Jump to content


Senior Member
  • Content count

  • Joined

  • Last visited

Community Reputation

943 Excellent

About distributorguy

  • Rank
    Senior Member
  • Birthday 09/11/1970

Contact Methods

  • Website URL

Profile Information

  • Gender
  • Location
    Metropolis, MN
  • Cars
    77 Datsun 620, 73 Datsun 620
  • Interests
    Rebuilding classic vehicle distributors
    Racing Bonneville
  • Occupation
    Irish terrier wrangler

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. distributorguy

    620 Land Speed Record

    The track was really, really hard and fast, until mid afternoon. It was hotter than the past couple years, and more humid so the density altitude was higher - nearly 8000' versus the real altitude of 4100. DatzenMike, actually, the exhaust valve is opening at a very fast rate right after TDC, so the exhaust valves are most likely to get bent from hitting a piston - while chasing it down the hole in the first .040" of piston drop. Both valves are parallel to the piston top in most race engines due to the dome design. The 240Z guys from Japan had that happen this year, and managed to get over to JDM in Salt Lake for parts. Rumor had it they were able to get it back together overnight and they might run today.
  2. distributorguy

    620 Land Speed Record

    Well, the truck is back safe in the shop. Tonight we're having a meeting about the next moves. My goal as of today is to swap the street motor back into the truck so we can develop an EFI system, and work out bugs as I make it street legal for local testing. Our 2nd engine may actually be done for next year, but I'll get the current one diagnosed in the next few weeks and we'll move forward repairing it as needed. The valves work as intended, so I suspect the abrupt timing shift actually burned a valve/seat. The other possibility is that we could have shifted a guide since they're significantly shortened to flow more air. We're using custom Manley severe duty valves (ceramic coated), so its got to be something relatively simple. The fact that we jumped timing 30 degrees - that can only happen at the crank gear. Why did that happen? We'll know soon. The 1/8" roll pin in the distributor shaft only holds the retainer sleeve in place. Its driven by a screwdriver blade inserted in the end of the shaft. Since the crank gear appears fragile, maybe its time to add a belt driven oil pump as well, go distributorless, and skip all that fragile crap. All speculation at this point. It was great meeting you Mark! We also had Aaron Kauffman stop by from Arclight Garage - better know from GasMonkey. That was cool. Its such a welcoming race environment, but the race conditions are abusive at best. We'll be back next year.
  3. distributorguy

    620 Land Speed Record

    We made 5 run attempts and only conpleted one. Achieved 98.5 in 3rd gear and things went south. So far we diagnosed half cylinder pressure in #2 via the exhaust valve, the front crank seal spring was pulled up into the timing chain, and the distributor drive gear lost its index. Likely sheared the key at the crank gear? Going home early.
  4. distributorguy

    Blown head gasket?

    I typically go an extra 5 lbs higher on a used head stud to accommodate for stretch. Dangerous game. A torque to yield torque wrench will run you North of $600, but yes they are very accurate. For example, my connecting rods are either 60 ft lbs or 25 ft lbs plus 65 degrees.
  5. distributorguy

    620 Land Speed Record

    Both of my overnight packages arrived. New leaner SU needles, and a bunch more DCOE tuning parts including 3 mm needle/seat combos because 2.5 wasn't big enough, even at 4.5 psi fuel pressure. Another 2 sets of emulsion tubes as well, not that they matter whole lot. Anything to have leaner options out there. They're already installed and we can't wait to hit the road for 19 hours. 🚚 30,000 page views. Who knew??? Hopefully we don't suck ass again this year.
  6. distributorguy

    72 620 barn find

    Bad news on the rust, but at least its not a complex patch. Your ride height looks identical to my race truck. Have you modified the center cross member yet so it doesn't catch on everything you run over? Easy to trim it off and replace the bottom with flat plate. Stiffer leaf springs will prevent the rear axle from banging against the frame. I had a local spring shop make up a replacement set with a higher rate, reverse spring eyes, and set up flat.
  7. distributorguy

    Twin Weber 40 DCOE length

    My Pierce 50 DCOE setup installed is 10" overall, 8" exactly to the face of the carb minus velocity stacks. I removed the power booster and installed a larger master cylinder to accommodate.
  8. distributorguy

    twin plug z24 head. simultaneous plug firing? any info

    I've only spun up 2 of these distributors, and I recall seeing that they actually did fire 5 degrees apart. Nonetheless, You can use a single wire for the primary plug set to fire BOTH coils. This will guarantee that they will fire simultaneously. Jaguar did this on their V12s. One coil for each bank of plugs, fed by the same trigger wire with a simple jumper.
  9. distributorguy

    Z24 intake manifold coolant passage sealing

    I learned the hard way that applying a bit of #x sealant to water ports, even on a head gasket, is ok. I assembled a TR6 motor a few years ago and didn't do this. On the pushrod side of the motor, despite both the head and the block being resurfaced, the gasket leaked oil. Disassembled it all and had to remove a triple Weber setup, glued the gasket back in place, and it sealed. You can say don't use #2 on a head gasket, which is fine, but there are times it would save your butt if you do and there's no down side, other than clean-up during the next rebuild. But at least you won't have to clean up after all the leaks.
  10. distributorguy

    Did You See What This '79 King Cab Just Sold For...

