David K Posted November 7, 2002 Share Posted November 7, 2002 ok ive aquired some parts. im grinding an e88 head for fuel injectors. simple work. combo: e88 f/i head 2.4 rods 2.8 dished pistons 2.8 block 2.8 turbochager 2.8 crank can somebody tell me what kind of compression i would be running without the turbo? also, with the turbo, how much compression would that be? Quote Link to comment Share on other sites More sharing options...
David K Posted November 7, 2002 Author Share Posted November 7, 2002 jeeezus i just did a calculation on a program and it came up as 11:17:1 w/out turbo WOW. Quote Link to comment Share on other sites More sharing options...
tec280zx Posted November 7, 2002 Share Posted November 7, 2002 I wouldn't consider turbo with this setup. Way too much compression. You're looking at 10.6 - 11.0:1 depending on the head gasket you use. Brandon 81zx Quote Link to comment Share on other sites More sharing options...
DavD3 Posted November 7, 2002 Share Posted November 7, 2002 I will try to answer on your question,in case i'm wrong others will correct me.Turbocharger has nothing to do with CR of your engine.With turbo you can't run high CR and this how it should be.(well at least in L series nissan engine).Most of people run from 7.8 to 8.3 CR with turbo, and i think 7.9-8.1 is the ratio to have when we are talking about abome mention set up.With N/A in daily driven car you should be fine with CR below 10.0.Pinging is the problem for high CR engines which run on low octane gas. Ok,next is your combo,L24 rods are not a good idea, because 2.8 dished pistons from L28 will have clearance problem ( deck height of 2.73 ) You have to remeber that CR depends on head gasket thickness, and depending if you are using Felpro or HKS 1mm or 2mm you will alter CR. If you want to build a stroker then you have to change something in your combo,because in a way you have now i don't think it will work out.Sorry. Quote Link to comment Share on other sites More sharing options...
David K Posted November 7, 2002 Author Share Posted November 7, 2002 ok how about this. it came out to 12:54:1 2.4 pistons 2.4 block 2.4 rods e88 head felpro gasket l28 crank will i have clearance problems using the 2.8 crank? Quote Link to comment Share on other sites More sharing options...
DavD3 Posted November 7, 2002 Share Posted November 7, 2002 Yes you will have problems with such combo too.If you want to have a stroker without diesel crank,here is your combo: L28 F54 block L24 9mm rods L28 crank KA24 pistons E31/88 head 1mm HKS head gasket this give you engine of 2949cc andCR of 9.56:1 with E31 and 9.23:1 with E88. This is with flat top KA24 pistons if you have dished ones CR will drop to 7.79:1 and 7.58:1 respectively.Keep in mind that this combo requires overbore of block on 3mm, and block must be sonic tested before going to build this engine. Quote Link to comment Share on other sites More sharing options...
David K Posted November 7, 2002 Author Share Posted November 7, 2002 can somebody please explain deck height to me. should i have a - deck height? Quote Link to comment Share on other sites More sharing options...
DavD3 Posted November 7, 2002 Share Posted November 7, 2002 + deck height- piston at the top center protrudes from the block( comes out into combustion chamber of the head) - deck height -piston at the top center doesn't hit the top of the block ( stays inside of the cylinder/block ) Not the best expalnation but i hope you got an idea. Quote Link to comment Share on other sites More sharing options...
David K Posted November 7, 2002 Author Share Posted November 7, 2002 + will hit the head and - will clear it making your combo usable? correct? Quote Link to comment Share on other sites More sharing options...
DavD3 Posted November 7, 2002 Share Posted November 7, 2002 Not 100%,If you look into engine programm L28 has +0.030 deck height, so it's normal.Above it,honestly i don't know and don't wanna know.negative deck height also depends on the numbers.For me, i thought if Nismo sells 2mm head gasket and this gasket was used on L28 engine then total off 2mm distance between piston at the top center and head is ok.In combo which i mention there is -1.37 deck height and 1mm head gasket which gives you 2.37mm distance.I think it will work out just fine,again this is my opinion. Quote Link to comment Share on other sites More sharing options...
Bob_H Posted November 7, 2002 Share Posted November 7, 2002 David, Care to enlighten us as to why you want to run an E-88 with a turbo? Just sounds like you are asking for problems. If you don't want the P-90, I say go with the N-42. Your compression will still be rather high, but closer to what you want. How about telling us what CR you are shooting for. -Bob Quote Link to comment Share on other sites More sharing options...
DAW Posted November 7, 2002 Share Posted November 7, 2002 The combination you've described doesn't work. The pistons are sticking up out of the block 2.6mm due to the L24 rods (133mm) used with L28 crank and pistons. L28 rod length is 130.4mm. I don't understand the high compression ratios you are talking about. L28 dished pistons have 10.9cc dish. There are 4 E88 heads. If you use the rare early one (like E31) you boost c.r. modestly above stock N42 c.r. of 8.3:1, maybe to 8.9:1. The most common E88 gives the same c.r. as the N42 head on the N42 shortblock, 8.3:1. If you use the E88 from the L26 it will drop your c.r. probably just below 8.0:1. As you can see, the particular E88 you are using does make a difference in c.r. but none of these combos result in c.r.s that are incompatible with turbocharging. So why not just use an N42 head? it has the proper valve sizes and injector notches already there. DAW Quote Link to comment Share on other sites More sharing options...
yo2001 Posted November 7, 2002 Share Posted November 7, 2002 O, E88 doesn't have EFI provision David. I had to get mine welded and drilled/tapped. 133mm rods can work with custom pistons. hint hint 38.?MM is stock wrist pin height so you need to raise the wrist pin height and run 35.?mm (I can't remember the tenth) I'm going with 30mm wrist pin pistons and 136-137mm custom rods (I haven't figure out the exact # yet) That should give me 1.7+ stroke/rod ratio. O do you still want the intake? I don't have a camera so I couldn't take pic. (Well, I had one but it was el cheapo and no loner in service)email me if you want it or I'll see you on AIM Quote Link to comment Share on other sites More sharing options...
Mudge Posted November 7, 2002 Share Posted November 7, 2002 Originally posted by David Karey:+ will hit the head and - will clear it making your combo usable? correct? Come into the combustion chamber, not neccessarily hit anything, if it hit anything it would likely be valves from a high lift/duration cam, which is part of the math that you likewise should perform if adding a biggy cam, thats where valve reliefs come in. Quote Link to comment Share on other sites More sharing options...
David K Posted November 8, 2002 Author Share Posted November 8, 2002 Originally posted by yo2001:O do you still want the intake? I don't have a camera so I couldn't take pic. (Well, I had one but it was el cheapo and no loner in service)email me if you want it or I'll see you on AIM do you have paypal? Quote Link to comment Share on other sites More sharing options...
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