pparaska

No doubt the ratios affected the strength as well, but he had it done to home in on ratios for drag racing. In that vein, I've heard that the 3.545, 3.364, and 3.15:1 ring and pinions are stronger since they have more simultaneous pinion teeth meshing than the higher numberical gears.

TimZ, thanks for posting that bit about bumpsteer and having to tune the location of the pivot. I do believe that this has to do with the factory design being a bit hosed and yes there are factory tolerance stackups and cancellations that will make each car different. BTW, I made my pivot points adjustable for just this reason. I can adjust them from 5/8" to 7/8" above the stock location. Independent of that adjustment, I can adjust them out 1/4" to 3/4". These adjustments are entirely independent of each other. They are locked down positively as well. If I need to move the range around I could easily do that a bit too.

But there's more pressure at the grill, supposedly. Funny, Jim Biondo and I were spending some more money talking on the phone one day and he had the following ideas on getting cool air to the engine: -Get a blow through carb attachment that bolts down to the top of the carb air horn. -Take a 4" (or smaller for my wimpy little 327 as he likes to joke ) diameter piece of that nice racing brake cooling hose, and run it from the carb air horn adapter, through a hole next to the radiator. -Take a big K&N cone filter and put it our in front behind the grill and attach to the hose. I might do this, if I can find a place for the hole. [ April 24, 2001: Message edited by: pparaska ]

O.K., I'll take a WAG at this polar moment of inertia (PMOI) thing. Terry's comment is interesting. lenghtening the car does impact the PMOI, since the CG will move forward from the rear wheels if the engine is in the same place relative to the back of the car and the car is lengthened in front of the engine/firewall. The difference being that the engine is now closer to the for/aft CG location, but the front suspension/wheels/bodywork is farther. So it really comes down to looking at the effects of the changes of those things on the PMOI: PMOI(engine)= engine mass (times) Xcg (times) Xcg where the Xcg is the distance from the engine center of mass to the car's center of mass. Do that calculation for both wheelbases and you'll see the number go down since the Xcg is shorter for the lengthened car (lengthened in front of the engine) But you need to see the affect on the PMOI of the stuff you moved forward: PMOI(front stuff) = mass of front (times) Xcg (times) Xcg again, Xcg is the distance betweeen the center of mass of the "front stuff" to the car's CG. So, hack the stuff off just behind the front crossmember, and add the distance you'll move it to the old distance from it's center of mass to the car's CG. You should also calculate the added PMOI of the added section from behind the crossmember to where you cut. Anyway, do the accounting and see what happens. Yes the engine is heavy, but it's close to the CG of the car. The "front stuff" you cut off and move (and the bit you add) is probably as heavy or heavier than the engine, but it's Xcg distance is a good bit greater and it gets squared in the PMOI equation, so it probably has a larger impact on the PMOI. I've kind of convinced myself from the above that the PMOI of the car is going to be greater if you add a section between the crossmember and the firewall, even if you leave the engine in the same place relative to the firewall. BUT, the front tires are now a bit farther from the CG (I'd guess) and they therefore have a greater ability to put a moment or torque about the CG. So maybe it's all a wash? Now I'm confused again.

Hate to sound like a broken record, but this is in the old posts. BUT... JTR is right if you use the stock upper strut isolator - if you put shorter springs on only (not section the struts), you take away from suspension travel in bump and hit the bumpstops often. Two ways to lower (if you keep the tire outer diameter the same): 1) Use a shorter, custom, or modified upper spring perch/isolator/camber plate/whatever assembly above the top coil of the spring. and/or: 2) section the struts to use shorter cartridges (Rabbit front or 85? MR-2 Rear in the shortened front strut tubes, the 240Z front cartridge in the shortened rear strut tube) and shorter springs. Coilovers are often used here, but shorter springs in the stock welded on perch will do the same thing. HTH,

Scottie, thanks, that clears it up - the wheezing I took to mean lower performance and you meant sound.

