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1979 242DL - Analog Motoring

I have put about 200 miles on the car since it has been road-worthy and the mysterious "miss under acceleration" has returned. It is the same thing that was plaguing the car when I sold it the first time, but this time I want to get to the bottom of it.
(My old thread for reference: http://forums.turbobricks.com/showthread.php?t=170882)

I pieced together a kjet pressure tester like this: http://www.turbobricks.com/forums/showthread.php?t=289775 and hooked it up to see what I could find. Per the thread, the line pressure should be 65-75psi and the control pressure should start around 20psi and raise to 45-50psi.

Here's a short video to document:
<iframe width="560" height="315" src="https://www.youtube.com/embed/cuZv9qGIi9Y" frameborder="0" allowfullscreen></iframe>

To summarize, it looks like my control pressure is low...the highest it ever gets is 40psi. I can't watch the gauge while driving so I can't exactly see what's happening when the missing occurs, but it doesn't look like the CPR raises the control pressure to the correct level after warming up.

Any thoughts on the line pressure? Is it normal for it to bounce like that?

I am planning on eventually converting the car to LH2.2 and doing a +T so I'm more concerned about the condition of my fuel pumps vs. having the CPR operate properly. I can deal with the miss if it's the CPR, but if my pump is going south then I need to get a replacement...but it seems like the pump is ok.

Also, since Corona centercaps are $$, I put the newer black ones on and they look pretty good imo.
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I'm sure a new control pressure regulator is both pricy and difficult to find. I would dare to say its the pump. Have you checked pressure into the cpr?
Have you checked pressure into the cpr?

Yes, that is part of what I did with the pressure tester. When the valve on the tester is closed, I tested the line pressure which comes in at 65-70psi...in spec according to the Greenbook (64-75psi). When the valve on the tester is open, it tests the pressure regulated by the CPR. Per the Greenbook this is supposed to be 44-50psi after warming up. Mine only gets as high as 40psi so it appears as though the CPR is not functioning properly.

However, I did not hook a gauge up to the fuel filter to check the unregulated line pressure from the fuel pump.

I do wonder about how the line pressure bounces between 65 and 70psi...should the pressure be steady or is fluctuation normal?

Edit: I also checked the flow rate of the pumps and they met the Greenbook spec of >25.3 fl. oz. in 30 sec.
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I tested the pump head pressure tonight by hooking up my pressure tester to the outlet of the fuel filter. As you can see in the vid below the pressure hovers around 130psi. Again, the gauge needle is not rock solid and bounces...is this normal? The pump is virtually silent during this test (the noise you hear in the video is from insects, not the car).
<iframe width="560" height="315" src="https://www.youtube.com/embed/3B8K387EL8o" frameborder="0" allowfullscreen></iframe>

Pic of test setup.

So after all this testing, what have I learned?
-head pressure is 130psi (gauge needle fluctuates)
-kjet line pressure is 65-70psi (gauge needle fluctuates, corresponds with when the fuel pump makes a buzzing noise, see first video)
-kjet control pressure is 40psi (below Greenbook spec)
-fuel pumps meet the Greenbook flowrate spec

Based on that information, it still looks like the CPR is the culprit.

In the end I want to know that my fuel pumps are working properly. Unless I am missing something, it seems like they are operating normally, besides making some buzzing noises when the car is running.

Any thoughts or comments?
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A small update...figured out my "missing" issue, it was an underperforming tank pump. I replaced it with the ipd upgrade pump and it is running strong now. If you want to read through the process of figuring it out, see this thread: http://forums.turbobricks.com/showthread.php?t=170882

Since fixing that I've been putting miles on it and fixing some minor interior electrical annoyances. I've also been giving it the "Goof Off" treatment and removing the black spray paint. It will need wet sanding and buffing as well as some repainting of some spots, but to me, it's better red than black.

Also, I have a growing collection of parts in my basement for a LH2.2/EZK/+T swap over the winter. ;-)
What's the opposite of 'murdering out' a car? 'Community servicing?' I dunno. Great job, nonetheless!

Started the +T process...

