Where to buy new valves/springs for my 2V?

[Anonymous]

I'm building up a 221/2V combo for my XT Falcon and need some advise.

The head is currently at the machinists and they are suggesting machining the valve guide bosses to fit EA style stem seals. Has anyone had this mod done and is it worth it?.
I'm also undecided with how big to go with valves. Precision International lists a 1.732 intake and a 1.484 exhaust for the pre-xflow but they cost about au$12-$16 ea.
I have read that it can be dicey fitting big exhaust valves on some chambers and am happy to use smaller sizes to play it safe. What other valves fit and where can I get them?
I am also looking at a new set of valve springs. I'm only running a Crow 63613 with .410 lift so dont need to go overboard. I was thinking 80-90 pounds closed and 150-180 open would be heaps as it wont be revved past 5000. Whats an economical replacement to stock and what retainers and locks would I need to match?
Any info is appreciated.

 

[addo]

Don't want to use the Crow springs and retainers?

The exhaust valve size issue only comes up if you're fitting seats into the head. I personally have seen a head fitted with 1.500 exhaust valves and no inserts, and it was perfectly OK.

 

[Anonymous]

Thanks for the reply Addo.
I'll use the Crow springs and retainers if thats the most suitable combo for the money, I just thought someone may know of other options that come in cheaper. Nothing worse than spending the bucks and finding out some other common-as-muck engine runs the same spec stuff at a fraction the cost .
I notice in the 144-250 forum Xctasy mentioning the use of 1.5 valves causing problems with thin wall castings, this is what I'm afraid of encountering. The head reconditioners I'm using seem to vary in opinions from wanting to stick to standard seat angle, standard valve size "your wasting your time" attitude to "hell why stop at 3 angles on the valve seats" and "30 degree back-cut on the intake valves?, lets do em all!". So I'm really trying to get all my facts straight and get the gear I want so I can go in there with a firm plan of what I want done.

 

[addo]

If you can get the Crow bits at trade, it's pretty good pricing. Retail might be exxy - but who pays it?

You summed up the reconditioners beautifully. Like brickies, they can be a real pain because of their negativity.

 

[TeddyXY71]

If you're doing any headwork, as a minimum I'd get a 3-angle valve job and back-cut the intake. If you're gonna take the head off and get work done to it you may as well get as much done as you can (providing the wallet will allow for it ) Better than thinking about it later and goin' "I should have done that.....!". Even if your engine rebuilder is a little doubtful about it, just ask them to do it. It will give you a little extra in the flow department. And seeing as you're running a 2V, you wont have the 'log' restricting you, so the flow improvement might be a bit more than you could expect from a 'log' head with the same treatment.

That's my two cents.

Teddy

 

[xctasy]

I'm with Addo. I've only ever done an X-flow alloy head with inserted valves, and an iron xflow head with enough iron in it to re-scuttle the Rainbow Warrior.

Let your machinist guide you.



PS

I'm a bit conservative on a good 2V head. My experience with Mini heads, where people try and get the nth degree out of them for vlave size and porting, yielded some pretty poor results. 30 years of leaded, yet cracked exhast seats.

The guys at Superflow used to say it best about Holden 9 and 12 port heads. A head is an investment, and why deck it to 120 thou when 60 will do, or use 308 spec 1.74 and 1.5" size valves on a 202 when a well shaped smaller size valves will work better.

On any log or 2V head, the 1.5" valves won't support even an expanded stock exhast port size. The thermal conductivity drops when you extend the valve diameter, as you compromise on cooling.

 

[Danielson]

The head om my 221 apparently has holden 308 valves fitted to it with windsor valve springs. I did not have the work done but when I looked into it, it all seemed quite feasible, and may be a good alternative as the 308 valves are slighty bigger and I think there stems are also marginally bigger allowing a simple ream of the guides to be done. You will need to check it out for yourself as I did not have the work done.
Regards Dan

 

[Anonymous]

I've got a good set of 308 heads in the shed so i'll pull the valves and have a look.
Thanks for the lead, the way things are going I think i'll end up using stock valves as the head already has inserts on the exhaust and with the thin walls on a couple of chambers I dont want to risk hitting water.

 

[Danielson]

So I ask what valves etc did you end up using ? I to have a 221 and a 2V head that I am yet to fit to it, planned on a dual pattern cam and maybe a little exhaust work yet to get it fitted.
Regards Dan