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Engine builders: Need valvetrain help

76zimmer

76zimmer

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I need to order some valves for my 781 heads. I want to go with 2.19 intakes, and 1.88 exhaust. My head guy said to get 11/32 stems in stock length.
Have you used some to fit this criteria?

Also we chose a Lunati flat hydraulic cam with 213/219 dur @ .050 and .515/.530 lift with a C/L of 108 RPM range of 1000-5500.
 
76zimmer said:
I need to order some valves for my 781 heads. I want to go with 2.19 intakes, and 1.88 exhaust. My head guy said to get 11/32 stems in stock length.
Have you used some to fit this criteria?

Also we chose a Lunati flat hydraulic cam with 213/219 dur @ .050 and .515/.530 lift with a C/L of 108 RPM range of 1000-5500.
Click to expand...

The stock valves are 3/8" stems so you better double check with your machinist and see if he's changing the guides with some with a smaller ID. The 2.19"/1.88" valves are factory sized valves from a different application and are still 3/8" stems.

Make sure you get springs that are meant for that cam. Also MAKE SURE you use rotator eliminators on the exhaust to get rid of the rotators that like to break with anything larger than a stock cam.
 
Hey Scott, he did say the guides are shot, and he is going to put bronze (I think) in them. He said to get the 11/32 stems.
Do you know where to look for them? I've checked the popular parts places, and they don't carry the 11/32 stem valves.

I contacted Lunati about what springs and hardware to use, I'll watch for the rotators. Those are the flat inner coil right?
 
76zimmer said:
Hey Scott, he did say the guides are shot, and he is going to put bronze (I think) in them. He said to get the 11/32 stems.
Do you know where to look for them? I've checked the popular parts places, and they don't carry the 11/32 stem valves.

I contacted Lunati about what springs and hardware to use, I'll watch for the rotators. Those are the flat inner coil right?
Click to expand...

I found them at Summit Racing and there are only two different manufacturers for them.

Intake valves http://www.summitracing.com/parts/MAN-11800-8/

Intake valves http://www.summitracing.com/parts/EDL-9775/

Exhaust valves http://www.summitracing.com/parts/MAN-11881-8/

I would run the Manley valves long before any other brand. Too bad your guy wants you to buy the .343" stem valves because they are WAY more expensive. If i were you i would tell him this isn't a race engine but rather a low RPM truck engine and the stock diameter valve stem size is sufficient in this case.


Here are intake valves with standard .373" stems. http://www.summitracing.com/parts/MAN-10728-8/

Here are exhaust valves with standard .373" stems. http://www.summitracing.com/parts/MAN-10727-8/
 
I talked with Jerry Arnold this am Scott, and he is a race head guy, but I told him that the only ones I could find were way expensive, and he said he uses Ferrea valves...$$$. I should have made it more clear that economical stuff would work well for me here. Well he races competition eliminator, so he has to use the best stuff. I asked him if we could go 3/8 and he said sure....I guess he just figured it, how he would normally do a drag engine... Anyhow, he said he could just replace the guides that are shot, and go with 3/8" stems. Cool. Thanks for the links on the Manley valves. I'm checking them out right now. REALLY appreciate your help Scott.
 
That's cool, i kinda figured that was the situation. If you go to a race shop and don't specify what your purpose is they will tend to go with their style of work since it's what they do day in and day out. Ferrea valves are very good but definately not cheap.
 
I go to this guy because he has a reputation for quality work, and is THE guy to go to for superior head work. I've had other shops in town do work, and for some reason there seems to usually be a compromise in their work. Haven't had that with Jerry.
And he seems real easy to deal with. Just a good ole boy.
 
76zimmer said:
I go to this guy because he has a reputation for quality work, and is THE guy to go to for superior head work. I've had other shops in town do work, and for some reason there seems to usually be a compromise in their work. Haven't had that with Jerry.
And he seems real easy to deal with. Just a good ole boy.
Click to expand...
'
Feeling comfortable with the person doing work for you is the best you can do. Sometimes though you have to remember (as you've found out) that their specialty is sometimes beyond what you might need so unless you specify your application (like you have now) you could be having work done that is more than you actually need. In your case you've now told him it's for a low RPM truck engine and he no longer needs to install expensive parts that are for a race engine.
 
The new valve set:

HPIM1329.jpg


A link to the manufacturer:

http://cgi.ebay.com/ebaymotors/ws/e...0364370249&viewitem=&sspagename=STRK:MEWNX:IT
 
YES! We will be getting a spring set from Comp Cams, Jerry said he wants to put a set of double springs on it, I think because of the valve train weight? (that's why I'm leaving this up to him) They should still be stock diameter, and they have the rotator eliminator too! He wants to check the valves out before deciding on the spring set.
 
So clue me in, why would you want to eliminate the exhaust valve rotator? Is this a BBC thing or is it a general V-8 thing?

Rene
 
tRustyK5 said:
So clue me in, why would you want to eliminate the exhaust valve rotator? Is this a BBC thing or is it a general V-8 thing?

Rene
Click to expand...

It's a BBC thing and non stock springs and those rotators don't play well together (the rotators like to explode into pieces with more spring pressure on them).
 
tRustyK5 said:
So clue me in, why would you want to eliminate the exhaust valve rotator? Is this a BBC thing or is it a general V-8 thing?

Rene
Click to expand...

I never reuse the rotators on BBC's or SBC's. Also, Scott is right, intake valves don't use the rotators, they don't get as hot as the exhaust valves do.

Martin
 
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