Leon

Drive-drive, pass.

Same here!

When I picked up the Z, the PO gave me a bunch of paperwork and documents along with it, including old manuals. A 1973 FSM was one of them, and despite its ravaged condition it's nice to have. Then, last week I saw an ad on CL for a 260Z FSM! The owner (REALLY nice guy!) drove up to my place last night and hands me not only the 260Z FSM but also a 280Z FSM. The generosity was much appreciated!

Tractive effort curves represent all RPMs, it's basically the engine's torque curve. Hopefully my PM helps! Setting the ratios to match fuel economy and optimal TE at max RPM is probably not possible unless the engine has a totally flat torque curve. A properly done L-series will have a fairly flat torque curve but optimal ratios for max TE and max mpg will still be different. Maybe not by much, but different. Setting gears for mpg will create wider gear ratios (higher load at lower RPM = good mpg) and a deeper overdrive (again, lower RPM and higher load) than something designed for the track. To clarify, the engine operates more efficiently at higher load, a wider open throttle being the main reason. I'm sure you can sense the difference when driving various cars with manual gearboxes. Economy cars are geared noticeably differently from sports cars. My Accord hates accelerating but gets great mpg because of wide ratios. Sounds like your son has a great head on his shoulders and you did a fantastic job of raising him.

I'll PM it to you. Race Car Vehicle Dynamics (Milliken and Milliken) is the chassis bible and Internal Combustion Engine Fundamentals (Heywood) is the engine bible as far as I'm concerned. Both are fantastic books. I hope your son drives the Z responsibly, you're putting a lot of thought and work into this. I like your design intent! Here's a good example of a tractive effort curve:

Wow, Jim! I really appreciate your long response and for sharing all your work. Looks like you have a great plan for your build! I also have a quite involved spreadsheet with dyno plots, gear ratios and tractive effort curves, letting me get the most out of the engine and gears. All of that is thanks to the previous owner, who was my Vehicle Dynamics prof! The tractive effort curves show me the optimal shift points, based on the force available at the wheels. The "perfect" shift is when your tractive effort matches with the gear you're upshifting to. Luckily enough, these engines are internally balanced and resilient to 1st, 2nd, and 3rd order harmonics. Gotta love straight-sixes! As you've implied, the crank and clutch will be balanced individually, and the pistons and rods will be weighed to make sure they match each other. Looking forward to seeing you work and meeting sometime! Thanks again, Jim.

Jim, thanks for the tips! This is actually my first full engine rebuild, so I'm starting fresh here. Balancing is a great thing to mention and something I forgot to ask about. D'oh! If they can balance the crank, ensure consistent rod and piston weights and balance the clutch/flywheel/PP, we'll be in business! Compression will be CA pump gas friendly, i.e. no more than 10:1. It'll be a flat-top L28 with either the modified E31 (depending on chamber size, haven't cc'd yet) or a cut-down P90. I'm more worried about clean ports and big valves than maximizing compression.

Ah, it was in Martinez! Thanks for the rec! This is great info for Bay Area guys. I did some research yesterday, myself. Made a trip to Gotelli's (local speed shop, love that place!) to pick up some Redline for the S2000's oil change. My baby only gets "the best". I BS'd around with the guys and asked for a local shop recommendation that does OHC engines. They recommended Baca's Auto Machine and "Stevie" specifically. They said Baca's does a bunch of Honda engines and pretty much anything else you can think of. It was just 10 min away in South SF so I drove down to the shop and man, it definitely looks like it's been around for 50+ years (current owner later told me the shop opened in '68)! I spoke with Stevie, he's a cool guy and seems like he knows his way around this stuff. What gave me extra confidence was that he's done L-series work before and there was an L block sitting right by my feet, waiting to be worked on! I was quoted $500 for bottom end machining (that's magnaflux/cleaning, boring, crank turning, rod resizing... some of this may not be needed) and $750 for bottom end machining plus assembly. I'd love to assemble my own block, but time is of the essence here! I'll leave myself plenty of time to put the rest of the engine together and into the Z. Now, the only problem is, the crank is still in SLO! I had to leave quite a few parts behind in SLO that we couldn't fit into the 4Runner, Outback, or the Z. Specifically, another block, couple cranks, couple of air dams, etc. I'll keep you all updated, and hopefully this shop comes through!

Gotcha, I've been keeping my eye out for one. I'm not a fan of Cannon's as their throttle rod supports are almost always not aligned, causing throttle return problems. The TWM has beefy cast-in supports that I assume are line-bored straight, plus they don't have a redundant support which can cause binding. Of course the issue can be fixed on the Cannon by removing the redundant (middle) support and using a stiffer throttle rod...

Just quickly review this thread again, and damn you're getting close! I don't know if you mentioned this, but where did you get the TWM manifold? Looks like a nice piece, I like it more than the Cannon.

