frey1691 Posted January 23, 2012 Report Share Posted January 23, 2012 ok guys well with my 85 parts truck i got a z24 motor it was having compression issues? which is why the kid said he took it out. when i got it and well still it is in pieces and not labeled well :unsure: . so my first objective because of just how broke i am is to try and save up enough money to take the head to the machine shop. the head will probably get put on the z22 that is in my 720 right now just until i can get enough parts and time to do a full rebuild however i dont know what to get done at the machine shop? i know for sure i want a bit of a port(mild-medium) and i want everything resurfaced and probably a valve job done. oh and im probably goin to run a single weber for right now and move up to side drafts later or possibly try and go with the r1 carb idea. so my question is should i do more even though im keeping the bottom end stock for right now? and after wards what would be some good ideas for building the bottom end so i can start collecting parts. i like the functionality of the l20b but in my oppinion there aint no replacement for displacement so im trying to go as big bore as possible too. also another question that im just wondering is as far as a valve job is concerned when the say 3 angle or 5 angle what are the angles they are refering to and what bennifits does having more or less angles have? Quote Link to comment
ggzilla Posted January 23, 2012 Report Share Posted January 23, 2012 Why take the head to a machine shop? What is wrong with it? Datsun specifications call for a 3-angle valve job which is factory spec. Any more doesn't make a noticeable amount of power (less then 1hp) but reduces the service life. Unless there is something wrong with the head, I would just use it. Measure the surface with a straight edge, if it has less than the 2 thousands inch warp, it is still good. Quote Link to comment
frey1691 Posted January 23, 2012 Author Report Share Posted January 23, 2012 the head is just dirty and i was hoping to get a little extra power out of it but wasnt trying to go over the top yet but everything looks ok but then again i cant say for sure Quote Link to comment
Draker Posted January 23, 2012 Report Share Posted January 23, 2012 Why take the head to a machine shop? What is wrong with it? Datsun specifications call for a 3-angle valve job which is factory spec. Any more doesn't make a noticeable amount of power (less then 1hp) but reduces the service life. Unless there is something wrong with the head, I would just use it. Measure the surface with a straight edge, if it has less than the 2 thousands inch warp, it is still good. You could always take the head to a shop and have them measure this for you if you don't have a high quality straight edge.($$$) They will likely tell you it needs a valve job depending on the miles. Whiles it's off might have them check it for cracks. You can replace the valve seals yourself.. and then install the head. Quote Link to comment
frey1691 Posted January 23, 2012 Author Report Share Posted January 23, 2012 ok draker that sounds a little better id like to be safe with it just cause it is my daily driver but at the same time i hate that my z22 is taking 3 minutes to get to 60mph so i want to get a fresh clean start and yea the head has over 200k on it so i was thinking a valve job at least and i had thought about getting it decked .010 to raise compression a little but im really not sure of the condition of my bottom end and i really cant afford to break anything considering im lucky to have 70-100 bucks every two weeks to put into this thing Quote Link to comment
Draker Posted January 24, 2012 Report Share Posted January 24, 2012 ok draker that sounds a little better id like to be safe with it just cause it is my daily driver but at the same time i hate that my z22 is taking 3 minutes to get to 60mph so i want to get a fresh clean start and yea the head has over 200k on it so i was thinking a valve job at least and i had thought about getting it decked .010 to raise compression a little but im really not sure of the condition of my bottom end and i really cant afford to break anything considering im lucky to have 70-100 bucks every two weeks to put into this thing I would save for a few weeks before diving in then. Then get a quote for the work and start from there. Things can add up quick! Quote Link to comment
frey1691 Posted January 24, 2012 Author Report Share Posted January 24, 2012 Well how much would you normally pay for this work cause I dont feel like getting dicked over my first time Quote Link to comment
wayno Posted January 24, 2012 Report Share Posted January 24, 2012 Is this a napZ head you are talking about? I am a little confused here, when dual SUs and R1s are talked about, it is usually an L block or more specificly an L head on whatever block is being used. Quote Link to comment
ggzilla Posted January 24, 2012 Report Share Posted January 24, 2012 We recommend you get the Z24 running good with the stock carburetor, then afterwards switch over to dual or quad carbs. Is your 1985 Z24 the one with fuel injection or with the carburetor? Quote Link to comment
frey1691 Posted January 25, 2012 Author Report Share Posted January 25, 2012 ok well the z24 is what im planning to use for my lz24 build so im not planning on having it running for a while but the z22 i have runs ok right now its just REALLY low on power which is why im trying to do this head swap. and idk if the head is the answer but i cant keep up 70 mph in 5th gear i have to be at 75 or higher to hold speed in 5th when im going up semi steep hills i have to shift into the high end(3800-4500rpm) of 2nd or 3rd to even make it up the hill and usually if im in 4th before the hill i end up in 2nd by the top . i will try and get a video on my phone today if it helps and you can hear the truck bogging down and im basically foot to the floor. Quote Link to comment
