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defrag010

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Everything posted by defrag010

  1. Again, you're looking through tunnel vision goggles.. Different types of motors and racing use different types of engine combinations. circle track, drag racing, street motors, etc. It's not just about max airflow in CFM through the motor, it's about powerband, the affects stroke and bore have on things like ignition timing/detonation, and the characteristics of the car and how it will be raced. You don't want to put a 4.25" stroke 434 smallblock torque monster in your 1800lb road race/autocross car just the same as you don't want to put a high winding 283 behind a glide in your 3200lb camaro drag car. Absolutely, by quite a bit. De-stroked engines have been used successfully in all forms of racing, from pro stock to nascar for years and years. 331's were BIG back in the 80's, and even the nascar engines of today use very short stroke/big bore engines suited for sustained high revs. What about F1 motors with their 1.5" stroke and 20k+ rpm? Not only do they make more power than 99% of the cars you see on the street, but a purpose built F1 car even with its short stroke will dominate most any non-purpose built car you can throw at it at drag racing, road racing, autocross, and probably most any other type of race. The kind of logic you're using on the importance of displacement only applies to a small section on the Pie chart of racing.
  2. I was up under the back of my 300zx doing some stuff to the rearend, and kind of made a note in the back of my head about what the stock swaybar looks like. Well, later on, I bent down and looked under the back of my 280zx to see if it had CV or u-joint rear, and by glancing at it, the 280zx rear sway looked almost just like the 300zx sway... except smaller. I didn't crawl under the 280 to measure, but does anyone know if a stock z31 rear sway bar can be an upgrade to a 280zx?
  3. nothing wrong with de-stroking, it all depends on the purpose of the motor..
  4. I wouldn't Ever base a machine shop on how pretty it is inside, how good you paint blocks, how talkative the machinists are, or how many CNC machines you have. Machines and neat shops don't mean anything without good operators. Just because a machine looks old, doesn't mean it won't work any better than a new machine. Most machines you buy for automotive machine work will last you 50+ years if you maintain them. Also, most machine shops won't use a torque plate or do anything special if you don't tell them what you want to do. I don't see how you could be mad at that. There are many methods and processes to honing, and there isn't one "correct" textbook way.... each person and shop will do things differently. Some shops might have great results while not using a torque plate so they don't use them, while others say you need them and hone everything with one. You could say that since the shop you used didn't seal off your block and put 210 degree water in and hone it at temp, that they didn't do it the "right" way... not trying to argue, just saying that your rant leaves alot open.... and this is from the point of view from a machinist - who deals with a bunch of customers and rants about what people think we should do
  5. 400 crank in a 305 will make a 330-ish ci stroker, but it's not an ideal power combo due to the bore being so small with that big of a stroke. also, fyi, it was said above.. a 377 is a 400 with a 350 crank. All you need are special bearings, and you can do it with stock parts.
  6. well, i saved the r200/axles, all four corners of the suspension, the ecu, maf, and the engine.
  7. Does a VG30DE have the same mounts as a VG30E ? Can a VG30DE bolt into where a VG30E originally sat? I noticed that grannysspeedshop.com sells RX7--->VG30 mount kits, but they don't mention any differences between the dohc and sohc vg30's..
  8. The MSA type 2 bumper is the bumper that's on the one in your sig.. In the first post in this thread I linked to the MSA airdam that looks similar to the one on the ZX I posted the picture of.
  9. Got me a GOOD deal on two '86 Z31's.. one is a complete car that just needs some underhood re-wiring to run, and the other is a parts car that has most of the fronend chopped off. I'm going to get the good Z31 running and probably drive it for a while, but what I was wondering is what all parts are good to take off of the parts Z31 before I have the scrap yard haul it off? What parts can I use on my 280ZX? I already snagged the R200 and axles for the 280zx, would the 5 lug suspension be worth snagging for use on my 280zx? I took all the black interior out, and I took the engine/tranny out. The car's a 5 speed.. would the clutch pedal assembly and master cylinder work on my 280zx (converting to 5 spd from auto) ? What else should I save off of this parts car before I send it off?
