Ben Posted February 17, 2004 Share Posted February 17, 2004 A set of custom slugs would be my answer Quote Link to comment Share on other sites More sharing options...
greenmonster80 Posted February 19, 2004 Share Posted February 19, 2004 A large problem with 3.1 builds is someone is always looking for a way to build the thing cheaper and using junkyard parts. I can not agree more with the before mentioning of balancing. Balance the entire assembly. From the front pulley all the way tru to the flywheel. Since all the pieces are out anyway, it makes too m,uch sense. After lots of looking around and reading forums I decided to build mine the way it has been done in Japan for years. Why go this route? Well if they have strokers that run with big carbs and blow-thru turbo charging on drag cars that pull double duty as daily drivers than they have some how solved the reliability factor. Builders recommend either the F54 or N42 block. This debate could go forever. Just pick one already. Ld crank is a must. Take everything you know about different rod/piston combinations and forget it. Manufactures such as HKS, Tomei,Kameari and others have been making special pistons with redesigned ring specs to fit various rods lenghts. Get this they even tell you which set of connecting rods to use. They also tell you what the displacement will be using the LD crank and what piston set you purchase. For example my LD crank, 89mm tomei pistons and L20 (inline 6) connecting rods clears the 3.1 liter build safely and will hold thru future plans of turbo. Morale of the story is if you are going to do it, do it correctly don't wing it with junkyard parts trying to wing it. Quote Link to comment Share on other sites More sharing options...
greenmonster80 Posted February 19, 2004 Share Posted February 19, 2004 A large problem with 3.1 builds is someone is always looking for a way to build the thing cheaper and using junkyard parts. I can not agree more with the before mentioning of balancing. Balance the entire assembly. From the front pulley all the way tru to the flywheel. Since all the pieces are out anyway, it makes too m,uch sense. After lots of looking around and reading forums I decided to build mine the way it has been done in Japan for years. Why go this route? Well if they have strokers that run with big carbs and blow-thru turbo charging on drag cars that pull double duty as daily drivers than they have some how solved the reliability factor. Builders recommend either the F54 or N42 block. This debate could go forever. Just pick one already. Ld crank is a must. Take everything you know about different rod/piston combinations and forget it. Manufactures such as HKS, Tomei,Kameari and others have been making special pistons with redesigned ring specs to fit various rods lenghts. Get this they even tell you which set of connecting rods to use. They also tell you what the displacement will be using the LD crank and what piston set you purchase. For example my LD crank, 89mm tomei pistons and L20 (inline 6) connecting rods clears the 3.1 liter build safely and will hold thru future plans of turbo. Morale of the story is if you are going to do it, do it correctly don't wing it with junkyard parts trying to wing it. Quote Link to comment Share on other sites More sharing options...
Ben Posted February 19, 2004 Share Posted February 19, 2004 Do you have any catalogue data, or web pages that detail these specific components (HKS etc)? In my experience, these manufacturers move very fast to devlop new components for the latest engines. Then unfortunately the older stuff, although still available, isn't shown in the current product lineup. Quote Link to comment Share on other sites More sharing options...
greenmonster80 Posted February 20, 2004 Share Posted February 20, 2004 Simply call these manufactures, you will be surprised to find out what they still have on the shelves at different wharehouses. Be patient and keep working it. Quote Link to comment Share on other sites More sharing options...
Mack Posted February 20, 2004 Share Posted February 20, 2004 thats great buying parts from overseas companies and all, if you have the money and a hookup over in the land of the rising sun. But how much is your motor going cost you in the end? I am stuck with junkyard parts, ever seen anyone build a stroker out of an LD28 block? I know I dont have the cash for forged rods and forged pistons. know why they use those custom pistons with custom ring packs? because the rod/stroke ratio on an L31 stroker motor SUCKS, thats why. Also, the correct "old school" way to build a 3.1L stroker was to use Honda XR500 motorcycle pistons and FJ20ET 140mm connectiing rods, which are as close to indestructable as you can get. FJ20ET rods and L20A rods are close in height only. also, "junkyard parts" can be balanced like any other parts. Junkyard parts are sometimes preferable to brand new shiny parts. The BMW F1 team in the early 80's used to scour junkyards for blocks for their motors because they had already been heat cycled and were stronger than a brand new block. McAdam Quote Link to comment Share on other sites More sharing options...
