Daeron

I just had to point at the butt you drew. (I always was mature for my age!!!!1!)

oy... But then again, tony highlighted your * nature and then included a parenthesized exclamation point, which is an old keyboard rendering of an arse.... *(I couldn't actually say anal there and infer it as your nature. Seemed too forward. Woops.) But seriously, we like people who spell things out here when they speak accurately. (Or was that precisely? hmmmm....)

Instant Classic

well, given the nature of my first comment in this thread, I suppose I will field this. I haven't made any posts because most of the details of the matter have dimmed in my memory, but as I recall the blame for the camshaft lobe destruction was about equal parts lack of zinc, and poor metallurgy in aftermarket camshaft blanks. The steel in many aftermarket camshafts (and, presumably any new rocker arm surfaces) now available for flat-tappet engines is not up to the task of long life under intense spring pressures without the zinc additive. A factory camshaft blank, factory rocker arms, and ZDDP additives are three steps you can take to avoid this catastrophic problem that anecdotal evidence suggests is possible. You are the one who has to read the information available, and analyze the anecdotal data available to you, and make the call on what goes in your crankcase. For the record, I haven't driven my Datsun in five years, (oh my god i cant believe its been that long) and when I did I never used anything but inexpensive brand name Dino oils. (Whatever decent brand was on sale.. Typically GTX or Pennzoil, but I'm not picky.)

insert voiceless noises of appreciation here..

75 or 76?

The KA transmission is a direct line descendant of the L6 transmission. Same holds true for each cars' respective automatic transmissions. Incidentally, the auto box is also the same box as the 4EAT gearbox that Subaru has used in almost all of its cars for the last 20 years. The KA fivespeed can be adapted onto the L28 by taking the bellhousing of the L-series gearbox and machining it for a larger input shaft bearing, and then installing that bellhousing onto your KA gearbox. I may be overly abbreviating the process, but in essence, it is that simple. Nosing around should turn up many threads regarding this conversion; I suggest you go to the drivetrain subforum, I think it is a sticky there.

+1. Anyone who says "Don't believe me, go read my source" has no ego to bruise. And as for worrying about what kind of oil you put in a bone stock DD L28.. someone needs to read on why ZDDP is so desirable in our engines. The short version is, modern motor oils can contribute to the utter destruction of your camshaft.

All of your points are still very valid. To be brutally honest, I was thinking of using TB flanges from stock L28 plenums. They all have the egg-shaped hole, even though we have round bore throttle bodies... but it is definitely an item that needs to be addressed. Your comment certainly drove home the reality that there is a stark difference, so thanks for that.

Well, forgive me, but some of us don't get to travel the world and play with 200 mph Z-cars

And I'll drink to that!

I STILL cannot get over the idea of an SU manifold with an EFI flange on it (or injector bungs added) and then two of these puppies, with the skinny primaries feeding into a long intake tract inside a plenum, and the big throats opening to the middle of the plenum. The plenum could look similar to the SU air filter box, with the long tract wrapping around the outer perimeter before opening into the main plenum. Dual-length intake tract, anyone???

I kinda figured, but I always get a nagging feeling that one of these days someone is going to take something I said and run too far with it, into a brick wall. Somewhere in the L-series FAQ and hyperlinked/stickied commentary there will be (repeated) mentions of several books with similar titles. One of said volumes is quoted on the page with the design utility; they all sound like "how to rebuild your datsun OHC engine" and "how to hotrod and race your datsun" and there is a restoration book, and maybe half a dozen great, GREAT reference books. Unfortunately, the titles are all so similar, as well as the general layout of the covers of many of them, that I get them all fuddled. However, that fact (and its inevitable embarassment of the cheese I call my brains) is grossly outweighed by how totally awesome, informative, and generally highly thought of these books are. Enough has been said specifically about each that I tend to just point, and I assume those with the initiative to read them will actually follow the directions and search a bit. If you have difficulty finding them, but are still interested, let me know and I'll dredge up some links.

I thought you might have an injector cooling fan from a 280ZX hidden down there somewhere, giving you an extra electronic supercharging effect You have a link to a thread or a gallery with more pics of the piping? I cannot see enough examples of this being done to satisfy my curiosity.

It won't take you long to get the feel for the car with its changes, and you will be back in "the Z" again. And you will be taking those precious seconds left on the table by fear of the Big Bad Wall back off of your times. But it is natural to assume you're going to baby a new (old) baby for a little while, at first at least.

