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distributorguy

620 Land Speed Record

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It may turn slightly slower... but with more authority. Great if larger displacement, higher compression, cold out or battery low. Has a distinctive chirp, chirp, chirp when cranking. Some of my L starters are larger diameter but stubby, this one is longer and a snug fit.

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I just ordered one online, lifetime warranty.  1.2- 1.4 KW instead of .8, so much stronger!   In the mean time I bought a stock one from Napa for $48 with a lifetime warranty.  No core charge, so I suspect their rebuild service is going away???  

I suspect this may affect the cranking rpm, so I'll only have to make a quick setting change in Megasquirt to accommodate.  Easy peasy.  Thanks for the help on this one Mike - a lifesaver!

Edited by distributorguy
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Finally some good news!  

The truck is finally running really well - on all 4 cylinders.  I just took it for its maiden voyage under EFI power.   It dove around the lot here a couple times, then drove up onto the hoist under its own power, without bottoming out!!!  If any of you have seen how low it currently sits, that's kind of a miracle.  At its current ride height, the front crossmember under the oil pan would have been "underground,"  as would have been the oil pan sump.  

 

Now to sort out a few oil leaks and a small water leak, then we get into some road tuning!!!   Yay!!!   Dyno day is T-6 days.  

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Oil leaks repaired,  drove the truck up to about 6k last night.  Tuning is getting better and better, looking forward to some more tweaking today/tonight.  We're ready for our dyno tuning session, very anxious to go racing this year!!!   

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Speaking of tuning, I had Brian Rebello up here a few months ago to add a wideband O2 sensor to project truck. It now has a degree of self tuning capabilities. Apparently, this addition allows the system to adjust the cruise level fuel trims. Admittedly, my knowledge of tuning hardware and software is limited, but remembering that just now made me wonder if your system has any self tuning/ self learning capabilities.

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Last evening and the night before we did some tuning - small tweaks manually, and the rest was auto-tune both under light and heavy load.  Last night our driver took the truck into town (local small township) and said its the strongest its ever run, while the tuner did the same and said 4th gear at 4000 rpm was only 100 mph.  I feel very comfortable saying that the ability to street tune has has put us in a better place than we've been thus far.  Auto-tune sure helps!!!  The truck is now parked until Monday's dyno session.  I'll chase a couple minor oil leaks at AN fittings and nut-and-bolt the suspension, but its ready to go play hard!!!

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Glad to hear things are going well for you guys this year.  Looking forward to seeing you on the salt!

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Dyno session Monday night damaged the motor.  

 

Yesterday was spent pulling the motor to see what happened, then converting our spare motor to dry sump and installing our good head/cam on that engine, installing it, and adjusting the tune to suit.  Hardcore 15 hour marathon.  It goes into the trailer tonight and off toward the salt in the morning.  Bummer that we can't set a record because our displacement is now just over the maximum allowed in our class.  I guess we'll still focus on tuning and trying to get at least one more rookie his SCTA/BNI drivers license.  

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Ring lands were pounded, so detonation.  There was no visible trace thanks to the ceramic coatings, but the rod bearings showed the truth.  This may have been related to excess fuel and 2 failed coils, maybe not.  No finger pointing here, just speculation.  I also believe some of the damage could have been from the high oil level at rest in the dry sump system, helping to push debris up into the skirts.  

 

We ended up deciding not to race after arrival.  The conditions were brutally bad.  Rain Thursday caused landslides along the freeway in Salt Lake, softened the course beyond repair.  In order to avoid cancellation, the SCTA held the event for those brave enough to race.  As far as I know, the only records set were "open" records so any back to back completed runs would succeed.  

 

On the other hand, we did run the truck on the same road where the ballast testing was done in the Worlds Fastest Indian.  That was exciting.  

 

 

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I love that scene. His demonstration with the cigar was great.

 

Sorry to hear about your troubles, and to top it off with poor conditions... that sucks.

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...Everyone keeps saying that.  The truth is that cancelling the event altogether would have been much worse.  At least we got to spend a few days on the salt, meet up with old friends, had a photo shoot for a potential calendar and magazine article, and met a guy who's willing to sell his FIA head with titanium valves, complete with intakes and cam towers.  Best of all was the opportunity to tune at the correct altitude.  We could have chosen to run by waiting around for 2 more days, but our best speed would have been 25% lower than what we're capable of with a huge risk of spinning and damaging the truck.  Now we're ready for a new engine plan and go do a test & tune event at Brainerd International Raceway.  

