anyone lighten your valve train?

lessonintorque

Registered User
Im wondering if any of you have done the necessary mods to your valve train to raise your redline and get a little more top end? if so what was your setup?
Mike
 
The stock SC valvetrain is heavy for sure but the main rpm limiter for these motors is the blower and not the valvetrain.

What you could do though, is get a new cam from comp cams and run their super lightweight solid roller lifters, get Randy Baker to make you some carbon fiber pushrods, and then use aluminum rockers on top of conical springs and titanium valves. That would be good for 8000rpm but your blower would never manage that. LOL

Also the crankshaft is a big problem. A billet crank takes about 20lbs of the rotating mass as does a lightweight converter or flywheel.
 
If you lightin the valve train.You then can run less spring pressures.With less spring pressures you gain horse power.The valvespring pressure rob a lot of horse power,and the speed the motor can rev to its peak usable power.

Stiegemeir has some larger titanium valves,spring collars,ect to use in a SC head. If your looking for a place to buy lighter SC valvetrain parts.And have
the parts set up and expertly installed.

Randy
 
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dave, you say that the blower is the main part of the problem. Would a magnaport II w/MP plenum allow more power in the 3500-5500 rpm range? I remember talking with you about the m90 and how it relaly isnt a very efficient blower for high HP/high rpm application.

thanks for the input
 
A ported blower does help, but consider that 5500rpm is not high rpm by any standards. High rpm is above 6000 and the M90 doesn't really like that very much.
 
If an m90 isnt a vable option for a hair dryer at high rpm's what about a whipple? I just know the great gains you can get from a higher redline and a faster rev is always better of course. My main question is has anyone expeiremented with this, I havent heard much discussed about it. And thanks for the info Ill check out stegmier for the valve train.
 
A ported blower does help, but consider that 5500rpm is not high rpm by any standards. High rpm is above 6000 and the M90 doesn't really like that very much.

I understand that 5500rpms isnt high, by any mean.(used to have a 90 Crx Si that is didnt shift until 7000!). So basically the m90 isnt built for anything over 6k RPM , am i correct? Even so, there are some other factors stopping the 3.8SC from revving, such as the crank to name one. I don't believe there is another option but the stock crank right?

If an m90 isnt a vable option for a hair dryer at high rpm's what about a whipple?

Talked with dave first hand and he said the whipple was the exact opposite to the m90. rather than getting just that low end grunt like the m90, the whipple just keeps powering you to the back of your seat into the RPMs. Where as the m90 just runs out of wind.
 
The M90 peters out at 5,000 or so as is...You could viably run a larger pulley and rev a built up motor to a higher RPM....However I dont think the M90 could keep up air wise at higher RPM's....High I mean anything about 6000..A twin screw that moves more air however can....REgardless a lighter stronger set of rods/pistons and conical springs with titanium locks and retainers would help regardless.
 
I always thought you needed stronger springs in a higher rpm setup, such as the dual and triple springs used in built drag motors to prevent valve float. Or do you mean lighter by the valves/pushrods/rockers?
 
With a conicle spring setup you dont need a double or double spring with dampner to ward off valvefloat.less weight also means you need less spring pressure
 
Ive decided to go ahead and get a lighter setup so ill let you all know how they work,at least ill be ready for a better blower and possible a higher redline with it. thanks for your replies.
 
FOH thats sweet it will be interesting to see if one of the car manufacturers make that production. 14000 redline sounds good to me :D
 
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