Speaking of which, I have an old electric Hewlett-Packard Torque Multiplier I'd like to sell, if anyone is interested........ (commence groaning)

Wow. What a bounty of bodies!!!

Am I failing to see something on his hat that makes this red hat something special, or are you saying you are trying to put the bill of a baseball cap onto the front of your car as an extension??? Both ideas sound almost wholly baseless, unless its the right idea... and I'm not certain which one you meant (although I've a hunch its just the ballcap metaphor.) In any case, it sure looks... Exotic. It reminds me alot of the old Porsche racers, in a way that makes me think I oughta hate it.. but I find it mesmerizing....... What I am saying is that I am torn between love and hate, but I've got a biiig grin on my face either way.

The page itself credits where the measurements were quoted from, I believe it was the Honsowetz book but I get the titles of the 3-6 relevant Datsun books all fuddled in my memory. My standard disclaimer when sharing that link is to insist plain and simple that no one should EVER presume parts will fit because someone said they would. ALL TOLERANCES should be checked by the person assembling the motor, even if that person has checked them before. If you don't do that, you deserve to smack your pistons into your valves the first time you fire it up, IMHO. Like I said, thats sort of a standard disclaimer. Usually I have more context (more conversation happening than in this thread) so I can make it sound a tiny bit less dickish... but I think you'll understand I was just being clear.

What he said.

http://www.ozdat.com/ozdatonline/enginedesign/

We are the music makers..... and We are the Dreamers of the Dreams....

I think I was responding to john's bringing it up.. but my thoughts on the triple pipes is just.. where do you PUT them?? One on the driver side, in front of the rear wheel, one behind the rear wheel, and one exiting out the back? Three side by side offset to one side on the back? A triplet in one circular arrangement, centered? One at each side, and one in the center? Remove the hatch, install a pantera hatch, and do three of the thru-the-truckbed "Semi pipes?" My intellectual thoughts on the effects of the design are irrelevant, as they are not informed enough to answer any questions. So you get a little humor instead.

I want to apologize, I somehow omitted to state what I meant to state after posing that (rather judgmental-sounding) question. That was: It starts getting into derivatives, and calculus, and goes far above my head (at least, where it sits now..) but I hadn't intended to leave it hanging out there like a bald accusation. I am certainly no one to condescend; to achieve the rank of "Peer" here is my humble aspiration and I didn't want to convey anything other than: the specifics of a given extractor are tuned literally to the engine, and any more complex understanding than that requires specific research and education (wrenching and reading books, and of course asking questions like these.) Once more, sorry if my mistaken omission caused an insult. For the record, I had excellent skills in math until I started calculus, and at that point decided I had learned enough math for my own tastes, and I could pick this back up later if my path seemed to warrant it. So my answer to my own question is basically, "Far enough to see the light, but not enough to really understand it."

brady:how much math have you taken in school? The reason john is coming off as snippy is very complex and subtle. That reason is, this entire field of exhaust wave pulse tuning is...... complex and subtle. SUBTLE. *I* certainly don't really know enough to ansswer your questions fully, but I think I can get a good handle on why your questions cannot really be answered... A given engine has its volumatric efficiency and its number of cylinders, which are the first variable. We've got siz, so there is one pulse every 120 degrees of crank rotation. Six into one is one single function: f(n)=nXyXa, where n is your torque fat point (I am bluffing here to make a metaphorical point, just bear with me) y is your number of pipes and a is the length of the primaries. when you get to something like a six>3>1 or 6>2>1, there are two or three more steps in that function, and they get multplied together, and exponents are involved, and things spiral out into a multitiude of meaker responses.. you get, instead of tuned for one big fat torque pouint, two, or three, or more torque peaks that are correspondingly less stark, but can be made into a broader, more comfortable vault-like torque curve. I THINK that is sort of the gist of it. There is alot of math involved in even coming close to knowing what you are doing, and that is why John says you need to study a book... because he would need to write that book for you heree and now for you (and I) to really GET this, and I wasn't planning on paying him for that... so we need to find someone who HAS been paid to write said volume, and purchase it and then try, try, try again and THEN we will understand. Thats why all I really think about is pipe sizing and construction quality. When I am in the range of playing with real exhaust tuning, then maybe I will figure these things out with more precision and to greater detail. You get to a point where some things, you just leave it to the guys who are REALLY trying to win races and spending the money to eke it out of their motors, and then ogle it. That last 5% of the power is a b!tch to squeeze out.