Removed Kjet components

Turbo-length exhaust studs installed. Had a heck of a time getting one of the old ones out, snapped off about 1/4" above the head...thankfully my Titan stud removal tool came to the rescue and worked the stud out w/ plenty of PB Blaster.

N/A vs Turbo exhaust stud lengths for reference.

When removing the radiator hoses, part of the upper hose barb decided to stay in the hose...doh! I think I will just run the radiator like this for now and keep an eye out for a replacement.

I modified the bottom rubber support pieces for the radiator/intercooler. I believe they are 700 mounts, but seem like they will be ok for 240 use.

It took some trial and error to find the right left-right position for the radiator/intercooler stack. Based on all the pictures I found online, the new upper support brackets should go back in the same threaded hole that they came out of, however in my case the pass side bracket lined up better with the left-most threaded hole in the slam panel. The fan shroud was pretty close to centered around the fan in this case. I will need to notch my battery tray to allow the oil cooler to fit. As it is now, the cooler gets pinched between the tray and the intercooler. I will make some simple spacers and get longer bolts for the upper brackets.

I have also been working on the LH and EZK harnesses and have most of the modifications complete.

One of the next things I will do is remove the oil pan to have the turbo return line welded to it and a drain for my catch can (my B21 does not have the PCV oil drain in the block like B23/B230s do). Not really looking forward to the pan removal...seems like an annoying task.
It was a good day...the +T runs!

Need to do some shakedown runs before I get into the boost too much, but it is running smoothly so far.

Need a new radiator b/c of the broken hose barb pictured earlier...but other than that no leaks!
Gentle wet sanding and a full clay bar / buff / polish job should work wonders for the old single stage paint, especially on a darker color like this red. After repainting the areas that need it of course.
Here are some more details of the +T process...

The turbo is a Mitsubishi 13C.

Yoshifab fuel pump vent crankcase vent plate.

Ebay catch can and routing (drain hose is not yet attached).

21mm freeze plugs installed to plug the kjet injector holes.

8AN fitting welded to the oil pan for the catch can drain and a 10AN fitting for the turbo oil drain as well as a new coat of paint for the oil pan (it is really red, looks pink in the pic).

6AN fitting welded to the fuel rail and 850T injectors.

940T downpipe adapted to the 240T exhaust I already had installed.

One of the more annoying parts of the swap...making an adapter for the LH temp sensor. I used the kjet thermal time switch port (M14) and used a generic oil pressure sensor adapter and drilled/tapped for M12. Since M14 and M12 threads are so close in diameter I could only tap the hex portion of the adapter and then stacked crush washers to take up the extra space between the adapter and the sensor base.

Passenger motor mount was starting to separate so I replaced with a 240 Diesel mount.

LH and EZK computers installed in the passenger's footwell.
A craigslist radiator fixed my coolant leak and a new fitting fixed a leak at the turbo oil feed. (FYI: PepBoys sells Russell AN fittings for decent prices and can have them next day) Overall the car has been a lot more fun to drive even with the wastegate actuator set with zero preload. I have an intercooled 240T turbo gauge (w/ larger yellow band) at the moment, so I don't know the exact psi the turbo is running, but it goes to 1/2-2/3 of the yellow band. I am keeping my eye out for a deal on a calibrated VDO boost gauge and a wideband O2 sensor before I turn up the boost.

A few things I've noticed so far...

An exhaust leak between the turbo and manifold, the condensation area can be seen on cold starts. Any thoughts on this? I may not have the nuts torqued to spec here...it is difficult to get a torque wrench on the nuts and I went by feel, but they may be a bit shy of where they should be. (Reference: 32ft-lbs + 45deg)

There sure is a lot of junk that gets blown into my catch can...this is after ~200 miles.

Also, on decel I have noticed some decent smoke from the tailpipe...guess with an unknown mileage turbo, I shouldn't be surprised. :)
Looks nice!
Shouldn't the bolts be tightened a bit more after running until its heated up a few times?
Glad to see the car coming together. Nice that the black spray paint actually came off, can't imagine the elbow grease that went into that!