righteousrags88 Posted December 8, 2015 Share Posted December 8, 2015 So Im working on my 72 240z. I got a 78 280z that I purchased for the engine and tranny that I was gonna swap over to the 72. The engine has been built by the PO and I have the build sheet with copies of the receipts. Basically he temporarily put the stock cam back into it but I wanted to run a more aggressive cam as the engine comp is 10.5. Also its FI but I have a set of triple 40dcoe webers that I wanted to convert it to. Im looking for someone around the Seattle area who knows these L series engines and with the parts combo that I have and want to put into it can put it all together and tune it for most optimal performance. Im not at the stage of where Im ready to put it into my 72 as its getting painted right now so Id want to use this time to button together and tune the engine so that when the time comes I can just drop it in. Feel free to message me and I can give my phone number and message you my build sheet. Thanks Igor Quote Link to comment Share on other sites More sharing options...
seattlejester Posted December 8, 2015 Share Posted December 8, 2015 Unless it is a secret I'm not sure why you need to hide your build sheet. Post it up and open it to all the experienced guys on the forum. Quote Link to comment Share on other sites More sharing options...
righteousrags88 Posted December 8, 2015 Author Share Posted December 8, 2015 Sorry I wasn't trying to keep it a secret but here it is. Its a direct copy and past of what he sent me on the build. If you have questions Ill try to answer them best but Im no engine builder hence why Im asking for help. Again if you want copies of the receipts I can message you those. So to begin: The engine is a combonatin of n42 block (contains more nickel) and a p90 turbo head that I had shaved .080" to raise compresison; this head style (with peanut shaped combustion chambers, allow for ping resistance: only run 91 or up). The cam towers were shimmed up this ammount as well. The valves were redone by Rebllo (three angles). The head was ported in the exhaust bowls to allow for better flow. The head was straightened. The cam was originally stage 1 but I replaced with stock hoping to source another stock cam for a regrind for a stage 2. The valve springs are Schneider performance springs from MSA, the lash pads are hardened steel pads from JDM customs, the valve colets are from Z Car Source of Arizona. The timing kit is from ITM and the rockers are factory. Fel Pro gaskets were used. Valve seals were also fel pro. The n42 block was bored over .020" over I believe, and hot tanked. The crank was polished and the rods were balanced within a thousandth. New bearings were used all around. Pistons are cast ITM pistons (part#15401711, 280ZX .020 (.50mm) Oversize) with new rings and wrists pins. Fel pro gaskets were used. It was painted using por-15 rsut preventaive engine enamel. New freeze plugs were installed. The block was decked flat. Valve cover media blasted and powder coated. MSA cold air intake used. OEM water pump used. New puley belts New alternator New Starter. New dowle pins used for head and block Oil seal rings new (crank) Start up Lube used with ZDDP additive. Oil pan was media blasted and painted black. New plug used. The entire engine has a completley new bolt and hardware set grade 10 used, with the excpetion of a couple of specialty bolts. The spark plugs are from Nissan. the intake was media blasted and powder coated. the fuel rail was custom made. the gas tank was removed, acid dipped, lined and repainted by a radiator shop. A factory nissan fuel pump was ordered. Fuel regulator is adjustable and is from Aeromotive, with gauge on the unit. Braided steel fuel line. Stock harmonic balancer. 240sx tranny, custom driveshaft mace to accomodate the extra 2inch length, and a custom mount for the tranny made. stage 3 clutch, lighter flywheel with Nissan Japan flywheel bolts, new slave cylinder and master scylinder. New brake cyclinder, stock brake booster (2+2 booster is better, so if you switch the car out take the booster cuz its bigger) radiator is tri core with efans that are wired to an automatic temperature sensor. Quote Link to comment Share on other sites More sharing options...
seattlejester Posted December 8, 2015 Share Posted December 8, 2015 Sounds like a typical hop up on the L engine. http://datsunzgarage.com/p90/ The rest seems like a pretty good rebuild. I would fill it up with oil and crank it now to see if it builds some oil pressure and also see if it leaks, doing a rear main seal or worse the crank seal strips after it is in the car is going to be a real real bummer. I would also be tempted to take the oil pan off to check for excess silicone or debris. Has it been run before? He mentions the start up lube, has it been started and flushed? So what is the main question here? Which cam to run? How to install the triple webber? Delta cams I think is in Tacoma, when I had my head rebuilt, the builder recommended I hop over to delta and have them grind the cam if I was going for more high end, that would to me suggest they have quite a bit of experience with our cams if they could do it on the spot. Triple webber install should be as easy as pulling off the intake manifold and installing the adapter manifold, the carbs, and the linkages (make sure the stock datsun linkage is in good working order, they have a tendency to bind with age and there are well documented checks and fixes). The question will be setting up the carbs to run correctly. You could probably find some base values and order a set of jets and what not, and installing an O2 sensor would really help dial it in. I have a synchrometer that should work when it comes to that point as well, but I know that Fairlady Z motorsports has experience setting up carbs on the Z cars, but I haven't heard any news from them in a while and I'm not sure if they are still around. Quote Link to comment Share on other sites More sharing options...
