Once apon a time...

I purchased a 95 240sx SE, with 157k swapped with a 1998 R34 GT-T motor and all necessary components, as well as many additional upgrades installed, on January 17th 2009 from a guy in Tennessee, anticipating that i would be able to drive it the way it sat. However, i was horribly mistaken. This motor was fully built with a rotating assembly out of an R33 GTR. This car was running poorly, but running when i bought it. I drove it home back to NC from TN on the 9 hour journey.

The cylinder head was removed and inspected due to excessively loud lifter noise. This revealed that the timing was set incorrectly, causing the engine to overheat. The overheating led to 8 cracks along the spark plug threads all along the head. This head was sold for scrap metal and i purchased a replacement head from a friend in Okinawa, japan.

That head went to the machine shop, got a full rebuild, valve job, the whole thing. Then i came to find out it was the wrong head for my application. It was an RB25DE head, which will not work.

After acquiring a third cylinder head from Okinawa, and having that one built, even more extensively, a factory camshaft broke in half, which led me to purchasing Tomei pon cams.

Shortly after, and i mean like 4 weeks after, the engine spun a rod bearing, detonation melted the #6 piston to the quench pad. This has led me to a full ground up block / head rebuild using only the best components. From here on out, consider this a "start from scratch build".

I took this same 3rd cylinder head to the machine shop, and had it repaired. They welded it up, did a valve job, threaded in a head drain in the back where the freeze plug goes and everything. $630 later... found out that my original problem with the whole build was due to using RB26 pistons and crank with the NEO head combination, yielding an extremely high Compression Ratio. so...

I purchased a COMPLETELY STOCK neo short block, put my neo head with ARP head studs, and tomei cams on.

The rest is history. Inside this thread, you will see the build of my R34 GT-T skyline powered s14!

This idle video shows the poor condition the engine was in when i first purchased the car. http://www.youtube.com/watch?v=T4FVSusJumg

Hope you all enjoy.any help would be appreciated!
Thanks,John

Those aren't hydro lifters. Could be a number of things. Was the head redone? Was valve lash checked?

eh? wrote:Those aren't hydro lifters. Could be a number of things. Was the head redone? Was valve lash checked?

I really appreciate your quick response. i just bought the car from someone that did most of the work. heres a link to his build thread. this is as much as i know about the car.

http://zilvia.net/f/chat/17438....html

heres a thread posted when he purchased the motor

zerothread?id=254268

i also have a question about the Q45 throttle body being used on the greddy mani. is it true that there is a coolant controlled idle system on the TB that needs to be removed for better idle? from what i have read, its like a spring on the left side that can be seen in the above pic.

and heres a mod list BTW. thanks again everyone.

Neo RB25DET out of a '98 R34 GT-T

Block/Head were cleaned and milled to spec, valves adjusted, etc..All machine work done by Revolutionary Performance (RPM) in Mt. JuiletBuilt block stroked with a R33 RB26 GTR Crank, with the good; longer oil pump drive essentially a built RB26 bottem end w/ a Neo RB25 head.

RB26 8.5:1 CP Forged PistonsStandard Forged RB26 RodsARP FastnersACL BearingsCometic 1.1mm MLS MHGGreddy Intake Manifold (w/ modded fuel rail to seat injectors properly)Greddy Oil Catch CanInfinity Q45 Throttle BodyNissan OEM Timing Belt TensioniorNissan OEM Timing Belt Idler PulleyNissan OEM Water PumpNissan OEM ThermostatNissan OEM Intake Manifold GasketNissan OEM Exhaust Manifold GasketNissan OEM Valve Cover GasketsNissan OEM 91 Sentra IACVN1 Oil pumpGreddy Timing BeltOil Return ModPower steering worksAir conditiong does not

Engine/Trans Mounts

Syko Performance motor mount kit. (utilizes the R33 crossmember)Automatic S14 Transmission x-member with Peak Performance Pro Transmission Mount

Transmission/Drivetrain

R34 RB25 Pull style clutch 5 spd manual transTC&S Sprung 6 puck kevlar clutch disc, w/ reworked OEM pressure plateOEM Resurfaced Flywheel1 Piece Aluminum driveshaft.Stock OEM Open Diff

FuelStock Neo RB25 injectorsZ32 Fuel FilterWalbro 255lph fuel pumpNismo FPR

Turbo/Exhaust

Factory RB25 T28 turbo, factory exhaust manifoldHKS BOV ...(SSQV - new version)Syko Performance Stainless Steel Turbow Elbow ( 3" )Blitz SR20 Stainless Steel Downpipe ( 3" )Resonated Stainless Steel Test Pipe ( 3" )Apexi N1 Duals catback exhaust ( 3" halfway, splits to (2) 2 1/4" pipes)

Cooling

Griffin Aluminum RadiatorFlex-a-Lite Dual 12" Pusher E-fans w/ thermostatic relay Hybrid FMIC, 3" inlet, 3" outlet...custom pipingApexi Power Intake

Suspension/Brakes/Wheels/Tires

Megan Racing 32-way adj coilovers, Street editionBattle Version Rear Upper Control Arms.Z32 TT Brakes up front, with conversion lines, slotted rotors

RAYS 350z Track Edition wheels(F) 18x8 +33(R) 18x8.5 +30

Electronics/EMS

CARL H approved engine harness and gauge cluster calibrated to read correctlyER34 Apexi PowerFC Standalone EMS w/ Hand CommanderAEM Tru Boost gauge/ControllerAEM Uego Wideband^^both in dual pillar pod^^ Summit Battery Trunk Relocation KitPower distribution block

Sounds like lifter tick. But one would have to be there in person to tell. I'm curious how they adjusted lash. There are no english instruction for the Neo head..

