Valve diammeter for L28 Performance head.

[Gav240z]

Hi everyone, just wanted to ask what the general consensus is with performance valve sizes. I have found a set which believe will suit an L28 and are 1.73" intake,(44mm) & 1.49" exhaust (38mm)

Standard intake valves on an L28 are 44mm for intake but 35mm for exhaust.

When you install enlarged valves is it for both sides intake and exhaust or generally for exhaust only?

I'm building quite a wild motor here cam specs will be 300 degree duration and .560 of lift fed by 3 44mm Mikuni's.

Just want to know if these are the most appropriate valves to use?:laugh:

[greenmonster80]

Gavin, I keep finding your old posts when I am looking for something else. I recently purchased a N42 head w/ the oversized intake / exhaust valves. Combined with my big ITB's equals cam needs to be for high revs to justify the mod..Currently looking for a cam to suit myself..Your carbs will be up to the task since you got the 44's...Did you find your rods yet?

[Gav240z]

Hi mate, yes I finally got the rods you can keep up to date with my progress here: http://datsun-240z-blog.viczcar.com/l14-rods-arrived.html

I've only managed to get 4 L14 rods but I got them at a good price. I got them for approx $150 AUD. The same guy who got me those is on the look out for 2 more, however if I manage to find 2 more at a good price I'll go with those.

I am probably going to be using an N42 head aswell. I have found a guy on ebay who I believe sells performance valves to suit L-series heads at a cheap price. They are stainless valves also.

I'm not sure what the largest valves are that you can fit on an L head without major modifications.

[madkaw]

Gav,

bought the same valves on e-bay,good quality by the way. The problem on my e-88 was that exhaust is way big. Granted i am only using a 2.4, the valve was huge and I believe your talking lots of work to put that in. I had the valve cut down to 35mm since that is oversize for a 2.4. You don't realize how oversize it is until you see it in the combustion chamber, that 3mm is almost 1/8 inch.

good luck

[greenmonster80]

Gav, Shoot me your address and I will e-mail you pics showing the valves installed. Huge. Had to reshape the combustion chamber a bit to allow the valve to pass thru. Very impressive looking. If not an overbore piston I do not think it would work.

[greenmonster80]

Looked at your blog...Very cool...Particularly like the little tutorials about the parts. Will definitely help dispell some of the rumors. Especially the rods. So you have a Block Nissan letter valve cover....Interesting as this is whant I need....You are looking for exactly which of the small letters versions....Do I see a trade happening?

[Gav240z]

Gav, Shoot me your address and I will e-mail you pics showing the valves installed. Huge. Had to reshape the combustion chamber a bit to allow the valve to pass thru. Very impressive looking. If not an overbore piston I do not think it would work.

Hi mate send me an email at gavindoolan@optusnet.com.au. Are these the same valves as those on ebay? Or are they just the same diammeter?

[Gav240z]

Looked at your blog...Very cool...Particularly like the little tutorials about the parts. Will definitely help dispell some of the rumors. Especially the rods. So you have a Block Nissan letter valve cover....Interesting as this is whant I need....You are looking for exactly which of the small letters versions....Do I see a trade happening?

Yes my blog is aimed at helping educate others on what I have found. I want to also have some tutorials on modifications such as rear brake upgrades and CV joint upgrades etc..

Yes I have two of those Nissan valve covers I was going to use one to practice my valve cover polishing skills. I can't get to the other one at the moment it's in a workshop. If you really need one of these covers I'm sure I could arrange to get one to you. They both need a bit of work restoration wise though.

[greenmonster80]

Pics sent....Feel free to post them on your site if you feel the need...