    Go buy a new "mini truck" and they're not only huge, they're $40k starting price. Good buy if its in solid mechanical condition. They're more expensive in the "salt belt" than on the West coast, which still has rust issues. Restore one of these and see what that costs... $9k is a steal for a rust free truck in good mechanical nick.
  11. distributorguy

    Hood trim replacement

    Whatever kind you want to use. That'll work if you like how it looks, and its the correct width.
  12. distributorguy

    620 Land Speed Record

    I know, I know. But here at 1000' altitude, setting up for 13.5:1 = about 12:1 at Bonny (4100-7000'). We were doing short dyno pulls, with the load reduced so we were running about 20 second pulls in 4th, at the very longest. More like 10-15 seconds. There IS risk involved. I don't condone this. But there's more risk in having my drivers never look at the air/fuel gauge and trying to drive through 14:1 or 9.5:1. At least we have a real baseline for what we need. Without that, image how much damage you can do on a 3 mile full throttle drag race? We had 10-11 runs in last year if I recall, and many of them were WAY out of tune. The pistons survived 100%, with only traces of detonation showing, and no real damage to the land area above the top ring (extremely minor pitting that I polished out before re-coating the tops with a better ceramic.) This year may play out differently, but a leakdown test will show the damage if it occurs. Today I have to learn how to use an LM-1 as a datalogger with my laptop. I've always just used it as a "live feed" while driving. Hopefully I can find the software and the cable... Also building the push-start mount for the front of my truck today so we can shove off through 40 mph, and not have to rely on the slightly over-rich emulsion tube rpm range of the race truck. The newest salt report is the the short courses don't even need to be dragged they're so smooth. The long courses have small pressure ridges developing and the salt is lifting as it further dries. A quick drag will make it harder and smoother than its been in more than a decade.
  13. distributorguy

    74 620 Throttle Cable wore thru sheath

    How ever many ground cables it takes to make you think you solved your grounding problem, double that number and make all the cables bigger. Grounding is like a drainage ditch. You can make a nice ditch that allows water to flow, but on occasion you're going to get a storm. Plan ahead and make sure you don't just have something that COULD be functional. How ever much opportunity you have for power to enter the block via ignition, sensors, etc..., you need a minimum of 4X that much volume of grounding to allow unimpeded electricity flow or your throttle cable will continue to heat up. In most cases, factory cars are under-grounded, at least until EFI became standard. 2 cables off the engine the same size as your battery cables are required - minimum. Not old ones that "look good" either. Tear apart your old ground cable to see what I mean. It'll be green on the inside, invisible from the outside. Overlap cables from the battery to the engine to the frame. Feel free to weld a new bolt (head down) to the frame, then use it to fasten ground cables. Then go to the local auto parts store and buy a 6-pack of throttle return springs in the "Help" section. And pick up an assortment of black battery cables with eyelets on both ends. It'll be your best $30 investment. With a little modification, this will fit beautifully: https://www.amazon.com/Mr-Gasket-5657-Braided-Throttle/dp/B001QVTIM8/ref=pd_cp_236_1?pf_rd_m=ATVPDKIKX0DER&pf_rd_p=fcaa6d12-8b2b-4ad7-b277-864b2da79f6e&pf_rd_r=RQ2PDFWH1GZ2X06RC6AK&pd_rd_wg=rc2OE&pf_rd_s=desktop-dp-sims&pf_rd_t=40701&pd_rd_w=k9spN&pf_rd_i=desktop-dp-sims&pd_rd_r=25139553-97e7-11e8-8a63-ad2dc5335592&pd_rd_i=B001QVTIM8&psc=1&refRID=RQ2PDFWH1GZ2X06RC6AK
  14. distributorguy

    620 Land Speed Record

    Yes it is dangerous. But it'll drop 1.5 points when we get out west at altitude. Dangerous games, but we tweak for best power, then alter for altitude with a partial run. Do you run ceramic coated pistons, chambers, valves, and runners in the head? We do, and they work. 😉 The dyno session yesterday sounded worse than Tuesday, but we made better power numbers - by 10 - 23%. The odd thing is that it was "peakier" and our power curve and mixture were still all over the place. That's when I realized the dyno was using an antique Gen 1 LM-1 AFR meter, and a Pentium IV computer. Crap. We made 9 jetting changes and pulls, and the numbers were so messed up that it didn't make any sense. Our emulsion tubes were rich, no matter how lean a set we installed. Then we'd have a rich spot at 4k on every run that would come and go within a 300 rpm range - it would drop into the 10's every time. WTH? Frustrating. What I learned is that our SU manifold WILL be coming with, and it WILL get a chance to run with a few small modifications. Next year it'll be fuel injected. For now I'm off to find a different emulsion tube option that's likely influencing the 4k problem. If anyone cares, out best run was with F16 emulsions, 185 mains, and 130 air correctors, which will likely get changed to 120s.
  15. distributorguy

    Speed Week at Bonneville

    Evening car show in Wendover, UT and races at the world famous Bonneville Salt Flats. Come hang with us in the pits or in line waiting to run at one of the short courses.

Important Information

By using this site, you agree to our Terms of Use.