Valvetrain upgrade, I'd appreciate your counseling.

[dochidalgo]

The engine is almost stock (ported and polished heads, 0.039" Fel Pro head gaskets). I do not want to upgrade the cam, chain time etc; the stock ones has 55 k miles.
I want to upgrade the next parts but I'm truly confused about which types or brands are better for my street daily car:
* Roller rockers 1.6: non self aligning or self aligning (stock ones are this type,right?)? I don't want to replace the valve covers
* Pushrods: 7/16" or 3/8"? hardened or not
* Guide plates or not? My stock engine has not guide plates, right?. I recall the stock head gaskets had a guide holes, but the Fel Pro has not them.
* Springs: LT4 or another brand?
*New locks and retainers too?..are they necessary?
I don't need a 500 HP engine for street now or in the future.
Thanks to clarify mi mind about this upgrade
Regards
Doc
My car has this mods:White 97 Trans am A4, Ported&Polished OEM heads, 0.039" Fel-Pro Head Gasket,
Air Foil, !TB, K&N FIPK, SLP "2on The Left", Random Tech dual converter Y-Pipe,
March Pulleys Set, LT4KM, 160º Thermo, Fast Chips Reprogramm, B&M Tranny
Cooler, BMR Tower Brace & tubular SFCs, SLP Panhard Bar, SLP-Bilstein Shocks,
Spohn Adjustable Lower Control Arms,Torque arm & Relocation Brackets,Prothane polyurethane bushings & end links,GM 1LE Springs & Sway Bars (32mm front & 21 mm rear) kit, GM 1LE aluminium DS, Russel&Earl's 5 SS braided brake lines, KVR X-Drilled & plated Rotors, Raybestos ceramic brake pads, Bridgestone Potenza RE730, Hella H4 Euro headlights with 100/80 Xenon bulbs, Deutsche Xenon fog lamp bulbs,GM silver plastic wheel lug nut covers, Black Bat-Decals, GTS Solarwing II, Ken Collings' Fog Light lens covers, & Joe Bowen's Fog Light mesh covers

[fastTa]

Hey Doc, LT1's use a standard SBC type pushrod. 5/16" diameter and .080" wall thickness. A 3/8" push rod is usually used in big blocks or heavy duty small block apps. A 5/16" hardened pushrod would be just fine for you if you wanted a stronger pushrod to go along with a 1.6 RR. The chrome-moly's are better but much more expensive.

The NSA(non self aligning) rockers are stronger by design but will require the use of a push rod guide plate. The self aligning rockers use a washer in between the roller and the rocker body. Either one of these rockers can cause slight interferance with the stock LT1 valve covers, however with just a few bends of the drippers on the inside of the valve cover you will have plenty of clearance.

If you are going to be using your stock cam, the stock intake valve springs will be OK, but due to the slightly higher lobe lift on the exhaust side of the LT1 cam, the exhaust valve springs will be close to coil bind. I think it would be a good idea to use something like a Comp Cams 986-16 with a spring rate of 296 lb/in which would be OK with your stock cam. It is very important to match your spring rate with your cam, so the springs will depend on whether you decide to stay with a stock cam or go with a bigger one.

GM rates the LT4 spring to handle .540" of lift but that is actually a little conservative. The LT4 valve spring has a solid height of 1.220". This is the height of the spring completely compressed. The normal installed height of the LT4 spring is 1.780". So if you subtract the solid height from the installed height, you actually get .560" before coil bind. So the LT4 spring would work as well but it would be cheaper and better to go with the CC 986-16's.

Unless you really planning on revving the motor over 6000 RPM, i wouldn't worry so much about going with titanium retainers and locks. If you changed valve springs your stock locks and retainers can be re used. I would replace the valve stem oil seals while I was there though.

Racenet Performance has an excellent deal on a complete LT1 valvetrain package:

http://www.lt1f-body.racenet.net/valvetrain.php

[dochidalgo]

Kevin, so do you recommend to me the NSA roller rockers over the SA ones?. I don't want to upgrade the cam yet and I don't expect to rev the engine over 6000 RPMs .
Thanks a lot man
Take care
Doc

[fastTa]

Kevin, so do you recommend to me the NSA roller rockers over the SA ones?. I don't want to upgrade the cam yet and I don't expect to rev the engine over 6000 RPMs .
Thanks a lot man
Take care
Doc

Yes, the NSA's will give you much more effective lift at the valve which in turn will yield more power. Just remeber that these use push rod guideplates and you must use a hardened pushrod with these guideplates. I would also use the 7/16 rocker arm studs as well. They will not flex as much and again will provide more effective lift.

[dochidalgo]

Got it!
Kevin,thanks a lot again
Take care
Doc