S30Turbo Posted October 30, 2012 Share Posted October 30, 2012 What is the best block for a L31et, A f54 block or a n42? Link to comment Share on other sites More sharing options...
luseboy Posted October 30, 2012 Share Posted October 30, 2012 Referring to the fact that Nissan used the F54 block to make the factory L28et, and that it's widely considered the "best block" I'd go out on a very sturdy limb to say that the F54 block would be your "best choice." As far as I know, they really aren't much different except the F54 has the siamesed cylinders, adding strength. Also they are the latest block so I guess you gain maybe a bit better metallurgy, and a newer block. Refer to this: http://datsunzgarage.com/engine/index.htm Link to comment Share on other sites More sharing options...
PMC raceengines Posted October 30, 2012 Share Posted October 30, 2012 (edited) before giving advice make shore you have a idear about the subject ,,,, Some f54s are so thin in the bore you are lucky to get to 88mm ,1 in 3 do not have any wall in them and sonic fail , its the N42 that will take a big bore most pass the sonic test but most times i have to move the bore to get wall thicknes to get 89mm because there the block that is Siamesed you can do that .... f54 is a better block for cooling because water flows around the hole cylinder and this was a better thing in the turbo engine , but in big stroker engines with big bores the N42 is the block to have Edited October 30, 2012 by PMC raceengines Link to comment Share on other sites More sharing options...
rossman Posted October 30, 2012 Share Posted October 30, 2012 (edited) before giving advice make shore you have a idear about the subject ,,,, Some f54s are so thin in the bore you are lucky to get to 88mm ,1 in 3 do not have any wall in them and sonic fail , its the N42 that will take a big bore most pass the sonic test but most times i have to move the bore to get wall thicknes to get 89mm because there the block that is Siamesed you can do that .... f54 is a better block for cooling because water flows around the hole cylinder and this was a better thing in the turbo engine , but in big stroker engines with big bores the N42 is the block to have Yep, I got a similar story from Rebello when I questioned his decision to use an N42 over F54 for my 89mm bore bottom end. Edited October 30, 2012 by rossman Link to comment Share on other sites More sharing options...
PMC raceengines Posted October 30, 2012 Share Posted October 30, 2012 In our strokers i go throu 5 blocks to get 1 that will go to 89mm , its getting hard now to go to 89mm , iv only had about 3 f54s that have made it and it was only just , i have seen some 90mm N42 blocks Link to comment Share on other sites More sharing options...
S30Turbo Posted October 30, 2012 Author Share Posted October 30, 2012 I currently have the f54 in a stock l28et in my car but I do have a spare n42 block. And I had an idea of making it a L31et. Link to comment Share on other sites More sharing options...
johnc Posted October 30, 2012 Share Posted October 30, 2012 There is no best! When will you folks figure that out. We even made a rule! Link to comment Share on other sites More sharing options...
ctc Posted October 30, 2012 Share Posted October 30, 2012 (edited) Don't do the stroker. I started that way and now have the turbo. Money better spent upgrading the turbo. Edited October 30, 2012 by ctc Link to comment Share on other sites More sharing options...
Z Greek Posted October 30, 2012 Share Posted October 30, 2012 I currently have the f54 in a stock l28et in my car but I do have a spare n42 block. And I had an idea of making it a L31et. Link to comment Share on other sites More sharing options...
Z Greek Posted October 30, 2012 Share Posted October 30, 2012 I have bought several N42's at our local pull and save yard for $150 for complete engine. Around 6-8 Z's seem to filter through each year. There is one out there right now, I just don't feel like crawling around in the rain to pull it, and it will be snow soon! Link to comment Share on other sites More sharing options...
ctc Posted October 30, 2012 Share Posted October 30, 2012 (edited) I have bought several N42's at our local pull and save yard for $150 for complete engine. Around 6-8 Z's seem to filter through each year. There is one out there right now, I just don't feel like crawling around in the rain to pull it, and it will be snow soon! Try to find those engines in SoCal. I agree they are out there but not at that price. Or you have to wait around awhile to find one. At least we don't have snow. Francisco, Don't get me wrong I like strokers, I spent close to $7,000 on my stroker and am now on a turbo motor. If I had the $7,000 straight up for improvements on the turbo L28, I would be a lot farther ahead. Get an aftermarket ECU sorted out on the L28ET, before you look for more displacement. Small steps and keep the car drivable, you will enjoy it more. Edited October 30, 2012 by ctc Link to comment Share on other sites More sharing options...
johnc Posted October 30, 2012 Share Posted October 30, 2012 Yep, I got a similar story from Rebello when I questioned his decision to use an N42 over F54 for my 89mm bore bottom end. Same for me from Sunbelt when I had them build a 3L. So, in this thread, we have three professional engine builders chose the N42 over the F54. Link to comment Share on other sites More sharing options...
HowlerMonkey Posted October 30, 2012 Share Posted October 30, 2012 How big is a stock bore L28 with the ld28 crank? Link to comment Share on other sites More sharing options...
ctc Posted October 30, 2012 Share Posted October 30, 2012 How big is a stock bore L28 with the ld28 crank? 2.893 litres with the Ozdat calculator. Link to comment Share on other sites More sharing options...
S30Turbo Posted October 30, 2012 Author Share Posted October 30, 2012 Yes I will keep my L28et and upgrade it to MS and Upgrade other things before going for more displacement. Link to comment Share on other sites More sharing options...
S30Turbo Posted October 30, 2012 Author Share Posted October 30, 2012 Will an L28et with the same upgrades and boost make the same power as an L31et with the same upgrades and boost. Is there pros and cons for building an L31et (besides the money) and it looks like Engine builders prefer the N42 block. Link to comment Share on other sites More sharing options...
Hybrid240z Posted October 30, 2012 Share Posted October 30, 2012 I bought a used L31ET with an F54 block. They sonic tested five F54 blocks until they finally found one that they were happy with. Crossing Fingers...haven't ran it yet but has even compression. It sounds like it would be a good idea to have any block that you are planning to use sonic tested. Link to comment Share on other sites More sharing options...
S30Turbo Posted October 30, 2012 Author Share Posted October 30, 2012 Hybrid240z - I would like to hear and see a Dyno on that l31et. Do you use the 240z rods or the l28et rods. I know for a stroker builders use the ld28 crank and 240z rods with 240sx pistons. Link to comment Share on other sites More sharing options...
johnc Posted October 30, 2012 Share Posted October 30, 2012 OK, this thread is about done. You're asking questions that can be easily found via searching. Take a few days and find these easy answers please. Link to comment Share on other sites More sharing options...
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