Dan Baldwin Posted March 5, 2003 Share Posted March 5, 2003 Drove down to VIR a couple of weekends ago for an instructor clinic with NASA and a 2-day high performance driving event. BobH shared the car with me. Short story: The car ran great for three days, then on my last run on Sunday, the oil pressure went south. Brought it in, we changed the oil, and lo and behold pressure was normal again. Hit the road, continuing my journey southward, but only got 10 miles south of the track before the death clatter came. Fortunately, Bobby came and got my sorry ass. We took the car to his place in Norfolk the next day and got to work on removing the ancillaries. Took the engine out on Tuesday, and stripped it down for delivering to the shop that will be doing the rebuild. MUCHAS GRACIAS to Bobby for saving my arse and doing more than half the work on the car! Moral of the story: Don't expect to get more than ~50,000 miles and about 50 hard track days out of an L-series engine with a stock oil pan and no oil temperature gauge (though the sensor is in place in the oil drain plug, the gauge remains on a shelf at work). Oil pressure would fall during hard right-handers from day one, so clearly I was living on borrowed time. It's testament to L-series engines and to the guys that put it together for me back in '94 that it lasted as long as it did. This time there WILL be a competition oil pan and I'll run an oil cooler if necessary. Maybe I'll get 100+ track days out of this rebuild! Quote Link to comment Share on other sites More sharing options...
Drax240z Posted March 5, 2003 Share Posted March 5, 2003 Sorry to hear about your troubles Dan... Are you entertaining ideas for modifications, or are you pretty much out of things to modify on that engine? (at least as far as more power goes) Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted March 5, 2003 Author Share Posted March 5, 2003 No new tricks on the rebuild other than the comp oil pan. I will have the pistons shaved flat and notched for valve clearance, and might remove one of the layers of the 2mm head gasket for a 1.5mm to make up for the lost volume and a bit more, maybe aim for a 11.2:1 CR. Other than that, I don't know what might gain me much for a street engine running on pump gas. I'm open to any and all ideers for more powah! Reliability and cost are the two primary concerns, though. Quote Link to comment Share on other sites More sharing options...
z-ya Posted March 5, 2003 Share Posted March 5, 2003 Hey Dan, Sorry to hear about your misfortune . You are probably right, given the HP you are getting, and the number of track events you do, the motor held up pretty good. What exactly failed? Main/rod bearings? Is the crank OK? WIll it need boring? Did you loose oil pressure on your way home? I put an oil temp gauge in my turbo 240Z this winter. The turbo oil pan already has a sensor bung welded in, so I just drilled out the factory sensor, and tapped it for 1/8 NPT thread. I bought an Autometer 2 5/8" gauge, and mounted it in the clock location using a 280Z clock housing. If you want the particulars, let me know. Aside from the orange needle, it looks alomost stock. Keep us informed about the rebuild. Pete Quote Link to comment Share on other sites More sharing options...
gnosez Posted March 7, 2003 Share Posted March 7, 2003 Dan - I always thought you were a $1,000. away from a blown engine or spun set of bearings, running like you do without the benefit of a baffled oil pan or an Accusump set-up. An oil cooler for those fast laps you and your car are capable of would be the final touch to a great protection system. Sorry to hear about all this. Let me know if I can do anything to help... . 3L240 soon to be 3.2L240 Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted March 7, 2003 Author Share Posted March 7, 2003 Thanks for the condolences. I was on the verge of having the engine rebuilt last year when I had the headwork done. But hey, I got a whole season + 1 event out of it! I'll get an oil cooler for it only if the temps are high. I expect they will be, but no reason to spend the money until I know how much cooler I'll need. PS, I'll know more about the specifics later today. The shop is supposedly doing the post-mortem as we speak. JJ, so you're going 3.2. 90mm bore with 83mm stroke, I presume? Quote Link to comment Share on other sites More sharing options...
gnosez Posted March 7, 2003 Share Posted March 7, 2003 Yeah, that's about it with the stroker crank and triple Mikunis. Looking at the TWM fiberglass coolbox and a remote air filter. It's about $100 more than a ITG single unit set-up. Won't get my car on the road until May. Club Race car should be running by late April. Keep us all informed... Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 7, 2003 Share Posted March 7, 2003 I want an oil cooler, for my soon to be turbo swap, but some people prefer high oil temps (270ish) and lower coolant temps. This is not always easily achieved, but this way (theoretically) water and other contaminents burn out of the oil better. Quote Link to comment Share on other sites More sharing options...
gramercyjam Posted March 7, 2003 Share Posted March 7, 2003 FYI: I saw a web page a while back chronologing a 510 racers experiences. It seems he was suffering loss of oil pressure and overheating too but as it turned out, the timing chain was wearing off bits of guide/tensioner and those bits were ending up in the oil filter and elsewhere too I suppose and clogging things up. --John B Quote Link to comment Share on other sites More sharing options...
johnc Posted March 7, 2003 Share Posted March 7, 2003 50K out of a mostly track motor is pretty good. You got your money's worth out of that one. Take a little extra time and send your crank to Jim Thompson. He can easily take 10 lbs out of it without affecting reliability. Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted March 9, 2003 Share Posted March 9, 2003 I'm interested in Knife edging my LD28 crank for my stroker. Does anyone have pics of a finished knife edged crank? I'm curious if there is any particular area to avoid grinding so it isn't difficult to balance after the grinding is done. Dan, an Accusump is a cheap investment if you don't already have one. BTW, are L6 engines internally balanced stock? I was planning on having mine internally balanced anyway, just curious. I wish I had made it to VIR. A few freinds took the Rosen Autosport #39 Sentra SE-R down for some fun. The engine was out of the car the night before the event. We broke it in on the Dyno and made 163 WHP from a naturally aspirated all nissan SR20. That car is strong. It was beating the other cars in the drag race after Oak Tree, and on the front straight in front of the Paddocks. It did have an off track excursion when an over-anxious Steve Harper was trying to pass on the outside line. I know a few of the drivers instructors, Eric Rosen, Joe Andersen, and I think Steve Harper is also. I would be making it down to CMP, but my birthday id that weekend, and the wife would be none too happy. I can't wait to get my Z on the track!!! Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted March 11, 2003 Author Share Posted March 11, 2003 50K out of a mostly track motor is pretty good. You got your money's worth out of that one. Take a little extra time and send your crank to Jim Thompson. He can easily take 10 lbs out of it without affecting reliability. I am more than pleased with the life of the engine, considering the usage and my persisting in running it KNOWING I was losing oil pressure in right-handers. I'll give Jim a call about the crank. BTW, my pistons now have substantial dings in them from the exhaust valves hitting! When I mocked up the head install last year, I knew I was close on intakes (.045"), but my blob of clay musta moved and I didn't get a clearance on the exhaust valves. Now I know! Abacus says the valves and guides are all fine, though(?!). At least they'll know where to machine the reliefs in the pistons! The bottom end will need at least 1 rod and 2 (maybe 3) pistons. Seems three pistons had had their skirts machined for clearance, but 3 didn't. More later, Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 11, 2003 Share Posted March 11, 2003 BTW, are L6 engines internally balanced stock? I was planning on having mine internally balanced anyway, just curious. Yep! Quote Link to comment Share on other sites More sharing options...
Bob_H Posted March 14, 2003 Share Posted March 14, 2003 Well well Danny boy. I haven't posted much of anything since the board swap. However, I finally trotted in to check out the new RB forum. I figured you might post about your dead motor, so I checked here as well. Here is the "rest" of the story. First, I had an absolute blast driving Dan's car that weekend and thank you Dan for offering it. If we can ever get it back together, I might sneak another track event out of him, maybe a time-trial to boot! 1st- the direct comparison from my old 3.1,(which was on the track that weekend as well in a new car), and Dan's. Ours were always built fairly similar with him having a significantly larger cam and initially SU's, now the OER's. His motor does not like anything below about 3500 under load. It bucks. My motor,(or more correctly, Jim's motor now), has much more usuable torque down low and doesn't complain pulling from lower rpm's. The effect is my old motor "feels" more powerful, but falls off a litttle on the top end,(fairly minor). Where Dan's would pull evenly all the way to the RPM limiter at about 7100 or so. Acceleration was about on par with a Z06 down low, but once I got into 4th, the Z06 just walked away. Superior aerodynamics and nearly 400 lb-ft of torque... If I can just convince Dan to put a decent set of brakes on his car, watch out! So here is the update from the shop on his motor. Terminal on the crankshaft and about 2-3 of the pistons. One rod is shot for sure. The #1 let go,(bearing wise), roasted the crank, let the upper portion of the connecting rod,(upper meaning where the bolts hold it to the crank, not up in the piston area), hit the block/bottom skirts of the pistons damaging the pistons. They then scratched up the sides of the pistons pretty bad as they worked on the bore. The odd thing about the block was the rear three cylinders were notched for clearance,(from the upper portion of the lower part of the connecting rod), but the front three weren't. Odd. Ironically, those were the three that hit and caused terminal damage. Bottom line from all this: Don't track extensively if you have a stock oil pan! Pay the money for a properly baffled setup, either Arizona Z, Motorsport Auto, or NISMO. BTW, Dan is getting a great deal on a barely used NISMO pan. The #1 con-rod crank bearing is shot. At a min it would have to go down 30 thou, likely more. For a street motor, no problem. For a motor that will see lots of track time, no way. So a new crank is in order. Also, the #1 con-rod is shot, needing a new one. And 2-3 pistons are needed. The question is do you go with 3 or 6..... It is only money right! And in reference to the valves hitting the pistons, it appers that was from before he had the Sunbelt cam installed, as not one of the valves was bent and all the guides were in good shape. However, he will be notching the piston as a precaution... Really what he needs is a brand new 3.1L short block... It is all just money, keep saying that Dan... BTW, I do need to comment on this from Mudge: but some people prefer high oil temps (270ish) and lower coolant temps I can't imagine any reason why someone would WANT 270ish of higher oil temps. Remember, most often it is measured in the oil pan. It can be up to 30 degrees or more higher in the cylinder head. That means you are approaching or exceeding 300 degrees in the cylinder head! That is pushing even Synthetics. And Synthetics do break down, they just don't leave the nasty sludge that dino oils do. As I understand it, they break down into an ash, and are transported through the oil to the filter. That is one of the reasons why motors pulled apart that are run only on synthetics look so clean. But I digress. I would sugges no more than about 240-250 oil temps. 190-210 is the common max power figure I have heard. As it gets hotter, it is only breaking down...... I thoght it was funny that Dan not only had an oil temp sensor in the pan, but had the gauge. He had just never ran the three wires,(sender, pos and neg...) However, I don't think it was a temp problem, but a oil control problem,(uncovering the pickup after running a full track day and not toppping it off on Sunday, so it was about a quart low). -Bob Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted March 14, 2003 Author Share Posted March 14, 2003 And in reference to the valves hitting the pistons' date=' it appers that was from before he had the Sunbelt cam installed, as not one of the valves was bent and all the guides were in good shape. -Bob[/quote'] Actually, the big exhaust valve dings WERE after the new cam/headwork. The smaller intake valve dings were the only marks on the tops of the pistons before I installed the new head setup last Winter. No fault of Sunbelt, IMO, as they just did the head, not the installation, and I was running the cam ~4 degrees retarded. Anyway, despite the fairly scary-looking exhaust valve dings on the pistons (~.080"?), Chuck at Abacus assures me that all the valves and guides are in GREAT condition. Whew! Bobby, stock Z06s are not to be allowed to get away. We'll see about those brakes after I recover from this rebuild. Quote Link to comment Share on other sites More sharing options...
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