scooter Posted July 20, 2014 Author Report Share Posted July 20, 2014 If the timing looks like its bouncing around at high rpm, maybe ill go crank trigger, but my datsun experience has shown that there isnt much spark scatter. Compared to v8's anyway. Maybe ill do a comparo for you guys to see if the multiple sparks at low rpm cleans it up more than just using the matchbox. As for fancy ignition things, im looking into spark retard for start and when the bottles on, msd makes such thing :) Crank trigger and coil packs MAY be down the road. My current fears are bending a rod or snapping the z22 crank Quote Link to comment
datzenmike Posted July 20, 2014 Report Share Posted July 20, 2014 Huh? Explain? The 6 cylinder EI sparks at least to 7K on the zx. For a 4 cylinder that would be over 11K. If the timing looks like its bouncing around at high rpm, maybe ill go crank trigger, but my datsun experience has shown that there isnt much spark scatter. Compared to v8's anyway. Maybe ill do a comparo for you guys to see if the multiple sparks at low rpm cleans it up more than just using the matchbox. As for fancy ignition things, im looking into spark retard for start and when the bottles on, msd makes such thing :) Crank trigger and coil packs MAY be down the road. Later CAS for the Z24 used a spline between the drive spindle and the dizzy to eliminate the slop of that screwdriver and slot design. My current fears are bending a rod or snapping the z22 crank If it wasn't mentioned get the KA oil pump, it's 13% larger and has high volume output. Shim the pressure relief spring to give 10 PSI for every 1,000 RPMs you plan to run and call 7k your red line. You want to go higher get custom rods. 1 Quote Link to comment
scooter Posted July 20, 2014 Author Report Share Posted July 20, 2014 Oh yeah i have a new ka oil pump, thats an intresting drive spindle. Hmm.. When its due for a freshen maybe ill put some h or a-beam rods in it. Its hard to find aftermarket ones in l20b length. Pics soon. Quote Link to comment
datzenmike Posted July 20, 2014 Report Share Posted July 20, 2014 On April and on '85 720s with throttle body injection. (easy to tell by the two wing nuts holding the air cleaner on) Also the '86-'89 D21 Hardbody with Z24i engine. All have CAS and need more precise ignition and crank location for emissions and EFI. Quote Link to comment
scooter Posted July 20, 2014 Author Report Share Posted July 20, 2014 Are the drive spindles the same length? This has caught my curiosity Quote Link to comment
datzenmike Posted July 20, 2014 Report Share Posted July 20, 2014 From tip to tip they are 173mm or 6.8125" I have some without the spline that are the same length so not sure what they are off of... maybe L20B/Z20/Z22 Quote Link to comment
banzai510(hainz) Posted July 20, 2014 Report Share Posted July 20, 2014 I just say to get 180hp as you claim crank fire the way to go. and maybe 50mm carbs. My L20 I had in a better 510 I ran a long time ago just cut out at above 7K. its the slop in the worm gear and the weights /spring set up. is whats the issue. The trigger part im sure can go very high as for the MSD I wouldn't even think about putting it in as it will make your car less reliable. get with Byron 510 on the realm as he is good and will give good advice if you don't know him already Quote Link to comment
DISLEXICDIME Posted July 20, 2014 Report Share Posted July 20, 2014 After 8000 the stock distributor drive will fail you will need the Nissan comp brass oil pump drive I kept my l18 under 8000 with the occasional blip to 8500 and it held up fine on the stock shaft Quote Link to comment
Z-train Posted July 21, 2014 Report Share Posted July 21, 2014 I just say to get 180hp as you claim crank fire the way to go. and maybe 50mm carbs. My L20 I had in a better 510 I ran a long time ago just cut out at above 7K. its the slop in the worm gear and the weights /spring set up. is whats the issue. The trigger part im sure can go very high as for the MSD I wouldn't even think about putting it in as it will make your car less reliable. get with Byron 510 on the realm as he is good and will give good advice if you don't know him already 25+ years with MSD on everything I own and one distributor magnet failure. Quote Link to comment
scooter Posted July 21, 2014 Author Report Share Posted July 21, 2014 Main point with the msd is it allows nitrous retard and start retard. I can go from a 50 to a 200 shot, im starting with 50 of course. Quote Link to comment
flatcat19 Posted July 21, 2014 Report Share Posted July 21, 2014 Danger to manifold, yo! Quote Link to comment
datzenmike Posted July 21, 2014 Report Share Posted July 21, 2014 Main point with the msd is it allows nitrous retard and start retard. I can go from a 50 to a 200 shot, im starting with 50 of course. I have to assume those custom pistons are forged??? Stock ones are about 84% aluminum and 16% glass and brittle. Quote Link to comment
scooter Posted July 22, 2014 Author Report Share Posted July 22, 2014 Yes theyre forged 2618 alloy and theyre built for a 150 shot. Custom made by carrillo. Quote Link to comment