  10. dang, I'm late on this one... but another +1 for having leaky caps in my ecu and a bad PTU. Had a guy rebuild my ecu for 150$, and a new PTU from the junkyard and my old sputtery talon ran like new!
  11. I just got a Z31 and this sounds interesting to do... is the stock Z31 climate control stuff cable activated or electric w/ motors ?
  12. a 351 will take as much power as you can realistically put at it. 1/2" headbolts, and buy some splayed 4-bolt main caps for it w/ a girdle and you will be set to rock and roll!
  13. I'd pay 150$ for them (but take that w/ a grain of salt because I'm a cheapass in general), assuming there would be no problems with them and that they position the engine/tranny precisely. I take it that they are offset to allow header clearance on the drivers side?
  14. I'm sure it would be just like putting it on with the bumper. Do you have any pics of the airdam??
  15. Call me crazy, but I think the G-nose is the ugliest thing to ever be put on a ZX. I'm just trying to find out if the MSA airdam looks anything like the one in the pic I posted.
  16. I saw a pic of a ZX that I REALLY liked. More than a ZX with the type2 bumper. Here is a pic: Now, it just looks like he took his stock bumper off and bolted on an airdam. What my question is, is if the MSA airdam for 280ZX will look similar to the one in the picture without a bumper? Does anyone have this air dam on their ZX?
  17. don't believe it all you want, but I didn't have to clearance much off of the sides of the block, and only about 1/8" off the bottom of the cylinders. The rods I'm using have a 1-3/4" journal and are smaller physically around the big end with smaller rod bolts that sit more flush along with no balance pad, so even with the offset rod throw and smaller journal, the small rod doesn't extend out anymroe than a cunthair than the stock rod setup does. Use a smaller journal, and you can move the journal centerline farther out to increase the stroke without actually moving the rod throw farther out. It's simple math. You wouldn't be able to do this with stock sized journals, which is why I had to use undersized quad4 journals. As for the welds, The process I used was to grind a 3.5" stroke into the short side of the stock rod journals enough to turn them down to about 1.5" total size. Then, I set the crank in the lathe and used GMAW with 70S wire. Pre-heated the crank to about 300F in the gas oven, then locally heat the journal about to be welded up to about 600F. Had the floorsweep use the big propane torch to keep the crank at temp while I was welding, and didn't let it get below 200F. After All of the journals were welded, quickly stuck it back in the gas oven at about 700F for an hour or so. Took the crank back out, and wrapped it tight in fiberglass to slow the cooling rate down. Took about 45 minutes after the crank was cooled to grind the rods out to 3.5" stroke and to size. No cracks, and the crank itself is being heat treated right now and should be back by the end of the week. You're right, alot of people have had bad luck with their welded cranks cracking on the welds due to the stress risers, but if you do it properly you won't get much of that. Also, cast cranks are Much harder to weld correctly than forged steel, so it depends on what kind of crank you're welding on. PERSONALLY, I have had Great results with welded cranks, and have done alot of de-stroked and stroked v8's and v6's that were anywhere between mild street motors and wild setups. I did a 390 steel crank for a guy last summer, welded the rod throws up and stroked him out to 4" from 3.75" to make 415c.i.. His FE put down 450something hp and 490tq to the wheels in his stripped down old 70's shortwide bracket truck. He's been running 11.9's for almost a year at the 450+whp level with a welded crank and nothing has gone boom yet. You knew a company that had alot of welded 22R's go bad.... so what, that doesn't mean every crank that gets welded will self destruct -- because it's all in the process. Plus, this motor I put together.. we're not talking about a 10000002304230horsepower race motor that turns 10K rpm, we're talking about a stroked motor that will withstand as much or more than a stock setup would without ever turning over 6000 rpm. Like I said, I've had alot of success with welded cranks in alot of performance motors I've built, what about you?
