Jump to content
SAU Community

Recommended Posts

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

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.

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.

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?

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.

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

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.

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 :(

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

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

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...

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


  • Similar Content

  • Latest Posts

    • Possibly avoid using a Cometic one unless the deck/head surface are perfectly flat. I did have a look just then and forgiving gaskets such as Tomei or Nitto don't exist for the FJ20, however the Bar-Tek or Kameari ones look good and might do the trick.
    • Because pipe threads for pipe things. M threads for bolt things. Throw some teflon sealant onto it and dust your hands off knowing you did the right thing, instead of going twice around the block to achieve a result using the wrong things. Of course, all of these solutions are ignoring the fact that the minimum thread pitch we're talking about here is 1.25mm, with the 1/4" in NPT or BPS being out around 1.4mm. You will need to know that the boss you're tapping has enough thickness for at least a few threads. That's one of the reasons that 1/8" is commonly used - because the pitch is <1mm. And why would you look to use 1/4" NPT in a BSP country anyway? Ugh.
    • Just throwing around ideas, does it need to be in the compressor cover? Why not the hot side piping?
    • 1/8NPT drill size = 8.7mm. Since the hole got messed up by me, it’s probably around 9mm.    So 1/4” NPT would be next step. A drill size of around 11mm would be preferred there which is not way of my M12 (drill 10.5mm and tap M12 threads) 
    • 3 Kids are starting to hit that ages. I wanted to get them something special to learn on, put down the screens and have some fun. 4Door 2001 R34DE Black Pearl GV1 Jap Import, AU 2nd owner. Pre Work done. Suspension - Wheels Pedders SportsRyder Coilovers   Wheels TSG Spokey Boi 18'x9.5"+15 Body JASI Aero 4 door Type R Full Kit LED Conversion - Parker, Blinkers, & Reverse Exhaust Hurricane Headers 100 CPI high flow cat 2.5" Piping Cannon muffler Internal Bride low max stradia ii - front seats  Bride RO seat base and Rails (R/H) Cube short shifter LED Conversion - Interior   
×
×
  • Create New...