Evo valvetrain weights

[CutlassJim]

EDIT: I had the numbers all nice and lined up but the forum makes all my spaces 1 space and effs it all up so I threw a / in there. I like that effs doesn't set off the spell checker. /ubbthreads/images/graemlins/smile.gif

I'm building up a second head for the Galant and I'm going with an all Evo valvetrain again but this time I got all 9 valves so the exhaust ones are sodium filled. Just for the info I brought them to work and weighed everything versus their counterparts. The head is off a 96 so everything listed is 2G which I'm almost positive is the same as a 1G/GVR4.

The scale at work is accurate to 1 gram and I took the average of 3 for every piece measured.

DSM / Evo 9
Intake valve 55g / 55g
Exhaust valve 54g / 45g
Retainer 15g / 4g
Keeper (Set)(reusing stock) 2g / X
Spring 55g / 40g
Spring seat 4g / 4g

So for weight the springs need to control (Valve + retainer + keeper)

Intake 72g / 61g savings of 88g for set of 8
Exhaust 71g / 51g savings of 160g for set of 8

Total weight

Intake 131g / 105g savings of 208g for set of 8
Exhaust 130g / 95g savings of 280 for set of 8

Total weight savings of 488g or 1.08 lbs. Not much but combined with the higher rev ceiling of at least 7500 rpm (more like 8k) and the extra heat transfer of the sodium filled exhaust valves I think it's more than worth the $100 investment and more than enough for a sub 500hp head.

I am still in the process of porting and junk but will probably do another post on some of the tips and tricks I've come across scouring the net after I'm done.

While I was at it I also weighed the cam gears I had at my disposal.

1G 5 spoke 510g
2G 4 spoke 527g
2G intake (with ring) 707g
AEM adjustable 400g


Not sure if anyone cares about this stuff but there you go. I'm posting this on a few forums so the info is more accessible. Cheers!

 

[JSchleim18]

What about Evo rocker arms? I have a set at work with a postal scale that was recently calibrated. I can weigh them if you'd like?

 

[CutlassJim]

That would be great. I wanted to see how much if any difference there was between the new and old style rockers.

 

[curtis]

The old cast rockers vary in weight from 39 to 44 grams each, luck of the draw. Then the evo rockers are stamped steel and pop in at 50 grams each and are usually with in a gram of each other over the 5 or 6 sets I've checked. I've lightened a few sets of the cast ones and got them down to 36-38 grams each for the whole set but haven't attacked the evo ones yet for my build but looks like there's plenty of material that could be knocked off and I believe they could go down to 35 grams or so. 420a neon motors look like the same thing and ratio but don't have a hole for the oil to squirt from but a small drill bit would solve that. But would be something to experiment with first so you don't screw up a set of evo rockers trying to get them below 35 grams each, neons are at every bone yard.


Chris Beren contacted me years ago and wanted to see about me writing code for the mill to get the cast ones super light because Mike kept flinging them off the evo at plus 10K rpms. Also looked at ceramic bearings but cheapest I found was around 2K for enough to do a set of rockers. After destroying 4 or 5 ball end mills I stopped the process. I came to realize that they must be a hard steel alloy or hardened after being cast and chucking the little turds up in the vise was the biggest problem. With the weights of everything from the bearing catalog pdf and the one I did cut down we could have had followers under 20 grams each but is 2500 worrth the effort. I say turn up the boost one psi. /ubbthreads/images/graemlins/devil.gif

Now as for lightening them up it just takes time. I went to harbor freight and bought a 10 inch dia, thick grinding stone and put it on the table saw, it looks like a triple thick cut off wheel. I weighted them all and wrote down the numbers below each one and started with one side from the bearing to the lifter. Did all 16, then the other side then the rear sides then the ends. They get hot fast and you don't want to push the process and weaken the steel. large cup of oil oil helps keep things cool. Every set I've done the buyers said that it seemed to rev smoother and faster. /ubbthreads/images/graemlins/dunno.gif Total weight loss is probably 60 to 80 grams depending on how close and light the ones you have are. Its alot easier to start with 5 or 6 sets and match them up and go from there but in theory it should help being lighter and all being matched with in a gram to each other. All forces on the cam being uniform will help.



Something else I noticed looking at my buddies 32 valve ford motor is that the ford 5.4 4.6 motors have a similar rocker to that of the evo. Not sure if the bearing od is the same or the ratio is correct but just look similar. Need a set of calipers and two side by side to tell.