righteousrags88 Posted December 8, 2015 Author Share Posted December 8, 2015 Sorry I didn't make it very clear but the build has approx 1000miles on it so its not a brand new fresh rebuild persay. I still have it sitting in the 280z and can be ran and driven except for the fact that I pulled the fuel tank out to use in my 72. Its the larger capacity 280z 2+2 tank which we've already added the mount and hanger for it since its mounts alittle wide than the 240 tank but thats a whole other topic. He said he used a stage 1 cam (Im assuming its the MSA cam due to him calling it a stage 1) but said that it wiped so he temporarily put the stock cam back on until he sourced another one. Excuse me for the term but I was wanting to run something more aggressive than the "Stage 1" cam profile but this is where Id need advice. I spoke to a guy who might end up helping me on the build and he recommended me Delta also to regrind my cams so I probably will go to them once I know what profile I should do. Don't get me wrong, I know how to turn a wrench as Im assembling the entire car together myself once I get the shell finished with paint so I'd know how to install the webers. Its the whole tuning thing im clueless about, floats, jetting, etc. That and I wouldn't know how to replace a cam correctly as I never had the quality father son time to be taught ha. Car has been a giant learning curve. Im just trying to squeeze the most out of the build while keeping it streetable on pump gas. But will be driving aggressive Quote Link to comment Share on other sites More sharing options...
righteousrags88 Posted December 8, 2015 Author Share Posted December 8, 2015 I read through that link. Maybe mines a 10.1 comp not 10.5. Is there any way to figure that out? Quote Link to comment Share on other sites More sharing options...
seattlejester Posted December 9, 2015 Share Posted December 9, 2015 Ah, then it seems like you might be golden. My thought is that just make sure to do all the really crummy jobs while the driveline is out, clutch, lock-tite on the flywheel bolts and pressure plate bolts, RMS if leaking, oil pan gasket, making sure the fill and drain plugs on the transmission can be removed, etc etc. No worries, I didn't mean to downplay how much you will be wrenching, I just didn't follow the question as to what you were looking for. There is a compression calculator online, although I'm not sure if it has the shimming in place. http://atlanticz.ca/zclub/techtips/calcs/engine%20builder/index.html You would have to find out how much shaving the 0.80 affects the volume to get the exact number, other then that you could go based off of that guys numbers with your head gasket to figure it out or do backwards math to find the chamber volume to find out the compression on yours. Installing a cam is pretty easy on these cars. If I remember there was something about never removing the cam towers in one of the books because of line honing or something of that nature and potential cam binding, but they are numbered, and they go back in pretty easily with dowels to boot. Obviously yours were removed at some point and hopefully individually checked for height and trueness prior to shimming so if you wanted removal via cam towers is an option. I remember I even had my towers mis-ordered and it went back in pretty easily, I slid it out the front the first time when I was messing around with a couple stock cams, but removed the towers and just popped it off the more times I did it as removing the radiator each time was quite a chore (the towers are numbered via square blocks on the side denoting position). Advice would be to make sure the radiator is removed and the hood is off, then insert the timing gear chain holder thingy (a piece of wood or plastic to keep the tensioner under tension and prevent the chain from falling into the timing cover, pull off the cam gear after bringing everything to TDC with the cam facing up and the distributor at the number one position (make very careful note of this, it is not unheard of that a lazy builder will just alter the plug order after installing the distributor incorrectly, so just take note of where the rotor is pointing prior to removal), and then slide the cam out the front. To remove the cam gear you may need a very big wrench to hold the cam on a designated slot/square pegs or a big screw driver to jam the cam from moving. I would circulate it a bit prior to any removal so that the cam is lubricated and wants to come out nicely. If it is just a regrind the cam should definitely fit back in without problem. Another point of advice would be to make sure for the fuel that you have a high volume low pressure pump. Don't regulate the FI pump down to the 2-4 psi for the webber you will make it very unhappy. Also I would just go for some good hose if you are redoing the fuel system, that was one of my bigger regrets, I spent a lot of time and effort installing very small hose very securely, only to find that when I stepped up to FI all the lines had to be replaced. Regarding the webber carbs, I think more or less there are two camps, one is to have a tuner that can mess with it for you and sync it for you, stock all the parts and adjust it for you when the weather changes, and the other is to become really intimately knowledgeable about all the jets, valves, etc and order the full tuning kit so you can adjust it as the weather changes or if you change elevation etc. Other then that a synchrometer will help to set them so they are all breathing in the correct amount, and an AFR gauge with an O2 sensor will let you know how good the tune is. A good tachometer will help you Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted December 9, 2015 Share Posted December 9, 2015 (edited) Doug at Fairlady Z is still around. But he's changed the name of his shop to UP Garage. It won't be cheap but he's not unreasonable. Just have the car as ready as you can get it beforehand. He does have a dyno. He's in Tacoma Edited December 9, 2015 by Chris Duncan Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.