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I have a close friend who is an amazing welder and another with a Sunnen head bench.  Together they were able to fix a couple crushed Ford hemi heads and get them back into service.  Not sure how its going to play out, but the fellow with the FIA head asked who held the record and if he was a "good guy" or not.  I replied "not really" with a back story and he asked for my shipping address.  Its a shot in the dark at this point, but its a possibility.  

 

Also investigating fitting an L18 crank into an L20b so we have more room to overbore and unshroud valves.  I can make bearing shims or see if there's an existing bearing that might fit.  5mm extra room to make up for.  Pinning a shim in the block is no big deal.  Lots of ideas, not a lot of money or time.  

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2 hours ago, distributorguy said:

 Also investigating fitting an L18 crank into an L20b so we have more room to overbore and unshroud valves.  I can make bearing shims or see if there's an existing bearing that might fit.  5mm extra room to make up for.  Pinning a shim in the block is no big deal.  Lots of ideas, not a lot of money or time.  

 

How does this work? you're going down to a 78mm stroke, a shortening of 8mm over the L20B. A loss of 45cc per cylinder. How does going with an L18 crankshaft allow a larger bore?

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3 hours ago, datzenmike said:

 

How does this work? you're going down to a 78mm stroke, a shortening of 8mm over the L20B. A loss of 45cc per cylinder. How does going with an L18 crankshaft allow a larger bore?

I imagine he is not pushing the piston as far up the cylinder. He’ll lower compression that way but it should allow larger valves to be used as well with a larger diameter bore. 

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L18 and L20B have the same stock 85mm bore so they should be able to be over bored the same amount.

 

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I believe what he's talking about is room in the rules to meet the engine displacement, not physical room in the block.

 

Shorter stroke, larger bore, same displacement.

 

How about a billet crank? No shims, but $2000.

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89mm pistons would come out 1946cc with 78mm L18 stroke. Why not just find an L18 block?

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I don't think an L18 block will go 89mm. It would be very thin in spots. For that matter, L20B blocks are very thin at that bore too. Z20 blocks are the best, better even than Z22 blocks (for reasons other than thickness), but the Z20s are getting super hard to find.

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Actually, I take that back. One of the first hot rod engines we ever put in my brother's 510 was a 2150, built with 89mm pistons, a cut down L20B crank and stuffed into an L18 block. I think it had L18 rods. Short rod, long stroke, big bore. Made shit tons of torque, but ran out of juice at about 5000 rpms.

 

The L18 block is a short deck block, so you wouldn't be able to use long rods, which are desirable in a race engine.

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23 hours ago, Ben_upde said:

I imagine he is not pushing the piston as far up the cylinder. He’ll lower compression that way .... 

 

That's why you use custom length rods....

 

Stoffregen, I was afraid of going to 89mm bore on an L18...

Did 88mm with a half fill on the block, and even then, that was scary thin in spots.

Unfortunately, when I went to assemble it, I discovered the machine shop machined all the bores at an angle to the crank, and ruined my spare block.

Been wanting to take the useless thing down to his shop, and epoxy it to the cement right in front of his door, with a note.

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My goal is to use the custom long rods I already have, a custom crank a friend is already working on, and put it back in the heavily modified block I was already using.  

The L18 crank will have the rod journals reground with a custom offset for the bearing size the rods need, not stock.  Smaller main bearings = lower drag.  We did the same with the rod bearings.  There's room to gain stroke, and put us around 1960 - 1970 displacement to prevent needing to tear the engine down if we set a record.  The oiling upgrade on the crank will likely be better than a custom crank, and possibly stronger overall.  I don't know where you'd get a custom crank that's made of quality material like the stock crank for $2k???  Sounds like a Chinese steel thing that looks good but can't take the high rpms we see.

Then I can figure out where the pin height lands and special order custom pistons of a new design.  Lighter, stronger, faster. 

 

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IIRC, back in the day reading about a Ford DOHC build having the crank being turned to use hemi bearings. This reduces the crank/bearing speeds.

 

I like this build as it explores balls to the walls mods that gain even the most minute advantage in power and longevity not seen on street engines..

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