  18. i dont know, you could ask him.. http://www.torquecentral.com/member.php?userid=1648 his aim name is apparently sb2rx7!
  19. there's a guy on torquecentral who swapped a SB2 (not 2.2) into his FC rx7... it is a sweet ride!!
  20. lubriplate with oil is my fav, and fyi.. never Ever use moly lube on any bearing surface
  21. Like I said, the only thing gen3's have going for them is a good factory setup and good factory power. That's why you see so many Fbodies going fast.. because it's easy to take an engine that puts close to 300whp down in stock trim, and just put a few boltons and have a 400+hp screamer. I'm not trying to say the SBC has more potential than the gen3, because they both only have as much potential as you are willing to spend money... but the SBC's been around for a while and are proven to be the king of power per $ with a great power potential and a cult aftermarket following. I just get so sick of people saying gen3's are so much better than sbc's just because they are newer and make more factory horsepower.
  22. Mack - I haven't seen a LD28 anything in my life, even with the million different motor cores we have. I was actually going to start messing around with a mitsubishi 4g64 shortblock I had and trying to get 110mm of stroke out of that crank instead of the L28, but it was together and the L28 I had was already apart and I didn't want to tear the mitsu down and clean everything. mopar69 - The larger stroke is a comibination of welding, offset grinding, and re-drilling oil holes in the rod throws. I cut a thrust cheek to match the size of the rods I'm using. I will get pictures once I'm completely done with everything, and whenever I get around to putting new batteries in my camera. It wil probably be a few weeks though, because next week I have a big queue of things to do that will probably take me a few weeks to get done. I tore the shortblock back apart today to try a few new things. I figured instead of just unloading an un-tested experiment, I would build one the right way and test it in my car before I gave it away. For the cylidner wall thickness, I posted the block with 4 posts per side per cyliner (total of 48 posts.. which took forEVER and SUCKED.. drilling and tapping 48 holes), and I plan on partially filling it once I get time and money for some devcon or similar ( haven't decided which filler im gonna use). I'll probably fill the bottom and top half of the block about an 1"-1.5" and fill the area between cylinders so I can still get some coolant flow through the block. I broke down and bought a set of 6 used Probe dished forged pistons in .020" overbore (which will be just shy of 91mm... perfect to use w/ the HKS 91mm headgasket), so I'll be re-honing the block out to size after I fill it. All I have to do is find 6 H-beam rods (preferably used, and preferably that have spun a bearing so I can get them for cheap and re-size them because they have to be resized anyways to fit), and drop the crank off at the cryo treatment shop in town for a nitriding treatment followed by a cryotreatment. I want to see how much nitriding/cryoing the crank will improve the strength and hardness of the welded areas on the rod journals. As for how much I would charge for something like this? I don't know, I had only planned on it being a one-time thing. I was hoping someone would give me a few hundred for the shortblock as I had it w/ the oem parts, but then I decided to improve upon it and keep it to run in my car as a test platform. I only have 2 more L28 cranks and no more L28 blocks, and I can only do this stuff on my free time at work. I could probably build a few more eventually if I come across a few more L28 blocks, but it would be limited to only that unless you can find another machinist to do the same work for you. The cost of all brand new aftermarket/forged off-the-shelf parts, plus the machine work needed to do one, it would probably cost between 2000$-2500$ depending on who would do your machine work/block prep/crank work and what kind of a deal you got on parts. For now, I'm going to do as much as I can to this and run it in my car as a test bed and see how things go from there!
  23. Flathead ford doesn't have as much potential as a sbc because it's a completely different and horrible design vs. the sbc. If your "extremely modified" sbc's are putting out less than 300hp, then there is something seriously wrong. enlighten me, oh engine master with tons of experience, how a gen3 motor has more potential than a sbc?
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