustable range more than the stock factory screw to avoid hitting the diaphragm.

dctrumpet

iTrader: (10)

.975 X .072 X 2.5 yields 12psi in a stock non-adj reg

.975 X .072 X 2.0 yields 10.5psi in a stock non-adj reg

.975 X .080 X 1.5 yields 11.5psi in a stock non-adj reg

.906 X .087 X 1.8 yields 29psi in a stock non-adj reg. This spring is a new spring found in a marine vac-compensated regulator assembly.

.906 X .087 X 1.8 yields 24.5-30+++ psi in the marine regulator setup. Instead of the conical shaped spring seat found in our stock reg covers this spring seat is cupped and the bottom of the reg cover has a tamper resitant adjustable screw which does allow this to adjust. As you can see that marine spring in it's assembly yielded a minimum of 24.5psi. My inline gauge only went to 30psi and it was buried, LMAO!!! It no long worked after this test!!!!!!! LOL!!!!

.867 X .064 X 2.45 yields 10-16psi in the black adj stock regulator. This spring came from a brand new ACDelco reg assembly.
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I am going to get more of the .080 springs, but in 2.0 and 2.5 lengths.

89IROCZ28

iTrader: (14)

I wonder what GM's intentions were w/ the design of the TBI regulator? Obviously it's designed to be adjustable, yet they prevent that by brazing the screw. I wonder if they fix the installed length or actually test them to achieve a specific pressure?

The answer to those questions will affect what pressure will be obtained w/ any particular spring in the stock unmodified regulator.

dctrumpet

iTrader: (10)

I have taken apart about 25 regulators from all sorts of applications. I have noticed about 4 different "stock" spring sizes, but that the ONLY difference i can see. The regulator "tab" is in the exact spot on all of them.

89IROCZ28

iTrader: (14)

Dave03 - After modding my stock regulator to make it adjustable and basically reaching the max & only gaining another .5 psi (11.0 - 11.5), I decided to start looking for alternative springs.

I found what I was looking for at my local hardware store. This is one of those well stocked, 'we have almost anything', old fashioned hardware stores - it even has the original wooden floors! It was right off on one of those displays w/ a couple dozen spring of various sizes and types.

Here's what I purchased for around $5 and got two springs in a pre-packaged plastic bag:

Century Spring Corp (CSC) - #C752 - 15/16" x 2 x .080

I couldn't find that number on CSC's website, but I found the following specs that appear to be that set of springs:
With this spring the minimum psi of my modded regulator was 16+ psi. A little higher than I was hoping for w/o knowing exactly what pressure the basically stock engine needed. Based on the specs, I would expect 19-20 psi max.

Because the minimum pressure was a little more than I wanted, I removed 1/2 a turn from the spring and reclosed the end as best I could. The result was ~15 psi minimum. I haven't taken it up any further for a couple of reasons. First, as I mentioned, I'm running a basically stock L03 and it surely doesn't need a whole lot of fuel to produce the 'whopping' 170 hp it puts out. Second, I'm still running the original stock fuel pump w/ 122k miles on it. No need to make that old biddy work any harder than it has to until other mods call for more fuel.

With all that said, it seems to have a little more on the top end than it used to. But, until I can do some data logging I won't be able to tell if I'm running lean or not.

dctrumpet

iTrader: (10)

Again, our TBI setups are from the factory set to run 9-13psi. Those are "acceptable" ranges according to GM. I believe that GM just put in what spring was available at the time of assembly as long as it yielded somewhere in that neighborhood.

We all know that going from 11psi to 12.5 can be a major change in performance. So, don't ask what their intentions were, lol!!! It's GM....
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That's exactly one of the springs I have

dctrumpet

iTrader: (10)

I have that exact spring, but have not tested it as of yet.

89IROCZ28

iTrader: (14)

I think if someone drops that $2.50 spring in the stock non-modified regulator they'll get ~17-18 psi.

dctrumpet - Did you test that one out yet?

[edit] - Oops! I didn't realize you already said you haven't tested it yet.
[edit] - Watch the bind height on that spring in your setup.

dctrumpet

iTrader: (10)

I just found a piece of paper from yesterday that showed I placed that spring in the black stock adj fuel press reg. It's minimum was 11.5psi, but when I closed it down to full pressure and placed it back on the vehicle the vehicle wouldn't start, lol. In fact, I couldn't close it all the way i could hear and see the spring binding.

I actually have 20 of those springs. Like you I found them at a hardware store in a bin. I got all of them for about a $1 each, lol. The only problem is that the spring is not ground flat on top and bottom. This may have caused some issues as it did not seat solid.

dctrumpet

iTrader: (10)

All the other springs that I have are ground flat. This is the exact spring from one of the guys I bought the afpr from. I measured it and went to the local store and found them. Not many springs that they had, but 4 packs of five i was excited. Now i just have to grind them down to work.

89IROCZ28

iTrader: (14)

The CSC spring I mentioned has it's ends closed from the factory, but not ground flat, and it's been working in my regulator since I started this thread.

I just noticed that I previously misstated the spring I'm using is closed & ground. But, it's definitely not ground, only closed.

dctrumpet

iTrader: (10)

Here is the spring and a comparison

dctrumpet

iTrader: (10)

Another view

dctrumpet

iTrader: (10)

Anyone have any input?

89IROCZ28

iTrader: (14)

dctrumpet - I guess we now know what happens when the spring in the regulator binds, eh?

As long as a spring sits straight on both ends, it should be fine.

BTW - I put my car in storage for the winter this week. So, I won't be doing anything with the regulator until spring. I feel pretty good about the AFPR modification and running 15 psi. I'd like to upgrade to a heated O2 sensor next year and when I do, will incorporate a lead to monitor the signal when I install the wiring to accommodate it. That's most likely when I'll get back into the working w/ the regulator again.

dctrumpet

iTrader: (10)

When you do upgrade let me know. I can get some phenomenal ones for a lot less than what you will find online. The ports are much larger thus allowing more exhaust gases. I have bungs as well if you need them. I get them right from the manufacturer. Don't worry they're not Bosch or ACDelco, lol.

dctrumpet

iTrader: (10)

I purchased more springs of the exact same dimensions as listed about, but with higher spring rates and max load capacities.

Going to repeat the same steps as above sometime soon. Obviously, results will be slightly changed.

fcukit33

i know its off topic but where can i find a wire to down loaD from a 92 rs cuz everything i find on the internet only works for odb2 and mines odb1

89IROCZ28

iTrader: (14)

Something like this? http://www.aldlcable.com/sc/details.asp?item=daewoo