edhunter Posted November 25, 2007 Share Posted November 25, 2007 First let me say I've read every thread I could find on here about head/block combo's... But I've found conflicting info, so looking for a bit of advice. I bought a 260z ITS car a few months ago. E88 head, but I don't know much about it. Car will be a track car only - no W2W racing so no class-specific rules, just HPDE, maybe TT after I get used to it. I've not driven this car at all, but the engine seems to run well, with good oil pressure, no funky noises, etc... Plugs are pretty nasty, but I've read the flat top carbs were set to run rich on these ITS cars.... Static compression cold, with plugs in, didn't open the throttle blades of around 185 across all 6. Engine has been pulled, the cam is stamped with a *C* on the tail end. Engine needs to be cleaned up a bit, as the oil pan, oil pump, valve cover, etc all have oil leaks. Car has not been raced in 7 years, but seller said it had a recent overhaul not long before then. The pistons are +.040 if I remember correctly. I plan to upgrade the brakes and the front LCA/TC rods. It's got illumina coilovers front and rear. 4 speed, 3:70 LSD out of a Subaru. The car is gutted, in the process of strengthening the cage some. Now gotta decide what to do with the engine if anything. I have this engine, 2 old 240 engines w/ E31 heads as well. I've already traded the flat top carbs for a set of 72 dome carbs, will keep the E36 intake... Option 1: Keep what I've got, just clean it up a bit and run the dog snot out of it.... Option 2: Buy a turbo F54 block, put the E88 head complete on it and run the dog snot out of it... Option 3: Buy a F54 flat top block, put the E31 on it - high compression but this will be a track only car so I can spring for the $$ fuel.. BTW, in the latest issue (Nov07) of Grassroots Motorsports, this is what they recommend.. to quote "John Williams recommends starting with a 2.8L block from a 81 or 82 Datsun 280zx for a nice bump in displacement... Top the block with a free-flowing E-31 head treated to a light shave, and the comp ratio will be around 10.5:1 or 11:1. (While the later 280Z and ZX heads have larger valves, the E-31 still flows best)..... With a header and tuning this engine should yield around 180Hp to the wheels.." So they're recommending a basic E31 w/o enlarging the valves here?? Good idea or not? Option 4: Buy a flat-top F54, then a P90 head, mill it down 0.080, swap the valves for the taller ones from a N47, and shim the towers 0.080. I'd guess this would be the most $$ option of the 3... any guesses what this would cost?? +/- cam swap?? Also, if I do option 3, can I transfer the cam from the 260 to the 240 engine (one of the 240z the valve cover got busted, the cam/valvetrain looks pretty nasty), would it be worthwhile?, or should I spring for a new higher lift camshaft (any recommendations here?)... Just trying to decide what to do with what I've got... ed hunter Quote Link to comment Share on other sites More sharing options...
JSM Posted November 25, 2007 Share Posted November 25, 2007 If money is not an option go w/ 3. If it is stay w/ option 1. You've switched the carbs which is a good thing. 260 cam should work fine in the 240 head. I think it is smite more agresssive than the stock E31. There is so much debate on heads. Do what u feel is best on the info you've read. Good luck and post some pics on the Projects forum. Quote Link to comment Share on other sites More sharing options...
ihatejoefitz Posted November 25, 2007 Share Posted November 25, 2007 I would research to find out which version of the E88 you've got there, most likely it's the "better used as a boat anchor" stock version. Don't know why you'd want the dished piston block in option 2... If your head isn't the version without quench I would go with option 1. If it is, I would go with option three w/ larger valves. -http://www.geocities.com/zgarage2001/z.html Quote Link to comment Share on other sites More sharing options...
edhunter Posted November 26, 2007 Author Share Posted November 26, 2007 Don't know why you'd want the dished piston block in option 2... http://www.geocities.com/zgarage2001/z.html Re: option 2 - I read somewhere on here where using the non-quench heads like the later E88 (which I think is on my 74), or the N42/N47's work pretty well with the dished pistons - something about if you put them on a flat top they ping like crazy, but do well on the dished ones.. Profess to know little about these engines (I'm really a Ford guy), but trying to learn as I go... Option 3 would be better than option 4?? Sortof surprised at that one... I thought the F54/shaved P90 was the favorite now... Thanks for the tips guys, I appreciate it! What should I have to spend to get the E31 block refreshed with larger valves, valves unshrouded? ed Quote Link to comment Share on other sites More sharing options...
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