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Mike K's '79 242 Barn Car Revival

I wouldn't get too wrapped around the axle about it

But that's my specialty! :lol:

Just gave the machine shop another kick down the road to get my head off the shelf. I started making my parts list for bits and bobs - hardware for the engine, gaskets, stuff to move the oil filter out from under the header, etc... man stuff really adds up quick.
 
Are you using a stock regulator or adjustable? Is it at the rated pressure at idle? It is possible to "overpower" a regulator with a high flow pump. Basically, the valve is opened all of the way, and it cannot bleed off all of the pressure to what it is supposed to be. Then as you get on it, more fuel is consumed by the motor and the fuel pressure regulator is able to catch up. Which causes it to go back to "base" pressure, which would be more than the regulator is actually rated for/adjusted to.
 
Very nice project!

thank you!

Are you using a stock regulator or adjustable? Is it at the rated pressure at idle? It is possible to "overpower" a regulator with a high flow pump. Basically, the valve is opened all of the way, and it cannot bleed off all of the pressure to what it is supposed to be. Then as you get on it, more fuel is consumed by the motor and the fuel pressure regulator is able to catch up. Which causes it to go back to "base" pressure, which would be more than the regulator is actually rated for/adjusted to.

Here's the one I'm using http://www.summitracing.com/parts/AEI-13129

30-70psi adjustable, 1:1 boost/vac reference so it should be capable of what I'm asking it to do.

I played with this a bit today - I jumped the FP relay socket and re-set my base pressure to 3 bar. With the pump running I put 20psi into the regulator and pressure rose to 4 bar. I put 35psi into it and pressure still rose to 4 bar, no higher. I checked voltage while doing this and I did have a slight drop from the battery to the pump. I put an optima in the trunk and ran the fuel pump straight off the battery, zero voltage drop and got the same results. No matter how much "boost" I put in I hit a pressure ceiling at ~4bar. I also tried to push the base pressure over 4bar with the adjustment and was unable to get it any higher. Hmm interesting.

The fuel filter is almost brand new, and if the pump is functioning properly I'm not sure where I'd have a supply issue.

I did get a bit of good news yesterday from the machine shop about the RSI head. They checked valve spring pressure and found that the spring seats had been sunk .060" which gives me a seat pressure of 95lbs and 205lbs over the nose with the longer bugpack spring. I'm comfortable with those figures so I don't need to get into looking for another set of springs. He's going to check/set valve lash for me and I'll be ready to go. In order to get the ~4cc out of the chambers I would need to bump SCR up to 8.5:1 the head would need to be cut below minimum height according to the greenbook, so I'm not sure I'm going to go that route right now.

Tried to adjust the clutch a bit because I was having a really hard time getting it into 1st and reverse. It doesn't feel like there is any free play as it is though, so I only tightened it a bit. I need to look at pictures of stock clutch forks - do they have a bend forward? Going to watch the fork while someone operates the clutch and make sure I'm not bending it with the heavy pedal effort.
 
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Have you tried dead-heading the fuel pump to see what kind of max pressure it can achieve, pre-regulator? It may be the pump itself causing the 4 bar limit.
 
What do you mean by dead heading? Yeah thought about that, but I thought if the pump was running out of flow I'd see pressure taper down rather than sit solidly at "the limit"

Pinching the return line completely shut still gets me the same pressure. No change with a different filter.

If the duty cycles were 20% lower at the same MAP last year with stock fuel, I'll infer that I didn't have any supply issues there. Everything is different now, but if anything it's much less restricted and the pump is way way more powerful. So I'm left wondering if the hot rod pump is going bad, or where else I'd get a feed problem. I don't have any way to check pressure other than the FPR body.
 
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Guy at aeromotive agreed that something must be going on back at the pump for it to not build pressure with the return pinched. Deadhead (now that I know what this means outside of tie-dye) on this pump should be ~105psi so I'm way short. He suggested I check for an in-tank leak, otherwise it might just be a bad pump. I'll pop the sending unit back out and look at the feed hose. I really hope I didn't lay out cash for a sending unit and a bad fuel pump :grrr:
 
Thanks for the suggestions, cause it looks like I'm buying a pump. Have tested this thing to death and can't get it to make over 60psi (which it does provide solidly). I took the sending unit out and pressurized it in a bucket and found that fuel was spraying out around the feed hose, evidently someone along the way struggled with hose clamps. Tightened them up and figured I had a lucky fix, but it made no difference in pressure. Everything checks out visually, pump sounds fine it's just coming up short. We can't really understand how it would fail/wear out like this but there's nothing else to eliminate.

Looks like the dw300 and the aero 340 are basically the same, but the dw has a 3 year warranty so I'll go for that. I put the aero back in the car so I can drive in the meantime at least.

If I put a brand new pump in and get 60psi boy I tell ya...
 
Got the DW300 in, pretty straightforward although the extra size of these pumps and sock filters make getting them into the tank a bit of a bitch. I lost one float ball getting the aeromotive out, and another jamming the DW in (managed to fish it out with safety wire). The only issue I had was that the DW filter sock has height to it, so at the regular spot in the sending unit the sock was hitting the bottom of the tank. I slid the pump up a bit in the unit and it fit, and was a bit easier to get in and out as well.

Tested the pump and was happy to see that it deadheads past 100psi, so the A340 is confirmed as a bad pump (unless you only need 60psi). Here is my "don't try this at home, glad I didn't splode myself" test rig:

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the DW in the sending unit

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It is a bit quieter than the A340, I can't hear it running outside the car at idle like I could with the aeromotive. Though, I wonder if the noise was partially a function of the fact that the pump was bad/failing? At any rate, I've got proper fuel pressure now and am glad to have that off the list. Of course the map was built around the bad pump, so now it's suuper rich under boost. It'll have to sit like this until the end of the month when I can get a laptop back on it and get a checkup from Dr. Howard.

I finally got the door panels on, which was much more satisfying than it should be. Just really nice to have "finished" doors and not be pulling it closed with fingers hooked in the door skin anymore. I've also never driven the car with a place to rest my elbow! Small victories.

I, of course, broke all 8 tabs off my brown speaker grills back when I took the panels apart. Solved with a dash of two of my favorite ingredients: SEM black paint and DevCon epoxy

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Thanks to Mr. Brown I was able to get the pulls on and I even found an unbroken passenger side map pocket in the shed.

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and "it's clean so I took pictures, pictures"

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Trying to decide what I want to do when I finish the wheels. Keep the all black centers? Black with machined face on the web? Full polish?

Next on the docket: radiator and e-fan!
 
Great to hear your pump issues are sorted.

Your car looks awesome. I like the wheels just the way they are. Black centers compliment the black interior.
 
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