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Member Since 24 Apr 2015
Offline Last Active Yesterday, 05:11 AM

#1566278 Matchbox dizzy testing

Posted by distributorguy on 24 May 2018 - 04:30 AM

They are particularly fussy about grounding, so make sure the distributor has a good ground to the engine, and the engine has a good ground to the chassis/battery.   Replace wiring/cables as needed.  You can crank the engine to test the distributor.  Look for 12+V at the coil + terminal, and a cycling 12/0/12/0/12/0V at the "-" coil terminal when cranking.   Its easier to see with an analog multi-meter.  You have to get the distributor up to about 200 rpm (cranking speed) to get a consistent test signal.  


If it doesn't function, the module is either not grounding OR the pickup isn't working.  I can diagnose the pickup by simply running it through a pulse amplifier on my Sun tester.  Or you can build one using an HEI module from a Chevy distributor.  There are plans online.  Basically the pickup wires to the small terminals, the larger terminals get power and coil - signal.  Ground goes to one of the screw holes on the end of the module that has the small terminals.  

#1564485 Gas/brake pedals

Posted by distributorguy on 16 May 2018 - 04:49 AM

As long as you can pull the brake pedal far enough left so that you can get your foot on the brake or throttle without hitting both, then the clutch can stay where it is.  Ever think of just buying a more appropriate pair of driving shoes?  Boots or shoes with a wide sole are always going to be problematic for driving.   I used to use driving shoe sin my MG Magnette for the same reason, but later made the modification above - moved the brake pedal to the left - and it was resolved.  

#1564484 620 Land Speed Record

Posted by distributorguy on 16 May 2018 - 04:45 AM

We go faster!  Even if we hook up like we're on concrete,  we still need longer legs.  We were capped out at the 2 1/4 mile marker.  Even with a lack of traction, that's where we stopped accelerating.  


The problem wasn't washboard.  As heat rises through the day, moisture wicks up from the clay base into the salt.  (It evaporates in the cooler evenings).  Because the salt base is thin, the amount of water drawn up is huge - and even more influential.  It turns the salt into a slushy snow type of material.  Rutted, wet, greasy.  That's going to continue to happen, unless some miracle deposits a couple feet of salt on top of the clay, or the groundwater levels drop significantly.  Or both.  


The "unofficial" salt report that was released early, well, we all hope its true.  The truth is, it seriously contradicted itself and it was more of a reminder to get your pre-registration in before May 1st.  That saved a few of us $200, as time flies and I almost forgot to register.  Not really, but we cut it pretty close.  

#1562783 620 LWB with wide 18's?

Posted by distributorguy on 07 May 2018 - 06:48 AM

218, come down to  my shop on some Thursday night (Bonneville build night) and see what it took to make our wheel and tires fit (still only 15, but extreme lowering) to get an idea of the amount of fab involved.  Ours included rebuilding the clutch pedal, changing the inner wheel arch dramatically, and changing the clutch throw to be able to function in less space.  


The other issue no one mentioned with wider tires is that tire scrub is already bad, and amplified the wider you go.  This means you'll find yourself steering the car into corners, and steering it back out of corners.  It won't want to "return to center"  the way it used to.  It makes driving a little more of a chore, unless you add power steering.  That's all required so the tires don't rub.  Its doable for sure, but more work than you might expect.

#1556836 Air, fuel and spark, but won't start

Posted by distributorguy on 09 April 2018 - 11:08 AM

No, the salt flat wires are cut to appropriate lengths.  A few hundred Ohms variation on a HT wire is no big deal.  If you have thousands of Ohms difference, then you have an issue.  I like to see less than 1000 Ohms variation within a set.  I think the race truck wires vary by 100 high to low?  It was too insignificant to care much about.  We have bigger fish to fry.  Its like asking if you can run a 90' hose instead of a 100' hose on your pressure washer.  Does it matter???   No, but it likely matters when you put on a 300' hose.  

