138 Head

[HYSTERIA]

Can any one give me some advice on building a head for a 138 grey. At the moment the advice I have is to fit EH valves, double valve springs and a mild cam. I was also going to fit steel timing gears and twin carbs. The bottom end is 40 thou over and I was going to shave the head to increase the comp.

Has any one tried a combo like this, I want something that will keep up with traffic but I dont want it to run like a pig.

Any advice would be appreciated.

Cheers
Jason

[nicko]

you dont nesasarily need double springs a better option would be to install valve springs of around 20lbs higher tension ,not sure if they fit but ones from a 186S would be just about perfect spring pressure to stop valve bounce at higher revs when you give it a squirt.there is a few carb sets on ebay at the moment,including mine which need linkages and setting up still.sorry about the plug.

[HYSTERIA]

Thanks nicko, I'll look into those springs. I alraedy have the carbs and manifold setup, it's taken me about a year to get all of the parts together, good luck with the sale anyway.

cheers
Jason

[FCwagon]

Had a set-up similar to what you're wanting on my wagon, but the head was severely ported as well. If you do that, it's a good idea to have the manifold & head drilled to fit locating pins. That way you don't need to stuff about aligning the manifold. The valves on mine  were Chev with double springs but as Nicko said you don't need them on a road car. Your 40 thou bottom end is almost at the maximum limit (60k) so you don't need it revving too high. The best thing I did was replace my crank with one from an EJ. The later crank has a larger oil gallery and is more meatier so doesn't sound as harsh.  Also a good trailer cam and headers  will give you bottom end torque and reasonable fuel consumption whilst moving along at a good pace.
cheers,
Leigh

[HYSTERIA]

Thanks Leigh, I have already rebuilt the bottom end using an EJ crank upon advice from an engine builder. I also have a set of extractors as well so it sounds like I'm on the right track.

Can you remember the grind on your cam, a lot of people are telling me that that even a very mild cam in this engine will not behave under 2000rpm. Does this sound right?

What kind of rpm should this engine handle, so far I have balanced the crank and will do so with the cam as well but am not sure what kind of revs it will handle.

Cheers
J

[nicko]

a mild cam will not behave badly as idle revs should only need to be increased by 100rpm in most situations ,its a different story if you start mucking around with lumpy cams,which mild by definition are not,

[colt]

Jason,
Just for the info, I have 186 valves with hardened exhaust seats, 202 valve springs with the red motor valve retainers & caps. Fairly lumpy cam with triples, it doesn't really idle well below 900 rpm. For eveyday use you would be better off with milder cam & twins.
Colin

[FCwagon]

Hi Jason,
Sorry, it was a quite while ago so I can't remember whta the cam grind was. Your engine rebuilder should be able to advise as I believe there is a standard grind for a grey motor cam to give the performance you're looking for.  It should idle ok with your proposed set-up. I set mine at 650rpm and it had only the slightest rup-rup sound when idling & very little engine movement.
cheers

[HYSTERIA]

Thanks for your help guys, can't wait to get it running.