ZeeZee, welcome. If the power level is 350hp and you can score all the parts to do that for a $4k price (possible), and the car has no rust in structural areas, you might be able to get by with out subframe connectors, if you don't go offroad or road racing with it. The subframe connectors are a weld in affair, so unless you're skilled there, it could break your budget. I'd prefer to have them anyway, but the conversion has been done without subframe connectors and lives with mild use.

quote: Originally posted by Scottie-GNZ: KS, You omitted a key question. Which has the higher HP/torque potential? You must have a decent budget if you are considering building a 3.1L. IMO, outside of a b*lls-out Rebello-type N/A 3.1L, a 3.1L HP potential can be easily matched by a mild turbo setup that would not need expensive internals and it would also have gobs more torque. I know I sound like a broken record, but an L28T with the correct bolt-ons and proper tuning can easily make 300RWHP without putting undue stress on the stock internals. Of course, a turbo engine wheezes compared to a screaming 3.1L n/a and you must be prepared to learn about and manage a turbo setup. I guess maybe I'm dense, but these two paragraphs seem to be at odds with each other. My gut tells me that a screaming 3.1L N/A will put out 3.1/2.8 times (about 11%) more power and torque than a screaming 2.8L. And I also think that I've heard Scottie say that a tweaked (but not much) L28T will put out 300 rwhp. So does a Screaming 3.1L put out considerably more than a tweaked L28T? Confused,

Cool, I was too lazy (it was 2am) to look in the old posts. I didn't realize that a 3.545:1 ratio was available in those.

Scottie, yeah, Mardi is a nice guy and will talk your ear off! BTW, Jim Biondo broke a 240Z stub axle by, you guessed it, wheel hop at take off. He admits he should have stepped out of the gas but was too late. Sure does seem like we need to find a good way to do the R230 swap with a not-out-of-this-world CV shaft solution. Mardi said he could have a bunch (60) custom CV shaft "sticks" made as a minimum, when I talked to him about shorter 280ZXT CV shafts. I guess if we could sell 30 sets (or get someone like MSA or Mike Gibson to buy them) we could design a shaft that used the R230 inner joint and the 280ZXT outer joint, with a shaft length that didn't require disassembling the suspension to get them in/out. I doubt that this solution would be outrageous in price, per set, and we'd be saving money using the R230. Then again, you'd have that gear ratio issue to deal with. I wonder if the outer 280ZXT joint is getting rare. Then again, since we need to adapt the 280Z stub axle and companion flange to the 280ZXT outer flange bolt pattern, maybe another easier solution exists in using the R230 (Z32 TT) CV joint and making an adapter to go from that to the 280Z companion flange. Hmm. That idea of just putting a custom hub carrier in for the Z32 stub axle is looking better all the time - especially if the Z32 TT CV shafts could be used straight up. Oh well, enough rambling. Sometimes I'm glad I have a mild V8 . ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

I've heard of this being done, as this is probably the largest place where the 240Z and the GTO 250 don't agree in proportion. I know a guy with a Daytona Cobra kit on a 240Z and he did the same thing to make it look closer to the real thing. I say, go for it!

Chris, I think the lowest ratio in the R230 is a 3.9 (Q45?). You can get the C-clip from Nissan. But you need to disassemble the diff and carrier to put it in. The question I have is - where is the one that's supposed to be in there. Maybe I've got this wrong, and it's still in the case/carrier, where it's supposed to be and you were looking for it on the axle?

Guys, I have a Tremec TR-3550 5spd. It's stronger than a WC T-5 from the get go, mostly due to wider gears. The shaft spacing is identical or close to it. It came in the 1995 Cobra R Mustang, and is available as a replacement for the T-5 in the Mustang. It shares now design details of the T-5 that I'm aware of. Darkhorse Performance and Forte's are two places that take the Ford form-factor TR-3550 (or the stronger TKO brother) and convert them for use in a GM situation. The details of what I think Darkhorse does to modify it are on my site. Regards,

Fairlady, there are a bunch of threads on this, so I'd search for them, but it really depends on the offset, and the length of spring used and where the coilover is located on the strut. 255/45-17s are the limit with stock fenders on a 240Z. Check out "wheels and tires" link on my site for details. But you really need to put the coilovers on and start making measurements to know for sure. HTH, ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Scottie, I love it when people ramble if it's a good bunch of discussion in there! CV stuff. Did you talk to Mardi at Raxles.com? He's pretty conscientious - he's helping Ford out with the problems they're having with the halfshafts in the Mustang IRS snapping. I'd bet he'd be happy to discuss the type and quality of bearings and cages that he can source. On your CV failure: I'd think that the "stick" (shaft itself) would live but either the bearing or the tripod that connects the 3 bearings to the stick broke. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Sounds like either toe out and/or the rubber steering coupler. A worn out one gives a ton of play. How much camber do you have? If it's less than a degree, I'd think that it would have the numb feeling that John was referring to. Go for toe first, if waiting on the coupler. Just try making up a trammel bar and adjusting it yourself. I made one out of a piece of aluminum tubing I bent up to go under the pan, etc. with adjustable ends (nuts attached to the ends with bolts that screw in/out) that I use on the rim lip at spindle height. But you can make a simple trammel bar from a piece of 2x4 with some plywood pieces on each end to extend up to 1/2 tire height. Mark the tire at the front, roll the car, and measure the toe. Anyway, I'd set the toe to have a bit of toe-in and see if that helps.