Oops! I looked it up and need to correct myself: we did indeed get the Primera, but Nissan marketed it as the Infiniti G20 in the States. It only came in 4-door sedan form though.

FWIW, while I don't believe we had a version of the Primera in the US, we do get the Nissan Tiida, although here it is called the "Versa". Also, this is the 3rd gen Focus, with the 2nd gen playing the role of "ugly duckling".

Awesome thread!!!

Hey Alec! Unfortunately, I couldn't fit in single track into my schedule at the time (prof is "Fab" BTW ). I LOVED ground vehicle dynamics. I'm glad the Z is staying in the family as well! Wish I could've build a bike, you still have the scooter? Looks like Texas is treating you well, man. I'm sure you're enjoying your house and 370Z!

You just don't get it... Inline6 is not looking only for a good sound! This is a track car. I guess I can stick a couple of bananas in my tailpipes and call it good, as long as it makes nice noises, is quiet, and I don't "feel" a difference? I'll repeat, I saw ZERO dyno results in anything posted. All I saw were a couple of bar charts (1/4 mile mph and sound levels) with no supporting data posted. They also showed open pipes as being the "fastest", completely going against the other article you posted. BTW, no where did I insult YOU. Supertrapp is a different story... There's no reason to get so defensive when somebody challenges your choices. The only conclusive evidence here would be a dyno test comparing the Trapp to other mufflers. If you're willing to do so, I'd love to see the results from a properly done experiment, whether they back up my argument or not.

Thanks for the tip, Alex!

Precisely John, thanks for clarifying that. A proper test for open pipe vs. muffler would be to make the open pipe's geometry as similar as possible. As John points out, very little info is provided and nothing is conclusive from this "test".

Now that I think about it, I can stop by Gotelli's as well, they're much closer to my neighborhood, and get some recommendations. Maybe check in with Ditos Motors to see who they use too. i know they rebuild engines and that's where I go to dyno the Z.

Sweet, thanks for the tip, Nate! Safe to assume it's these guys?

I've seen the link in post #69 referenced before. I quit reading as soon as he says that mufflers out-perform open pipes. Sure... That alone shows that the test is flawed. Clearly, they are missing how the physics work here. I don't even see mentions of "Supertrapp" on that website. The other link does't work for me and I've seen ZERO dyno numbers showing the Trapp (appropriate name...) results thus far. There may not be a big difference between the "Trapp" and others at a certain point, but what do you think happens when you have a smaller amount of plates? They just restrict the exhaust. This is not "tuning", not even close. What they're doing is killing power and then bringing it back to where it might be when compared to a better-flowing muffler. You seem to carry on a disconnect between exhaust tuning and just slapping parts on. Replacing a restrictive exhaust with a cat-back system that flows better will gain power (depending on original restriction). This is not "tuning". Installing a cat-back system and tuning the engine to "match" the exhaust is not "exhaust tuning". Gaining power over a stock exhaust doesn't say much at all, factory exhausts are not typically designed for max performance, there are myriad strict guidlines for them to adhere to. You're really getting off track at this point. We're talking about the "Trapp" muffler to be a viable alternative for a "mainly" track car. Inline6's requirements have been posted and re-posted. I see no dyno results that support your claims and I refuse to buy a Supercrapp just to test. It's like buying one of those intake vortex generators to see if it helps, some things are just a terrible idea/marketing ploy in the first place. We're not talking subjective things here, sound can be achieved in many different ways. Would I recommend inline6 a 1.5" muffler just because it sounds good? No. It doesn't fit his requirements. As an aside: I am actually curious as to how much a Trapp weighs with all plates installed, vs. say a Borla XR-1 or the like... Everything is in the exhaust sticky, I recommend reading and digesting it about 15-20 times.

Great video and nice diagnosis!

Thanks Clive! I'm actually curious about the filters, so I'll be going to the dyno when it's ready. Hope your Z is progressing well!

Jim, I'm really liking the progress of your build as well. It's well thought out. With that said, I don't know if I'd trust my kid (whenever that happens...) with a car like that! Ha! "Peer perssure points", I like that! I asked her, "so can the Z be in the wedding?" She replied with a "yes", of course, she likes the car and has been very supportive of my addiction (she's the reason I got my first 240Z!). I replied with, "well then I'll just work it into the wedding budget..." She wasn't laughing... I'll keep you guys updated!

Jeez man! We're talking tuning here. Just because there was HP gain doesn't mean there was any tuning involved. A better flowing exhaust can definitely make more power (to a point), nobody is debating that. When we talk of tuning, it's all about pressure wave resonance and to a lesser degree, inertial effects at high rpm. It's all described in the exhaust sticky. Clearly, you either didn't read it or didn't understand it. As JohnC points out, marketing is a clever tool. Looks like Supercrapp did a pretty good job of that... It is clear that inline6 is looking for proper performance along with "streetability". This crosses Supercrapp off the list. Enough said.

As promised, here'e the link for the "new" car: Leon's Other 260Z