Discussion about KA24DE valvetrain

Post by **TD87** » Sat Dec 21, 2002 3:07 pm

Does the KA valvetrain use rocker arms? Also, is the valvetrain limiting the KA from revving high? Should it be upgraded when adding turbo?

Post by **WDRacing** » Sat Dec 21, 2002 3:07 pm

Excellant thread topic. i would like to see some pics of the valvetrain up close. I know somebody on here has to have some. I do know the valve train alone is not the limiting factor when it comes to higher RPMs. But rather the long stroke of the crank. Most stock valve trains are able to easily over extend the stock limit by 500 to 1000 rpm. It wouldn't be good bussiness if the manufacturers made them explode at anything over redline.

However, upgrading is always a good thing. Titanium valve springs and retainers are a good idea.

WD

Post by **TD87** » Sat Dec 21, 2002 3:07 pm

http://www.sr20development.com/Instruct ... KA24DE.PDF

Go to this site. It has pretty good pics of the valve train, and it also tells how to install JWT cams. Now I know the KA doesnt have rockers, but what do u call the KA's type of valvetrain. It just looks like a simple push open mechanism or sumthing.

Post by **C-Kwik** » Sat Dec 21, 2002 3:07 pm

I don't know the exact technical term for it, but the DOHC set-up is a direct lifter. And yes, the cam just pushed down on the lifter. This is considered the most efficient type of mechanical lifter as it has the least amount of moving parts and has the least amount of mass. Less mass means you can run a lighter spring for a given cam and reduce friction on the cam as well as resistance. The lighter lifter assembly also absorbs less power to actuate.

Post by **cnichols** » Sat Dec 21, 2002 3:07 pm

Not sure either, but I've heard it referred to as a direct-acting valvetrain where the cam lobes contact the shims which in-turn contact the valves.

Post by **WDRacing** » Sat Dec 21, 2002 3:07 pm

Its sounds the same as the RB series. Except the RB's don't use shims. The RB has Hyd type lifters. I love this setup, no valve lash to deal with.

WD

Post by **Top Speed Coupe** » Sat Dec 21, 2002 3:07 pm

It is called Bucket and Shim. from what I heard.

Post by **Thesil** » Sat Dec 21, 2002 3:07 pm

so does all this necessarily mean it is better than the sr's valvetrain?

Post by **I am Technoman** » Sat Dec 21, 2002 3:07 pm

Thesil wrote:so does all this necessarily mean it is better than the sr's valvetrain?

Yes.... why? Less moving parts

Post by **wanabe240esx** » Sat Dec 21, 2002 3:07 pm

the sr is like the v-8 pushrod engine of the imports, say it out loud, "rocker arms suck"

Post by **Top Speed Coupe** » Sat Dec 21, 2002 3:07 pm

KAs vavle train is far more superior as for taking a Licking and keeps on Ticking. But when it come to doing Cams and Valve work. GOOD LUCK SIR. You have to do each valve and measure the shims one by one. A hugh pain is the *** if you don't work at a head or machine shop where shims are plentyfull.

SRs are weak due to Rocker Arms snaping or breaking. But I heard of Rockers Stoppers? I maybe wrong as to there purpose but I hear they keep the Rockers from Snapping? And the are easy to do Cams n Vavle work.

Discussion about KA24DE valvetrain

Discussion about KA24DE valvetrain

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