73G-nose

Paul, Thanks for the kudos on the car. You agreeing to help out on this is great news. I've been in Baltimore all week, sorry for the late response. I'll get the detailed info you requested shortly...just flew back into Mpls, and boy are my arms tired, etc.

I'll try and contact Paul at Rusch, by email, phone or both. –Thanks

John, I'm in the middle of flyover land, Minneapolis, MN. (my apologies for Al Franken)

Well, I recently completed a down to the bare tub rebuild of this car, (I've had it for several years and raced it previously in a much milder configuration). I did some pre-season testing and initially dealt with some clutch, brake and jetting issues. Since then, those have been resolved, but I have not been able to overcome an ongoing episode of losing valve springs, andor rocker arms. I am not a hardcore engine guy, my comfort zone ends at jet changes, valve lash and ignition timing. Also, I don't hold anyone, or their components at fault for what's happened, I just want to correct what's wrong and move forward. The head is an N42, race ported and assembled initially by Rebello. Cam is a Schneider 300F. Pistons are domed Venolia, 12:1 CR. Once I resolved my jetting issues (weber 45's) the engine began to RPM nicely (I held it under 7K). Finally 3 races into the season it seemed everything was coming together, but the day ended in disaster as I lost the exhaust valve springs on holes 4 and 5. End result, bent valves, destroyed cam and the pistons were nicked but survived. The damaged head was repaired by a machinist within reasonable driving distance who came highly recommended (but had no previous L28 experience). Head was re-assembled with another Schneider 300F, spring pressures set per the cam card, etc. I realize it perhaps should have gone back to Rebello, but there just wasn't time. Since then it's been pretty much the same story, although the problem is now mainly intake valve on hole 2. This past weekend the rocker wear pad and lash pad came off during qualifying. A quick field repair was made (new retainer was needed) and I just made the race, and short-shifted in survival mode to make it live until the finish. One other thing, the cam lobe was getting extremely hot, all others looked happy. I'm not running a spray bar, but I don't think it's a oiling issue...but like I said, I'm no expert. There have been too many well-intentioned but unqualified hands on this thing all season long, and it's time to re-group and get it looked at by a true expert. At the very least the head needs to be redone, but I'm not ruling out shipping the entire package off for some diagnosis and dyno time. –Thanks again

I'm looking for some referrals to tuning shops or individuals with extensive L-series race tuning and cylinder head experience. I'm in need of, and am willing to pay for some professional service in dealing with some recurring valve train issues on my race car (hopefully pictured below) in addition to perhaps some engine dyno time. I'm of course aware of Rebello and Sunbelt, and have heard good things about Paul at Rusch Motorsports, but have been warned that he's typically extremely busy. Can anyone refer some other shops or tuners that they've had good luck with? I'm located in the Minneapolis metro, and am willing to ship components if necessary. –Thanks

Got it started. Had to do some further massaging to the accel. pump linkage, now getting a decent pump shot into the intake. Just as an FYI, the ignition is a new Mallory Hyfire 6AL with matching coil, so spark strength was not one of my concerns. These carbs were purchased through TEP, and I don't know if they were drop-shipped or came directly from their inventory, but wherever they came from it appears they had been on the shelf for quite some time. Thanks for the replies.

Latest update: Removed carb 1 to verify accelerator pump operation...no fuel squirt from pump jets when butterflies pumped. Accelerator pump linkage bound up...lubricated linkage and was then getting fuel squirt during throttle pump. Float level checked out okay, main jets clear. Reinstalled carb 1, removed bowl covers on carbs 2 and 3, verified accel. pump linkage was free on both. Ignition on, pump on...end result same. Intermittent firing but no start...plugs still dry. Still seems to be something amiss in the carb starting circuit. Hoped to avoid pulling all three carbs off the manifold for a teardown, but now it seems unavoidable.

Trying a first start on a brand new motor. Have factory fresh Weber 45 dcoes on a TMW manifold. Fuel pump is a Carter 4070, making 4 psi with pump running. Float level and jets are as delivered, except for a change to 165 main jets. Timing has been checked several times. Fuel is reaching carbs, and is dripping from bowls. Engine will fire, but won't catch...plugs removed and are bone dry. Fuel doesn't seem to be sufficiently reaching the combustion chamber. Using the chokes had no effect. Am I missing something obvious here? Thanks for any and all advice.

Mark, Yes, you're correct. I've since verified it as nothing more than a worn out old standard 5 speed. So much for the previous owners integrity. I never was very informed on the many old Datsun transmission variants, as you can tell. I upgraded to a g-force T5 in my car, and have no plans of reverting back. Thanks for the help...

This transmission came as a spare with a race car I've since parted with, and I've hung onto it as I was told it was an actual Datsun close ratio comp box. Before I decide what it's fate will be, I wanted to verify if it is something beyond the garden variety 5 speed. As you can see from the pics it's in need of an overhaul, or perhaps destined only as a spare parts donor. I don't think it's a "dog leg" style, as it seems to be a conventional 5 speed shift pattern. The tooth counts in black are for this trans...the yellow counts are what I could find listed for a standard 5 speed (page 146 of the "how to modify datsun engine and chassis manual). Assuming I counted correctly (three times) it does appear to be different than the standard ratio. I couldn't find any ID numbers on the case that may have helped solve the mystery. –Thanks for your help

Jon, Thanks for the advice, I was leaning towards the shorter 1436/spacer combo. Actually, the gland nut deal was at the extreme end of the spectrum as far as issues with this car, although a complete rebuild is currently underway. Searching the many previous threads and posts on this site has been a great help during the ongoing rebuild.

I have a set of 240Z strut housings (and we'll just deal with the fronts for now) that had previously been sectioned for a non-adjustable ancient Carrera inserts. The length of the front strut housing from dished bottom to top is 12.5". I'd like to install Koni 8610's, although the 1437's would be a bit too tall at 13", and the 1436's too short at 11.41". Anyone want to venture a guess if the 8610 gland nuts are deep enough to make up the .5 inch overrun on the 1437's...or would I be better off spacing the shorter 1436's from underneath to the proper height (over an inch would be required). Here's where the story really gets interesting...the neanderthal that set this up originally either didn't have, couldn't get, or lost the appropriate gland nuts for the front inserts, so his solution was to slam on the stock nuts (which didn't engage any threads) and just weld them on there. I was able to get them off, but the weld did penetrate enough to ding up the female threads inside the housing. I'm going to try and save them if possible. Fortunately the rears escaped the "weld mod". –Thanks for any advice

Okay, figured it out...I've been told the diesel cranks have a locating dowel at the flywheel end of the crank, which these have.

I have several crankshafts that came as "spares" with a recent race car purchase, and I was told by the previous owner that 2 of them were diesel cranks. I plan to sell one (or both) but want to verify they are actually L28D cranks. Any suggestions on how to do this, or is there an existing thread that might help? –Thanks

Thanks for the links, Jake. I'll check this out further. –Thanks