Guest kamakazi620 Posted January 25, 2012 Report Share Posted January 25, 2012 ok well the z24 is what im planning to use for my lz24 build so im not planning on having it running for a while but the z22 i have runs ok right now its just REALLY low on power which is why im trying to do this head swap. and idk if the head is the answer but i cant keep up 70 mph in 5th gear i have to be at 75 or higher to hold speed in 5th when im going up semi steep hills i have to shift into the high end(3800-4500rpm) of 2nd or 3rd to even make it up the hill and usually if im in 4th before the hill i end up in 2nd by the top . i will try and get a video on my phone today if it helps and you can hear the truck bogging down and im basically foot to the floor. Dude you not even close to redline 4500????? hahahahahaha it AIN'T a 350 Chebby Bro!!!!! you can run that z22/z24 at 6000-6500 all day long not the best millage if doing so but yeah you gots to downshift up hills duh!! its NOT a torque monster like a domestic 6/V8 your gonna have to wined it out Quote Link to comment
frey1691 Posted January 25, 2012 Author Report Share Posted January 25, 2012 i know i have to downshift im newish to datsuns not driving...and trust me i KNOW its not a 350 that was my first vehicle all im sayin is that my 22r 2.4l yota used to book it up hills without any problems at all and im just trying to get the datsun a little bit above that power level Quote Link to comment
datsunaholic Posted January 25, 2012 Report Share Posted January 25, 2012 Shouldn't have to downshift from 75 going up hills. Cripes, I can hold 70MPH in 5th going over a mountain pass with an L18. What kind of hills are THAT steep in Georgia? Something's not right. The Z24 head won't help low-end power at all, and not sure it'll help high end power either. Unless the valves aren't seating. Probably something else- timing is all whacked out, carb isn't running on the secondary, low compression (which COULD be the head, as in the valves, but usually is the rings). The bigger issue is that the intake port design is different between the Z22 and Z24, so swapping would create a mismatch. Quote Link to comment
ggzilla Posted January 25, 2012 Report Share Posted January 25, 2012 Yep. Don't swap heads, it won't help. Instead, try revving it up to 6,000 RPM. She'll pull hte hill. Start with a basic tune-up. Re-gap the plugs, they are probably having a bigger gap than stock. Set the timing to spec according to the sticker on the bottom side of the hood. Quote Link to comment
frey1691 Posted January 26, 2012 Author Report Share Posted January 26, 2012 Ok so the head won't do anything for me? Even with bigger ports cam and valve job? And I replaced my accelerator pump which helped a little and my carb was leaned out a bunch so I cited that too. Also would the jets from the z24 carb give me a little power especially if they are really clean? Quote Link to comment
datsunaholic Posted January 26, 2012 Report Share Posted January 26, 2012 The only thing that doing the valve job would help is if the Z22 valves weren't sealing. The valves are the same size I believe. Bigger ports only help at the top end, OVER 5000RPM. Which won't help much anyway if the valves are the same size. Your problem is not enough power in the 2500-4000 range. Bigger ports and bigger jets in the carb will not help that, all the bigger jets will do is make it run rich, lower fuel mileage, and probably foul the plugs. If the carb was too lean, clean the jets. Super easy on a Hitachi. There's no adjustment for lean/rich other than changing jets (except idle mix which uses the idle mix screw). Have you done a compression check? Quote Link to comment
frey1691 Posted January 26, 2012 Author Report Share Posted January 26, 2012 ok well im glad i asked then that saves me a bunch of money and no i dont have a way to do a compression check at the moment not unless there is a home way to do it. also i know blue smoke is oil and white is gas/coolant but what causes black smoke just carbon? Quote Link to comment
datsunaholic Posted January 26, 2012 Report Share Posted January 26, 2012 Black smoke? Too rich. Carb leaking fuel into the intake, and such, or the idle mix is wide open. Sounds like the carb has some pretty major issues. Could be timing set too far retarded. It sounds totally out of tune. Quote Link to comment
ggzilla Posted January 26, 2012 Report Share Posted January 26, 2012 Start with a tune-up. That will bring it back to normal power. Quote Link to comment
frey1691 Posted February 23, 2012 Author Report Share Posted February 23, 2012 Ok so new plugs new wires more sea foam a weber 38 and it runs the same but a little more power wtf? It idles around 2k-3k and anywhere inbetween(no pattern very random) first and second gear have great power but when I give it gas going into third gear it starts to sputter out. Oh and is there any special trick to timing without a light? Quote Link to comment
datsunaholic Posted February 23, 2012 Report Share Posted February 23, 2012 If it's idling that high you have a problem. Choke stuck shut? Major vacuum leak? Quote Link to comment
ggzilla Posted February 23, 2012 Report Share Posted February 23, 2012 Why did you replace the plug wires? Were they bad? Otherwise replacing parts won't fix the problem. It idles around 2k-3k Part of a tune-up is setting the idle speed. It should be set to about 700 or 800 rpm (check the underhood label). Yes, timing is set without a timing light. The light is only used to check the timing. Refer to your service manual. Don't have one? Your local library will. Quote Link to comment
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