Jump to content
SAU Community

Valve Clearances For Tomei Cams In A Neo

camoo

By camoo,
in Engines & Forced Induction

 Share

Recommended Posts

camoo Collaborator

camoo

Posted
Posted

Im about to install some tomei type b cams into my r34.

So ive done heaps of searches and it has returned multiple answers...

Does anyone know for certain the valve clearances to follow?

Ive got tomei's specs, nissan workshop specs, under my bonnet the sticker has different specs.

Just looking for some reassurance with which ones to follow, and the searching is doing my head in.

Cheers

kitto Mentor

kitto

Posted
Posted

What are the TOMEI specs for those cams out of curiosity?

I've heard they are quite large.

People have thrown shims with those cams and i'll bet its because of incorrect shim clearance.

Nissan workshop manual states it is 0.31 +/- 0.04mm on the inlet and 0.5mm +/- 0.04mm on the exhaust.

JustinP Mentor

JustinP

Posted
Posted

If I remember correctly (I recently installed the same cams), Tomei says the correct clearance is 0.4mm (intake and exhaust). Seemed quite large, but who was I to argue with the manufacturer :P So thats what I set mine to. I also installed stronger valve springs.

kitto Mentor

kitto

Posted
Posted

Yeah i put stronger valve springs in mine as well. But i'm only using stock cams for the time being.

Did you set your shim clearance with new shims, or did you rebuild the head and grind the valves down?

JustinP Mentor

JustinP

Posted
Posted

Yeah i put stronger valve springs in mine as well. But i'm only using stock cams for the time being.

Did you set your shim clearance with new shims, or did you rebuild the head and grind the valves down?

I'm not actually sure, I had the whole head rebuilt / reconditioned by someone and they set the clearances.

The Dan Grand Master

The Dan

Posted
Posted

Yeah i put stronger valve springs in mine as well. But i'm only using stock cams for the time being.

Did you set your shim clearance with new shims, or did you rebuild the head and grind the valves down?

Valve regrind, then get your machinist to trim the valves to get the right clearance. If you get stuck and need some, Precision Shims Australia have them

wolverine Grand Master

wolverine

Posted
Posted

From memory we set them up at 0.016" intake and 0.014" exhaust.

That's about 0.4mm intake and 0.35mm exhaust. If you set them anywhere near 0.018"-0.020" it will be noisy as hell

Mine were re-shimmed to Tomei spec 0.45mm in/ex and there is a bit of noise coming from them. Maybe noisy as hell is a matter of opinion but I would run tighter clearances in future.

JustinP Mentor

JustinP

Posted
Posted

Mine were re-shimmed to Tomei spec 0.45mm in/ex and there is a bit of noise coming from them. Maybe noisy as hell is a matter of opinion but I would run tighter clearances in future.

Ahh yes it was 0.45mm... Which is what I set mine too. Hope mine are not too noisy when I get it going :(

Cyifly Community Regular

Cyifly

Posted
Posted (edited)

I have stage 2 Tomei poncams I'll dig up the receipts and find out what mine are can't remember lol but my head and everything was rebuilt when cams were put in. Oh I'm tuning r34 gtt neo you will love how it sounds when you got em in I know that much

Edited by Cyifly
camoo Collaborator

camoo

Posted
  • Author
Posted

hahaha once again I have been given several different answers.

Thank u all for the advice though.

Any more experiences?

The size tolerance you used and if it was noisy or not?

Thanks again

Cyifly Community Regular

Cyifly

Posted
Posted (edited)

Do you mean noisy exhaust wise? Or as in engine cause mine is noisy exhaust wise.

Engine does make a lil bit of noise can really hear when the cams are ticking over. Hope tht answers your noise question

My poncams as per receipt:

260 degrees 9.15mm intake

260 degrees 9.15mm exhaust

Off engineering receipt:

Was machined 20 thou over by memory

List:

Modify pistons to neo spec

Repair can tunnels

Supply retainers and locks

Machine crank and fit sleeve

Supply and fit valve guides

Hot tank engine

Port head to race

Supply valve springs

Fit oversize inserts

Supply inlet and exhaust valves

Bore and hone block

Modify oiling

Supply rb25 crank shaft

Drill and tap oil gallery's

Manufacture seats

Deck block

Manufacture vernier gear

Assemble Aline pistons

Engine balance race bearings

Arp head studs

Seals

N1 oil pump

Welsh plugs

Not sure if that will help at all man but yea.

Was all done at Jhh engineering in Woodbridge Queensland.

Perhaps give em a call cause rb25 rebuilds are what they specialize in race spec.

0732086274

If anyone will have The answers they will just can't remember that far back.

Edited by Cyifly
  • 2 weeks later...
camoo Collaborator

camoo

Posted
  • Author
Posted

Hey all just an up date.

I checked the clearances and all good, used Nissan spec and they were all within.

The valves are making a decent tick though. Not horribly loud, just enough to be annoying.

Made just over 300 with no loss in response.

So prettyhappy

Thanks all for your responses.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • dyl33
      VOLK RACING GTC CENTRE CAPS

      By dyl33 · Posted

      Centre caps $250
    • Kapr
      Boost cut after swap(RB25DET NEO) R34

      By Kapr · Posted

      Hi. Sry iam not a mechanic and iam not at the car atm so i dont know 100% but they told they measure those and even try to change those. AFM they have two. Coils are new a they have my old one too. Plugs too. ECU...we have 25 NEO stock and Nistune 25 NEO.   But i dont know if any one those could be the problem and why/if/what can cause this, Only thing they did not check is fuel...but that walbro 255 is new(like 1,5 years)... That fuel pressure gauge idk...but i let them know Any suggestions?   EDIT: how can they know if it is like you say he ECU pull power when it reaches a specific boost level that is too high? Tha car has boost controler
    • Duncan
      Boost cut after swap(RB25DET NEO) R34

      By Duncan · Posted

      Can you clarify what you mean by boost cut, do you mean it misfires both when under load (driving) and when stationary and out of gear? Or does the ECU pull power when it reaches a specific boost level that is too high (boost control issue)? Does it occur at idle with no throttle? When you say "the ECU is OK", what ECU is it and why do you think it is OK? Have you used the NEO ECU, and if so do you have a MAP sensor attached? Same for the AFM, why do you think it is OK? Do you have any way to put a fuel pressure gauge on it (even just a mechanical one between the fuel filter and fuel rail)?
    • Kapr
      Boost cut after swap(RB25DET NEO) R34

      By Kapr · Posted

      Hi.. Just another problem. So maybe you can help. I(my mechanic) done swap from my RB20DE NEO to RB25DET NEO. Everything is OK but we have a boost cut. Coils/Plugs are ok...AFM is ok. ECU is ok. I have Walbro 255 but it "changed" sound few months ago(you can hear it ouside) you did not hear that when it was new(maybe faulty?) Sooo...what now? What can cause this boost cut? It is even when you standing still...
    • BOLGE
      R34 Plug Identification

      By BOLGE · Posted

      legend thanks mate !
×
×
  • Create New...