For the Q45 TB yes, secondary spring needs to be removed to lower the idle if they stock iacv and air regulator are used. Did he remove the stock idle control?

the IACV is from a sentra, and looks like the wiring going to it is not connected, but the hose going to the cold side piping to the throttle body is connected (i guess to provide vac at idle?). i will have to remove the spring. im not sure about the "air regulator". the idle is electronically controlled through the computer on the power fc. it has its own self diagnostic idle set mode which should control it. i dont think theres a need to have the spring on the TB.

I'll have to search for instructions on the NEO head.

i also need to learn about the lash. not sure what its about.

thanks! im getting closer.

valve lash out of whack

I thought you couldnt adjust the valve lash on a motor with solid lifters? not sure though

Yes, you change lash on solid lifters by changing the thickness of the shims between the tip of the valve and the lifter bucket. And lash is the distance between the lifter bucket and the cam as the lobe is pointing 180-degrees from the bucket. It should lightly ride on the cam.

Sad to say, but you really should pull the valve covers and measure the gap between the round part of the cam and the lifter bucket and record the thickness that must be added to each bucket and shim combination. I am guessing that the installer got all the shims mixed together and just slapped them together without measuring.

As a result, the other valves might not be completely closing either because their shim combinations are too thick. This can be checked with a leak-down tester and simply rotating the crank by hand to make sure each valve closes completely.

A lot of work, but if you are religiously methodical about it, you could do it in a weekend and have that baby purring like a kitten.

For the Q45 TB, just remove the idle control spring from the pulley if you are getting surging during idle. Some can run with it and it causes problems for others.

get a set of angled feeler gauges and look at the head specs for the 26 if you cannot find them for the neo25. you need to check the lash like darius said. 2 valves at a time (maybe more depending on phase).

gawdzilla wrote:get a set of angled feeler gauges and look at the head specs for the 26 if you cannot find them for the neo25. you need to check the lash like darius said. 2 valves at a time (maybe more depending on phase).

I'm wondering if that is the problem, they used the RB26 clearances instead of the R34 rb25. Using the RB26 clearances would put it out of spec but I don't know if it would cause a serious problem. Gotta find someone who can read japanese to figure out which is intake and which is exhaust..

Here's the clearances for the R34 RB25 in japanese.

Sounds like one lifter is missing the shim, just take off the rocker cover, it will be obvious which one. AND STOP REVING IT UNTIL YOU PUT THE DAMN SHIM IN IT.

thanks guys, ill have to pull the cover tomorrow and look. if i can, ill take some pictures and post them.

there is a 34 manual on my site, if it does not have the neo head, find out what the clearances are, use the gtr manual, it is done and checked the same way

on my NEO there are no shims but rather the complete lifter bucket will have to changed with a proper sized one. there are an *** load of different sized solid lifters for that engine. the reason that is is that each one of the lifters have a different size to them. that looks like bumbletuna's old ride, was the pass. side fender jacked up at all when you bought it?

yessir sure is. so where in the world do i get a complete new set of solid lifters for this thing? thanks for the reply, as you can see i've been getting varied answers. this makes more sense though. i knew there was an issue with them being shimmed because they are solid.

S14-NEO wrote:on my NEO there are no shims but rather the complete lifter bucket will have to changed with a proper sized one. there are an *** load of different sized solid lifters for that engine. the reason that is is that each one of the lifters have a different size to them. that looks like bumbletuna's old ride, was the pass. side fender jacked up at all when you bought it?

.

S-tec Motorsports wrote:there is a 34 manual on my site, if it does not have the neo head, find out what the clearances are, use the gtr manual, it is done and checked the same way

It is a neo head, ive got the R34 manual on pdf in english but i have not located the section with the clearances yet.

Buying a new set of lifter buckets will do nothing for you. There are several different bucket depths as S14-NEO pointed out. The best option is going to be to install shims on the valves that are out of spec or buy lifters that are sized based on the gap they need to fill plus the height of the lifter on that valve. Basically order a taller lifter where needed.

Or you can pull everything after measuring and try to put the taller buckets on the shorter valves to make up the difference and hope it works out in the end.

I would still try to shim up the shorties.

Darius wrote:Buying a new set of lifter buckets will do nothing for you. There are several different bucket depths as S14-NEO pointed out. The best option is going to be to install shims on the valves that are out of spec or buy lifters that are sized based on the gap they need to fill plus the height of the lifter on that valve. Basically order a taller lifter where needed.