SHANE Posted February 21, 2004 Share Posted February 21, 2004 Well i have not seen one pro to building a stroker. All that extra work and they just are not making any more power than what a bone stock block can handle. I put down 436 FT LB of torque to the wheels completely UNTUNED. Stock head, stock block, stock intake manifold, stock exhaust manifold. That was pushing 18psi. Now granted i am smart enough to through that Nissan headgasket in the trash and use a Felpro, but other than that we are talking stock. This motor has 145,000 miles on it too. That was a few years back, now i run 25psi completely untuned. Nothing more than seat of the pants tuning with the SDS. My solution for tuning? Nitrous!!! Now i run 25 psi (big hybrid turbo) and a 75hp shot of nitrous. All on a bone stock motor. Now tell me, if a stock motor can handle all this abuse. Why in the HELL would you change it????? Oh and guess what, i have yet to have a dampner problem since i shift at 6500 rpm Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted February 21, 2004 Share Posted February 21, 2004 I hear Shane on this too. The L28ET is an unbelieveable engine. I'm running 16psi at a mile altitude and put down 419ftlb of torque, rock stock motor and Felpro headgasket. And 27mpg cruising on the highway. Quote Link to comment Share on other sites More sharing options...
jeffp Posted February 21, 2004 Share Posted February 21, 2004 First off some of you guys are putting down very respectable numbers with your setups. I built the stroker really for one reason, I HATED the doggy bottom end under non boost conditions. I thought the really sucked off the line, it drove me nuts. That was my reason for a stroker. I dont believe the 89mm pistons are a good idea with a turbo engine, the 88mm pistons would be the biggest I would ever recommend for a turbo application, for the reasons stated above. I also increased the static compression to 8.5:1 for better power off boost and so I could fudge on the turbo somewhat. The one thing I have noted on my engine and setup was when I could build boost. My second turbo would build bost @ 3K not a ramp up, but instantly when you mashed the gas pedal 20psi of boost, the car was almost uncontrolable. This new turbo, although it spools slower( at least with no tuning, and it needs tuning bad) but the transition is much smoother and I can control the car much better now. The rod stroke ratio in my opinion was not sufficient with the 240 rods,at least for longevity, so I had custom length rods made for the engine. so that was my reasoning, and it has turned out well for me. My last dyno turned out 471 foot pounds of torque, and the turbo was out of air, so I went bigger. We will see what happens with the new program, 72Lb injectors and a turbo that can push 35psi at a much higher flow rate then my last unit. Quote Link to comment Share on other sites More sharing options...
510six Posted February 21, 2004 Share Posted February 21, 2004 I have had two 3.0 stroker motors.The current one makes 535 rwh and 492fpt, my NA motor made 256rwh and 270fpt on N20.What I have learned is that if your going to build a 3liter have it statically and dynamically balanced and run a comp dampner.I learned that lesson after my flywheel came loose and $400 later I had a NISMO comp damper with a custom pully as I drove the car on the street.I am currently running a ATI dampner and can run it on the street only due to the fact that I run an electric water pump .3" crank pully and 2" pully on the alternator.I love the torque,but a friend of mine has a bone stock 280zxt motor in a 240z with a t3-t4 a front mount and 18psi boost and IT haul *ss.The 3 liter in NA form and turbo on N20 was-is awesome.The first motor was a junkyard parts congloberation, VG30(87mm) pistons L24 rods, Diesel crank.The second custom JE VG 30(87mm) pistons Cunninham rods and Diesel crank, both motors were raced preped and balanced.The first survived 80 10 lb bottles of N20 and is in my friends 240z now. The second has run numerous drag passes and runs low11`s high 10`s. Quote Link to comment Share on other sites More sharing options...
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