scooter Posted July 22, 2014 Author Report Share Posted July 22, 2014 Standby for more pics, i gotta drive out to the machine shop now, spent today fixing the alternator mount on the truck as it cracked in half!. Tonight was spent out on the boat :) Quote Link to comment
datzenmike Posted July 23, 2014 Report Share Posted July 23, 2014 .... and you ran more piston to cylinder, and ring end gap too??? Cause those forged slugs will swell with the heat. Quote Link to comment
scooter Posted July 23, 2014 Author Report Share Posted July 23, 2014 Oh yes like lots of other performance pistons they have ring end gap formulas for your application. At nominal bore they have 3 and a half thou piston to wall clearance. With cp stuff, ive given them a half thou over nominal bore and seen great results. Not enough to cause rattle when cold. Thats off the top of my head, i dont have the spec sheet in front of me. I could have gotten the pistons graphite coated or anodized, but i figured if i was coating everything looking for power, then the thing would end up alot more extreme. Its allready way beyond what i originally wanted to do, i was just going to do ka pistons and a 32/36. We'll see how it goes.. Im not intending to run this thing long period of time before freshens. So probibly next spring will mean some real rods, maybe a chromemoly flywheel.. See how it goes first Quote Link to comment
datsun 160J SSS Posted July 25, 2014 Report Share Posted July 25, 2014 do you have a part number for those CP pistons .very nice Quote Link to comment
datzenmike Posted July 25, 2014 Report Share Posted July 25, 2014 The graphite coating reduces friction. You can get the very top ceramic coated. This is like a layer of insulation so heat is trapped in the combustion chamber where it does work. Maybe 3-5% increase in efficiency if the combustion chamber is done too. Everything adds up. Quote Link to comment
Z-train Posted July 25, 2014 Report Share Posted July 25, 2014 Have you CC'd the heads and calculated CR? Quote Link to comment
Son_of_a_Datsun_Guy Posted July 28, 2014 Report Share Posted July 28, 2014 I'd be interested to see what kind of numbers you get from this thing. Mine is a 2.1L frankenmotor (Z22,U67, .520 or .540 lift cam can't remember which) with around 10:1 compression. Only running SUs but my butt-dyno says it's in the 130-145 range. Getting it dyno'd soon hopefully along with another friend's car with a very similar motor with dual Mikunis. The big displacement you're going after should make the thing a torque monster that pulls hard for a long time with those Webers. Quote Link to comment
EricJB Posted July 29, 2014 Report Share Posted July 29, 2014 Same crank and rods. KA pistons. Same isky cam,(z196) springs and retainers Closed chambered head w/ 44 intakes in 39.7 seats, 38 exhaust cut down to 37.5 in 33.3 seats. 16lb flywheel. 1 3/4 merged header w/ megaphone. Old mallory dual point with pertronix ignitor. MSD 6al / blaster 2 coil. Weber 48 DCOE's. No dyno slips, but the truck runs 13.60's at 94mph. Wallace racing calculators says 150 to 175hp. Don't know if that's flywheel or rear wheel. Don't even bolt that header up. Take the time to make one, or have one built. Sadly, no one makes a decent header for our cars. Just that "one size fits all" POS. Don't feel bad, I have one too. Stock head gaskets don't cut it either. Even with ARP studs torqued to 70 ft lbs. I haven't found an MLS for a z24, so I am going to try copper. Quote Link to comment
scooter Posted August 11, 2014 Author Report Share Posted August 11, 2014 Thats a bad ass header! My question for you is what did you end up running for lash caps? I ended up with .300's with that isky cam. With the 45 mil intakes i had to remove alot of material to try and get rid of the valve shrouding. Also if you order 280zx valves from ferrea they are shorter than stock u67 valves, i ended up moving the seats deeper into the head and completely reworking the chambers. Compression wise i ended up at 11.1. I think whatever horsepower i lost in compression i gained in eliminating chamber shrouding. My valve job im keeping secret as ive been using it on oval track motors with great success. Next refresh its getting 6 inch billet rods and a new set of pistons, i feel the rod strength is going to hold me back, along with not getting tool steel dlc coated wrist pins. Quote Link to comment
scooter Posted August 11, 2014 Author Report Share Posted August 11, 2014 Pics tomorrow Quote Link to comment
RTB Posted August 11, 2014 Report Share Posted August 11, 2014 Nice build. Did you think about trying to get longer rods? I know in my frankenmotor (l20, Z22, 6 inch rods) I could get the z20e rods to work which give a better rod/stroke ratio. I remember when I was talking to Troy and Dave Rebello about my build before I found pistons to work with my 6 inch rods they advised against me using a z22 with l20 rods. just food for thought. Quote Link to comment
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