VitaminZ

guys from your experience with valve springs and using a cam with .525 lift and 300deg duration , im wondering if I need stiffer outer and inner valve springs ? Advice from whitehead says that running both inner and outer stiffer springs tend to wipe out the cam lobes from too high seat pressure , so they just run stiffer outer springs and stock inner . whats your thoughts on this ?

Yeh I'm over the head now it's a loss bad purchase on my path . I think I will stick with the n42 I have valve reliefs on the Pistons should be ok

Thanks, yeh I'll try selling them

Thanks John , I have a 3.9 sti diff with a Cusco 2way LSD , I would really like to change the final drive to 4.1 or 4.4 though,Would you also agree with the engine builder that the valves are too big ? They also told me they were the wrong length

It's probably also worth mentioning I purchased a built N42 head from a member on here who claimed all the parts were kakimoto racing , and the purchased the head from Ron carter , I mean all of this could be true I really don't know anyways he wouldn't give me all the specifications on the cam or valve train , I guess that should have been enough red flags to not buy the head , anyways I did , when I passed it on to whitehead this is what they told me below about it . Big valves have been installed. 38ex/46in . The seats and valve contact surface have been cut without a lot of margin so there's a sharp edge on the valve. This can create a hot spot that can promote detonation and it also reduces heat transfer from the valve to the seat, which can increase the chance of burning a valve. In normal use it should be okay. There are erosion pockets in 2 of the chambers The cam has .525" lift and likely close to 300 degrees duration. This is a full race cam and will not be street friendly. The head has upgraded valve springs both outer and inner. We run just stiffer outer springs and stock inner springs as we find having both stiffer outer and inner tends to wipe out the cam lobes from too high seat pressure. They have used stock lashpads and instead played with the valve installed heights to get the rocker arm geometry correct. This is not the best way to do this as changing out the cam may make selecting the correct lash pads difficult to set the new cam up with proper rocker arm geometry. The combustion chambers spec out at 38.4cc's which is small. This will require a 2.5mm headgasket for 10.5:1 compression. They tried fitting the head to the bottom end but got a lot of valve to piston interference so they told me its best not to use it which I didn't . So now the head is just sitting doing nothing so I'm thinking of just using the cam from it . Such a waste all the other parts .. Couple pics of the head below

Thanks John appreciate the advice . But I'm guessing I should get SS valves? And I can get away with just a street port basically no heavy porting needed ? That rpm range sounds good to me.sorry for the dumb question but how do i choose lash pad thickness and what size valve spring shims to use ?

Well I know this is a topic that has been discussed over and over again , I have read numerous threads on this but no engine is built the same so I thought I would start my own thread on this to get some assistance and advice on choosing a camshaft that would be suitable for my engine . I have a 72 240z with a N42 motor , bottom end has been built by Whitehead performance here in Toronto . Bottom end is now 3.0L , compression 10:5:1 , valve reliefs on the pistons . I have triple 44 Mikunis with no vacuum advance , runs great no hesitation throughout , no upgraded ignition , still the 280 unit. I chose not to do any headwork at the same time as rebuilding the bottom end due to not having the money to do all together . Engine has been running now for 3500k , very strong , now I would like to bring it to life with headwork . I will have a machine shop do all the work , and I will just provide the parts . My objective with my car is not a daily driver , I don't drive the car in winter for obvious reasons and in the summer I do drive on the street , and next year hoping to compete in time attack events and attend track days . I am not trying to have the fastest car on the track , I just want to enjoy driving my car and really bring out the potential of the motor as much as I can . I really do not have a lot of knowledge about rebuilding a head and what springs , retainers , cam lift , valves I am going to need to be able to bring up the power . Basically can I get some advice on a semi race / performance street camshaft that has been proven , valve sizes , spring setup , lash pads, I would really appreciate it...

Anyone have a aluminum rad for a 240z they would like to sell ? Thanks

Well I've been doing some reading on the Cusco LSD experiences and apparently many other users get this clunk from them . I'm going to change the oil to specific cusco LSD oil which seems cure it a bit and see what happens .

Yeh I've done that but couldn't find anything loose . You're right if that stub axle came out on its own whilst turning it should stay out . I think I'm going to have to check the strut assembly again . Thanks for the insight .

i feel something is moving outward toward the wheel when I turn left and change gears ,1st to second it happens on initial take off at low speed and the clunk is loud enough for me to hear it yes . I haven't really been going around corners that fast on the street to change from 3rd to 4th . Yes I have checked the strut bolts and gland nut . I have not checked the hub.

Ok so anytime i make left turns in low speed and change gear from 1st to second whilst turning I get a clunk coming from the right rear end . Only happens when turning left and only if I change gears . I have checked all bolts under there and all are torqued, I recently changed out all my bushings so I know they are all good . I have installed a Subaru R180 diff which has a 2way Cusco LSD in it . And I am running the beta motorsports stub axles . From the video below you can see I can move the stub axle at the diff outward with very little effort . I am guessing this is causing the clunk since I cannot move the left side ? Should there be this much play in and out coming from the axle yoke ? Couple questions , are both Axles the same length and could this be a bad u joint ? Could I have a worn or broken C clip ? I know its in there since i feel resistance when pushing the stub axle inward until is passes the c clip and seats in the groove on the stub axle. any ideas on this before I start taking everything apart would be great , thanks !!

Anyone have a set of strut tower braces for sale ? Front or rear or both and willing to ship to Canada , thanks .

mods please delete , found item

Anyone have a set of wide zg flares for sale for 240z? I already have the normal zg , really just need a pair for the rear , let me know thanks .

Yes i know T3 sells them ...

Anyone have adjustable front lca and tension rods for sale ? thanks.

Hey guys , looking for a set (6) Velocity stacks / air horns for my 44mm Mikunis , outer horn diameter should be 64mm to be able to fit my BBR filters . Let me know what you have , thanks !

mods please delete

Anyone have a ATI super damper they are willing to sell ? Part #917790 thanks

Before I purchase a new set just checking to see if anyone has a set of T3 rear control arms for 204z for sale . Thanks

bump .. anyone ?

please close admin

Before i purchase one new , just checking to see if anyone has one here for sale . L28 ATI super hramonic damper , thanks.

i sent it to your pm a couple days ago .....