2.02 or 2.055 valve?

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moparduster

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Im running a 360 stock stroke, rods, 10.5:1 pistons. RHS heads. Mainly race with a little street. First ? would you leave it the 1.92 or go bigger. 2nd ? is would you go to a 2.02 or 2.055 (price would be the same). My machinist is charging me $40 to cut for bigger valves and would be 140 for a 3 angle 190 for multi angle. 3rd question is it worth the 50 bucks for a multi over the 3 valve? and info would be greatly appreciated. thanks
 
Do the multi angle.
I myself would also yeild at 2.02. It's a rare day for a 360 to need a larger valve.

The engine build specs are what is really needed here. 10.5 is a low compresion for a race ride. If you were up another 2 points and in a dead out light weight right race car...it may change.
 
The 2.02 should be plenty. Down the road at some future valve job if you need to raise the valves in their seats the 2.055's or 2.08's can be fitted.

Also, if your machinist uses a Serdi machine the seat labor should be the same regardless of profile. If the extra 50 bucks gets a back cut on the valve itself it's worth it.
 
thank yall for your input. What length sould I run, this is my first time buying bare heads and building them up.
 
2.02's should be plenty. I have 2.055's, and think that I probably could have achieved close to the same results with 2.02's, possibly made the power at lower RPM's than I am. They were supposed to be 2.02's, but somebody screwed up and put in 2.055's. I think with the bigger valves, there would be more shrouding, which would negate the added flow. Also, you lose velocity with the bigger valves. I'm no expert by a long shot, these are just my thoughts.
 
Length? Valve length? If you need taller springs than a stock set up, all this will be easy to seen and adjust with the machinest. Stock height springs are good for alot of spring pressure and performance power making engines.

When you start getting nutz on power, 1.6 - 2 hp per cube area, taller valevs come into play.
 
im running a purple shaft .320/.320 advertised .533/.533 lift and running the double spring that mopar recommends.
 
It cost more but I went with the 2.05s, multi angle and a taller small stem chevy guide size for the valves. I needed a taller spring my lift is near .600, but again I have a stroker too.

it did required spring seats, shims, guides etc to make it work, but will get a little more flow.

However, if cost is an issue 2.02s multi I agree :)

NOTE on the 2.05s you start to get into a little bit of shrouding issues, y 340 has a bit larger bore so maybe it is not as much an issue:) ?
 
moparduster said:
im running a purple shaft .320/.320 advertised .533/.533 lift and running the double spring that mopar recommends.
Click to expand...

that is a big hydraulic cam...

gotta need some gears and converter...
 
Brian (ou812) at IMM was running a 360, stock internals (except pistons) 12.2:1 compression, W2 heads with 4.56 gears hitting mid 10's. He hit high 10's with his Car Craft stroker with RHS heads (2.02). I don't think the RHS heads were ported. You might want to call him or PM him for some info, he knows what he is doing, and does a lot of R&D.
 
2.05's will in turn end up having more bowl volume, which could be good for stroked/cid increase over a stock cid.
Yes there can shrouding but when going to larger 2.05 you could say/assume you'll also have more flow 'depending', for if you're going 2.05 you would most likely have high flowing heads-280 or better with factory iron/rhs or 300+ with w2/5 or indys etc...
So in other wards...the cfm loss from shouding/or effect of the eddies seen form the air crashing and backing up could be offset say if there were only certain expectations that the heads over shoot to begin with in power when having that much cid to feed.

hope you guys get what I'm saying.

really if the heads are good for what you are doing the 2.02 should be enough.
but there are always variables, like someone removing too much from the bowl area or farside bowl area....now that 2.05 looks good cause after cutting for it, you gain back lost bowl material to work with .
 
when et's come into play, theres a big diff between a tuned chassis race car and your daily driver.

A really good working chassis race car need less power to run where high powered street cars run.

wish mine worked as good as brians.lol
 
You should be more than happy with the original 1.92" and 1.625" size. I've gone 11.31 @ 3,540 lbs and there are lighter 360's that have been well into the 10's with 1.88"/1.60" valves with OEM heads - not ported, less cam lift and 10.5-1 compression! You can always go bigger later, especially if you upgrade the rest of the combo also. For now I think you could use the extra velocity and bottom end from the 1.92" valves. Valve job is much more important, although I believe they come with a factory valve job already. Just not sure how good it is. Have it touched-up. Comp Cams has .100" longer than OEM Magnum valves available at 1.92" and 1.625". The longer valves will open up your spring options. The heads are based on Magnums and the LA-X and LA-M are exactly the same, except for being machined for their respective rocker arm set-ups. OEM Magnum valve lengths and installed heights are shorter than typical LA heads. But you'll have to measure the installed height to see what you end up with first.
 
If its a street car with just a mild motor,318 heads on the 360,small valve head and it will keep the air speed up faster than using the 202 valves,mrmopartech
 
first go with the larger valve it help you out on the high end

second the cam you are gonna use will need more stall
than 3500 at least 42 to 4500

I usaed that cam and it didnt have any bottom end
centered in any way to much duration

and if you get more cr. will say 11.5 to 12.0
it will get more hp and torque

my 2 cents
 
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