#1556458 Weber running too lean, can’t adjust enough?

Posted by distributorguy on 07 April 2018 - 11:04 AM

You can likely hear the vac leak you have. I bet its big.  


What is that carb jetted for?  A 1275 MG?  Those jets are tiny!!!  

#1555969 Weber running too lean, can’t adjust enough?

Posted by distributorguy on 05 April 2018 - 08:37 AM

As mentioned earlier, the screw you are adjusting is only for idle mixture.  While the lid is off, read the two jets in the bottom of the carb.  One side (smaller throttle plate side) is the primary and will likely be something like a 150.  The secondary side maybe a 160?  Common trick is this:  if you are at a 150/160, then buy a 155, 165, 170.  Start by going up 5 on each and see how it improves.  Of course this is after you make sure you plugged all the vacuum holes in the intake manifold - its easy to leave one open and you'll be sucking clean air instead of metered air.  

#1555603 620 tension rod bushing comparison

Posted by distributorguy on 04 April 2018 - 11:40 AM

On a lowered truck, you can go with a pretty hard material as wheel travel is already limited.  The greater the wheel travel, the softer you want the material to be.  Or if its really hard, you want it radiused like the washer.  They're easy to shape when they're frozen.   :thumbup:

#1553367 From France to USA : help please!

Posted by distributorguy on 24 March 2018 - 08:07 AM

I once had a customer send me a couple of adult  6-packs via a local delivery service for helping him evaluate a local car.  Hint, hint...  

I didn't even know you could do such a thing!  

#1553366 spark plug for rebello built L "2150" B motor

Posted by distributorguy on 24 March 2018 - 08:04 AM

NGKs are COLDER with higher numbers!!!!


6 would be stock compression

7's are best in 10:1 area

11:1 8's

We run 12's in our 14:1 motor.  


If you call NGK with engine build details including compression, carbs, displacement, etc... they will recommend you likely use one of their race plugs (non-resistor) given the extreme build.  The call is free.  


#1553162 From France to USA : help please!

Posted by distributorguy on 23 March 2018 - 10:56 AM

As rare as 620's are in France, spend up to make sure you get something both complete, and reliable.  You will find that $4000 will not likely get you a really nice truck.  It will likely need maintenance, many spare parts, and potentially some moderate repair work that will be difficult to complete without a good parts source.  Both of those trucks on Offerup look to need mechanical work.  When someone sells a Datsun as a 2L and not an L20b, its obvious they're not really Datsun guys.  I'd be more likely to look at trucks with rebuilt drivetrains and deal with paint after you buy it if you had the option - since you say you're not a mechanic.  Draker's options look better than yours in that respect.  

#1552961 Potential 620

Posted by distributorguy on 22 March 2018 - 08:11 AM

I thought the "notched" bench seat was only on the early trucks?  If this is an early truck in disguise, it won't have the front disc brakes.  That would help explain the hard pedal.  I don't see the coil on the inner fender where it belongs.  Is that bent shift lever a dogleg?   Non-matching glovebox door as well.  Maybe a good deal at half the price?  I'd inspect before walking away.  Look at the ID tag and verify age.  There is also a number stamped in the frame on the front top passenger side near the fuel pump area.  

#1551606 Danfiveten's Joker

Posted by distributorguy on 15 March 2018 - 06:31 AM

Epoxy a penny on the inside of the door behind each hole.  Then you can use more epoxy, bondo , or weld the hole in.  

#1551605 L20b timing help

Posted by distributorguy on 15 March 2018 - 06:27 AM

Split overlap looks an awful lot like both valves are closed so simply watch the 2nd valve open, then close, then bring the timing marks up to TDC.  That's your #1 TDC firing stroke.  

#1550351 Airdam indecisiveness

Posted by distributorguy on 08 March 2018 - 04:38 PM

Now hide that patch with the license plate, and leave the lower valance vents open!