Or you can pull everything after measuring and try to put the taller buckets on the shorter valves to make up the difference and hope it works out in the end.

I would still try to shim up the shorties.

where would i get the shims from? is there a kit with multiple shim sizes i could buy so that i dont have as much down time when the car is pulled apart? is it specific to the rb25 neo head valves or can i get a universal valve shim kit. i guess the clearances will have to be measured with a micrometer to determine the valves that need to be shimmed.

thanks

I'm not sure, but there must be USDM Nissans with solid lifters so look that up. Then, call the dealership or maybe a general parts store like NAPA to see what they have to offer.

Shims are nothing more than small, thin cylinders of metal that rest on the valve tip. All you're trying to accomplish is raising the bucket slightly so that it is touching the cam. There will not be "kits" for this since it will be entirely up to you to measure with feeler gauges and calculate.

before you go out and buy anyhting you need to first measure the lash on each lobe of the cam to see where you are at. some are prob within spec and some arent. thats the only way your going to find out is to first measure...(then measure again just to be sure)

Nissan listed over 70 different size shims for the RB26. Time to start measuring that lash. Let me know if you need any as we have a stash full.

Coolwhip wrote:Nissan listed over 70 different size shims for the RB26. Time to start measuring that lash. Let me know if you need any as we have a stash full.

Alright. It almost sounds like the ticking is only coming from the intake cam side, and could actually only be a lifter or two chattering. could this sound / vibration coming from the head trip the knock sensors due to them being on that side of the block? it seems like the car is running fine and i dont hear any knock audible. my power FC is showing the knocking when i get on the gas at part throttle. it almost seems like it goes away even under slight boost (3-4psi) but when i get on the gas harder it starts knocking again.

this was all observed on a long ride back home the day i bought the car. i havent driven it much at all since then due to the rear main seal leaking, as well as the oil return line, and the alternator is shot too.

im looking for a replacement, it currently has a quest alternator. the problem im having is really strange. i think when i drove the car from TN to NC the alternator was not hooked up or something. when i connect the alternator to its cable, and re-attach the battery, it blows the inline fuse that was added under the hood for the battery relocation kit. so its sitting there disconnected right now. is it possibly that it could have shorted out internally?

Thanks for all the help guys, this is going to be a badass car when its done

i have to be honest with you, i dont beleive its a wise choice on your part to continue to drive it while the ticking is going on..cause not only can the lifters get worn but the lobes of the cam as well..neither one of those do you want..so get it handled before you go driving it any further to prevent any premature wear of the cams ok

it is just one tapping, should not be hard to find

S14-NEO wrote:i have to be honest with you, i dont beleive its a wise choice on your part to continue to drive it while the ticking is going on..cause not only can the lifters get worn but the lobes of the cam as well..neither one of those do you want..so get it handled before you go driving it any further to prevent any premature wear of the cams ok

oh definitely. i have not driven the car at all since i got it home. which i wish i got trailered now. i think ive got the alternator fixed just a minute ago. it kept shorting out because the collar that holds the positive from grounding out on the alternator itself is missing. i made a new one and re-attached the power cable to it. it didnt short out the fuse as its been doing the past 6 times! making progress.

good stuff, progress is always good

yeah, i just wish i could make more. lol. i cant do that rear main seal myself due to lack of space, lift and tools. i'll have to take it somewhere. i will also have to get someone to check the valve lash because i have no idea how to.

OH YEAH and i noticed that where the head meets the block in the very back close to the firewall, there arent any bolts going through on both sides. its the last set of holes in the head/block area and im not sure if they are missing due to clearance issues of not being able to get back there to put them in, or because of something else. im pretty sure that its bad not to have them in, and it looks like its really oily on the block near that area on one side of the motor. anyone have any info on this ?

Also does anyone knowwhere i can find the valve clearance specs for the head? im taking it to another shop on monday and they will hopefully be able to measure and shim where needed. i downloaded the R34 service manual and there is nothing noted about the valvetrain there. Thanks!
Modified by sickness14 at 10:44 AM 1/17/2009

Just to clear up some things:

The image I posted is from the R34 FSM, your not gonna find an English version.There are shims *ON* the buckets. Not under like the RB26. The PN's are different and I'd assume they're not interchangeable..I threw this up quick so you can see. Part code 13201H are the shims.http://www.rbforums.org/r34rb25/cams.html

S-tec Motorsports wrote:Sounds like one lifter is missing the shim, just take off the rocker cover, it will be obvious which one. AND STOP REVING IT UNTIL YOU PUT THE DAMN SHIM IN IT.

I took off the cover, found that on the intake side cam (left one) the last cylinder closest to the firewall appears to have both its lifters the farthest down in the head, looks like its missing shims on both, or has the wrong sized one in there.

here are some pics. the ones im talking about have the covers over the cam lobes at the far end.



Here is one of the lifters that i think is missing the shim

decent job on the pics, i still think you going to have to measure the lash on each one of the lifters to see where you are at...you have from the sound of it at least a couple of them that arent within spec.