I think you'll have trouble with 245s front OR back, without coilovers and or flares. 225s should work (if the offset of the wheel is correct) 235s might fit. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

quote: Originally posted by Mikelly: Pete...Shame on you.... You can't Put Biondo's 5 speed in with the rest of those T5s.... Jim's 5 speed was gutted and had custom EVERTHING done to it, which explains its survivability in that car!!!! (I'm just bustin' chops!) Mike Mike, it's true that Jim's T-5 was gone through at Liberty Transmission, but that was mostyl to get a set of ratios he liked. Before that, it was a WC T-5 with all the Ford upgrades from a place in Michigan that orders them from then BW, and now Tremec (who bought out BW's transmission business). He had several thousand miles and a number of drag strip passes on the WC T-5 before Liberty got ahold of it. Most people can't believe that a WC T-5 could handle that torque. But granted, he didn't have a ton of miles on it or a lot of drag passes on it. Knowing Jim, I bet he didn't hammer the hell out of it either. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Some V8 Zs have used the World Class T-5 with engines in that power level and beyond with success. Jim Biondo's car worked with a WC T-5 (with Ford upgrades) behind a 570hp small block. I have a Tremec TR-3550 behind a mild 327. It has ratios of 3.27, 1.98, 1.34, 1.00, 0.68:1. In a few months it will be on the road (in paint jail now) and I'll be able to report on the driveability of it. They are known to be notchy shifting. These handle more torque than the T-5 (reportedly) and the Tremec TKO is stronger (around 450 ft lbs capable). Again, reportedly notchy. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

quote: Originally posted by DavyZ: That car is a "Primadonna" that was supposed to be the way a "Scarab" would have ended up if the buyer would do all the mods. David Well, I must admit, I thought I know alot about Scarabs, but that's a new one on me. They did have body kits, but they were usually just "california Z" rear fenders a la Jim Cook Racing, and flared fenders up front with an air dam and rear spoiler. BTW, isn't the Primadonna a fairly old conversion/kit car? I remember seeing it in a magazine that I bought over ten years ago, I think. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Stuff like that makes me hate knock sensors. The "hydraulic adjusters" in my Eclipse get a bit noisy and the knock sensor starts hearing them and pulls a ton of timing out. Sounds like you've found your ticket to teh 10s! As soon as you can get some good CVs in the back .

Sounds to me like you have the taurus fan wired to the stock wiring and not straight off the battery connection on the Ford solenoid or the alternator. So when that high current fan turns on, you see the drain on the stock wiring via the Amp gage. What you're not seeing is the probably large current that the alternator is sending to the Ford Solenoid terminal and the battery via the battery cable. Another thing worth mentioning is to make sure the alternator is grounded well to the engine and the engine is grounded well to the frame. On that note, I took no chances and ran a 2 gage (probably should have gone to 0 or 00 gage) welding cable from the relocated battery's negative post to the engine block near the starter. From there I ran an 8 gage ground strap wire to the chassis and a separate 8 gage wire to the alternator case pivot mounting bolt. ALso from that same point I connected the OE ground wire (10 gage black) and ran another 8 gage wire forward to the headlight and fan relays near the radiator. My theory was that the negative side of the circuit is just as important as the positive and a spot welded steel unibody might not be the best conductor over long distances. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Canton and Moroso, and probably others make 6.5 and 7" deep road race pans for the 1 and two piece blocks. Plan to get one of these FIRST, then do your exhaust. The 1 pc seal Vette pan is still available, but I recently found out that the 2 pc seal Vette pan and baffle are NLA! ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

The Richmond 6 speed has a 1:1 5th (like the Richmond 5 spd) but the 6th is overdrive. Check out a Summit catalog.

For the 280Z, I believe the consensus I've witnessed here and elsewhere is to just get the engine, trans, and elctronics from a 280ZX Turbo and transplant it. Cheaper, easier and better result than trying to cobble your own turbo system, generally. As for the RX-7, I'd think if it was a Normally Aspirated engine, you might again be better off getting the engine from a Turbo version of that car. HTH, ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages