pjo046 Posted March 1, 2006 Share Posted March 1, 2006 First of all, when I tore apart the engine about a year ago I didn't know much about the internals of these engines or engines in general. I hadn't bought the How to rebuild and How to modify books yet at the time either. So I made one big mistake when trying to remove the rear main cap. Instead of using two bolts loosely inserted into the cap as handles to get it of, I lightly and repeatedly hit the end of the crankshaft with a rubber hammer and used my hands to try and rock the main cap back and forth untill I could get it loose. Is it likely that I can have damaged the crankshaft because of this, by having induced some runout/bend? If so, I guess a new crankshaft would be needed? In the how to modify book it is recommended to remove the main oil gallery plugs, and drill and tap the holes instead. Is this something most of you do when rebuilding a shortblock? Is it recommended? Also, it is advised to enlargen the upper bolt on the slack side chain guide, because these can break of because of chain slap. Will this be a problem when the engine isn't run above 7000RPM? Or would you recommend me doing this upgrade as well? The engine I am rebuilding, I bought from of a used-engine dealer in the USA, through Ebay. The engine only had 50K miles on it(Was taken from a totaled 280ZXT and had been in their storage for several years), and I believe that mileage to be true due to the condition of the inside of the engine. None of the main or rod bearings show any signs of wear, and the cam-chain, tensioner and guides all looked like new. However, because the engine has been stored away for a long time, a lot of rust has accumulated in the cooling passages. I found that out just yesterday when removing the freeze plugs. Is it normal with some rust behind those, or is this a very bad thing? The books don't say much about it. Will hot tanking clean up things like that? So, here is what I have planned for the shortblock, along with some more questions: - I will polish and balance the rods and fit them with ARP rod bolts. Will shot peening be necessary for a 400rwhp build? - I will balance the pistons - I will check the crankshaft for runout, taper and out of round, and if that is all within spec I had only planned on polishing the crank journals and don't do anything else to the crankshaft. Is there something else I should do to it? I have by the way bought a crank scraper which I will install. - The block I will have honed to remove the glaze for proper ring seating, I am in the process of smoothing out the block interior to remove casting lines and casting sand residues, it will be resurfaced and hot tanked, and then there is the question wether or not to remove the main gallery plugs and tap the the holes, and wether or not to resize the upper bolt on the slack side chain guide. Is there something I am forgetting that I should do to the block? The head is rebuilt by lonewolf performance, so the only thing I should need to do with it is install it and adjust the valve clearances. Furthermore, I have Clevite 77 main and rod bearings, and ARP head and main studs. All in all, is there something I have forgotten in this build, or will this be enough to make a more or less bulletproof engine for my goals? With an engine with such low mileage, is it recommended getting a new oil pump? I have read that many times, new pumps are out of spec. How about the spindle gear? If I manage to properly balance the rods and pistons myself, will it matter much that the crankshaft hasn't been balanced in the "overall" balance of the bottom end? If you get what I mean? Because balacing the crankshaft is of course something I can't do myself, and having it done will be ridiculously expensive over here in Norway. (about 500$) Quote Link to comment Share on other sites More sharing options...
naviathan Posted March 1, 2006 Share Posted March 1, 2006 Crank shafts can be straightened by a machine shop and it should be checked anyway. Follow the How to rebuild book and you won't be disappointed. Do it right the first time otherwise that bolt COULD break and you'd end up doing it all over again or buying a new motor. Good luck with it! Quote Link to comment Share on other sites More sharing options...
TheNeedForZ Posted March 2, 2006 Share Posted March 2, 2006 To put your mind to peace, you probably didin't bend the crankshaft when you removed it. If you dropped it on the floor then it would be bent. Quote Link to comment Share on other sites More sharing options...
pjo046 Posted March 2, 2006 Author Share Posted March 2, 2006 Good to know! I will of course check it when I receive the measuring tools TonyD bought for me, but I must say I have been a bit worried. So does anyone know if hot tanking will remove the rust in the cooling passages? Unfortunately I don't have my camera here at the moment, as my girlfriend is on vacation and has taken it with her, so cant take any pictures of it. And is it recommended getting a new oil pump when the one I have only has 50K on it? Quote Link to comment Share on other sites More sharing options...
zeiss150 Posted March 2, 2006 Share Posted March 2, 2006 Hot tanking my 30+ year old 240 block seemed to get rid of all the rust it had. the rust would have to be really bad to mess with the flow of coolant. I'd be more worried about the rust messing up your radiator. 50 thousand miles is nothing on a Z oil pump .... but... I like the idea of starting fresh with everthing its worth the $80. What injectors are you using and how much did they cost you? Good luck, it sounds like its gonna be a beautiful car (also what color paint?) Quote Link to comment Share on other sites More sharing options...
pjo046 Posted March 2, 2006 Author Share Posted March 2, 2006 I have a set of Lucas 550cc injectors. Got them of ebay for about 300$ I believe. New of course. As for the paint, it will be BMW steel grey (400 stahlgrau). Also it will have the original chrome fenders front and rear, original chrome sideview mirror on the driverside and no mirror on the passenger side. I will run a MSA airdam up front, with brake cooling ducts. The rims I will be using are 17x7 Konig Imagine, paired with 225/45-17 tires. Haven't decided yet wether or not I will shave the drip rails. I have shaved the side marker lights front and back, and also shaved the fuel-door.(Will use a summit fuel cell). I am removing all the Z emblems etc, just keeping the rear hatch grilles that are original on the first generation 240Z's. So I hope it will be a clean and good looking car. Quote Link to comment Share on other sites More sharing options...
zeiss150 Posted March 2, 2006 Share Posted March 2, 2006 are thoes injectors "plug and play" or did you have to modify your intake? Sounds like it will be a beautiful car. I can't wait to finnish mine. Quote Link to comment Share on other sites More sharing options...
pjo046 Posted March 2, 2006 Author Share Posted March 2, 2006 When I bought them, I was intending to use the stock datsun manifold. They would be plug and play into the manifold, but they are O-ring injectors, so some modifications would perhaps be required for them to fit a barbed fuel rail. But along the way I decided to buy a custom turbo manifold from Lonewolf Performance, so the intake and fuel rail have been made to fit these injectors specifically. Yes, I hope it will look good. I don't know how much time I have spent wondering about how I want the car to look. Thought I had decided upon something, then I saw something else that I liked. It's hard! After seeing 240hoke's car all done, I was wondering about going for that color for a while. But I think it will be the BMW steelgrey, haven't seen another Z with that color yet. How far along are you with your car? What are the specs on it? Quote Link to comment Share on other sites More sharing options...
zeiss150 Posted March 2, 2006 Share Posted March 2, 2006 Im about 60% done with my car. I have a 72 240 I've compleatly re-done the interior, as well as rebuild the engine. I upgraded to an L28 F54 short block with ballanced rotating mass and 20 thou. over bore and flat top pistons. It has an N42 head with headers and Im running SU's right now. Its a realy fun car to drive I would guess that I have about 180 RWHP. the rest of the work that needs to be done is body work. I'm doing everything myself so its taking me a long time. I plan on converting my engine to turbo, so im slowly gathering all the parts nessary. I bought a Z31 water cooled t3 turbo and rebuilt it so thats ready to go. I have an N42 intake manifold that I will be Cleaning up and putting between 420 and 550 injectors into. I also have a 60mm TB. So I just need a P90 head, CAS distributor, Map sensor, IC, and megasquirt engine management, and I hope to get somewhere in the ballpark of 300 RWHP. The body work is the hardest part. Once Im done with that I'll paint it 350Z red (paint code A06). It might take me another year or longer to get the paint on:(. I'll probably do the turbo before I finnish the paint. Right now its a great sleeper car. I smoked an Infinity G35 last week with my whimpy 180 HP so I can't wait to see what she'll do with 15lbs of boost. Quote Link to comment Share on other sites More sharing options...
pjo046 Posted March 2, 2006 Author Share Posted March 2, 2006 Sounds like a good plan! So if you have flat tops and a P90 you'll get somewhere around 8.5:1 CR depending on which HG you use. That's about where I am as well. For 300RWHP, 420cc injectors would be more then enough. But of course, it's always smart to plan ahead, in case you later on feel that you need more power. A watercooled turbo is a good choice to prolong the turbochargers life. Does Z31 T3 have the same A/R etc as the 280ZXT T3? I have been gathering parts for my car since december 2004 when I bought it. I have most of the parts for the puzzle now. Can't wait to put it all together. Yea, can't say I'm looking forward for the bodywork on the car myself. The underside's ok, because nobody will see it anyways so it doesn't have to have a perfect finish. I was planning on having the car painted by an automotive painter, but because of the high costs involved I'll just do it myself. It will be my first time, but hopefully I'll manage it. The prep work is what is important. Quote Link to comment Share on other sites More sharing options...
zeiss150 Posted March 3, 2006 Share Posted March 3, 2006 As far as I know the Z31 t3 is exactly the same as the 280zx t3 the only differance is the water cooled bearing section. My block has a 20 thousands over bore so my CR should be 8.6:1 with the P90. I figure if I start with 550 injectors then I'll have a lot of room to grow with a bigger turbo/ throttel body(70mm) in the future. So far this is all theory for me ... I only have experiance with N/A L28s so going turbo will be a huge learning experiance for me. You should be able to paint your car yourself and get a professional qauality job out of it. I painted a vespa scotter that turned out awesome and it wasn't that hard. And you're right, the quaility is all in the prep work. good luck and keep us posted Quote Link to comment Share on other sites More sharing options...
Gdemirchy Posted November 16, 2006 Share Posted November 16, 2006 gfdt When I bought them, I was intending to use the stock datsun manifold. They would be plug and play into the manifold, but they are O-ring injectors, so some modifications would perhaps be required for them to fit a barbed fuel rail. But along the way I decided to buy a custom turbo manifold from Lonewolf Performance, so the intake and fuel rail have been made to fit these injectors specifically. Yes, I hope it will look good. I don't know how much time I have spent wondering about how I want the car to look. Thought I had decided upon something, then I saw something else that I liked. It's hard! After seeing 240hoke's car all done, I was wondering about going for that color for a while. But I think it will be the BMW steelgrey, haven't seen another Z with that color yet. How far along are you with your car? What are the specs on it? Quote Link to comment Share on other sites More sharing options...
Gdemirchy Posted November 16, 2006 Share Posted November 16, 2006 t Quote Link to comment Share on other sites More sharing options...
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