What are symptoms of #9 or #10 camshaft lobe wear?

[TGP Nick]

So you are saying springs will or wont help? If they will help, which ones in your opinion and what would the benefit be? Thanks

Springs won't help you on a stock application.

[RICHTGP]

When you say stock application are you talking about stock bottom end and turbo? What if I am changing the cam? If I'm only upping the cam maybe I can leave everything the same and just change the cam and lifters. Any power increase this way?  Thanks for any input.

[flybynite]

Springs won't help you on a stock application.

ummm yes they will... All tgps experience valve float @ or around 4800rpm... Also I agree that the LIM sucks but we are forcing air through it so it will flow decent #s above 5k and don't forget that the smaller runners also create velocity..... For injectors I would recommend some Bosch design III found in the later model Camaros, Firebirds and Corvettes.. They are far superior to the older style injectors and can be found in 22lb flow rates for stock applications.. As for a cam, Like Ken said look for duration and do not worry to much about lift..

[TGed]

Right now the cheapest increase of power with minimal effort would probably be 1.6 rockers...  Maybe a CAI if you can keep it on the cheap, injectors and then a tune. 
The most expensive would be Cam, valve job and springs, complete Exhaust upgrade, port work and a bottom end refresh.
Start doing all that, you'll need to look into trans work, suspension mods, and to put icing on the cake, alky or meth injection.

[TGP Nick]

ummm yes they will... All tgps experience valve float @ or around 4800rpm...

Seriously?  How can you prove this?  I'm not saying that I don't believe you, but it is kinda hard to believe this would happen on a stock application, especially at such low RPMs..

[cobracmdr]

It is hard to prove Nick without a fast rate camera or a strobe light running on an engine with an open valve cover.  Or some serious engineering work which I'm not about to do because I know it happens.  Basically every spring has a natural frequency or surge frequency.  When the RPM (RPM divided by 60 will give you the 1/s or Hertz of the engine at a specific RPM then this can be comparted to the Hertz natural frequency of the spring) of the cam lobe lines up or excites the natural frequency of the spring it will effectively resonante and amplify the force imparted on it.  I see it all the time on vibration test of certain military sensor programs I happen to design which have high force compressions springs in them. 

So what happens?  The amount of force put out by the spring is partially reversed and the net force acting on the valve is less.  This causes the valve to lag behind the cam lobe and "float occurs"

Or in other cases the spring just does not have enough force output to respond as fast as the engine is rotating.  Could be either case.

Are these engines top end monsters?  By no means.  Is there more power to have and better throttle response?  Yes.  When I put the ls1 springs in my 2.8 it wanted to wind up easier if that makes sense.  The engine felt tighter and more responsive.  It was a worth while mod. 

1.6 rockers will open the valve more, this will not make a big difference but it is easy if you are doing an LIM gasket at the same time.  It is practically free so might as well right?

Really, if you don't have a chip in that thing get one.   My tgp is relatively stock engine wise (other than the cam) and with increasing the boost and tweaking my topgun 160 chip I think I have a pretty solid performer.  Certainly plenty of power for a daily driver/cruiser.  Don't expect to go out there and beat a turbo gutted civic or a STI.  I ran mid 14's and had a 2.8 v6 which at the end was capable of high 13's but it takes a lot of time and effort to get there.  That and the car was down a lot!

[Dark Ride]

The Crane H260 cam seems to be the cam of choice from what I hear, good gain in performance but still idles and drives as it should.
Guys check out this thread: 
http://www.w-body.com/forum/index.php?topic=39094.0
Gutless used LS6 springs, but I don't think he used those rocker studs

[cobracmdr]

The Crane H260 cam seems to be the cam of choice from what I hear, good gain in performance but still idles and drives as it should.
Guys check out this thread: 
http://www.w-body.com/forum/index.php?topic=39094.0
Gutless used LS6 springs, but I don't think he used those rocker studs

Ok guys you can leave the stock springs in there with an aftermarket cam.  But with an aftermarket cam you are only going to make a problem from the factory worse.  Same if you don't get the valve force correct.  Sure it will "work" but so does the stock cam so why don't you just leave it alone then.  These motors were not designed for high reving high HP.  They are for grocery getters which don't usually see above 4800 rpm.  As much as I love the TGP it was an afterthought and was modified to do what it does, it was never intended to do what we do to them in the DESIGN phase of the engine.  That is reality.

[killinprixs]

+ 1 Ken

[flybynite]

Seriously?  How can you prove this?  I'm not saying that I don't believe you, but it is kinda hard to believe this would happen on a stock application, especially at such low RPMs..

I can prove it through countless datalogs of TGPs I have previously tuned. The reason this is hard for you to believe is the lack of experience you have in the auto world..   ;)   I have been turning wrenches for 15 + years and I bought my first TGP in 1996.. How old were you in 1996??  :icon_rolleyes:  Also 4800 is not considered low rpms.. Just pull your front valve cover and rev the engine to 4800 and you will see what I mean. Nick, I am not trying to bash you but you have a long way to go before you are building 400+hp engines and school is only going to teach you so much, You will need hands on experience and many years in the field before you can fully understand the physics of this matter...

[TGP Nick]

I come from across the pond- in the motorcycle industry.  I know very well what valve float is, and have experienced it, albeit at a much, much higher RPM. I was curious to how you found there was valve float is all.  I have floated the valves on different bikes before, and you can feel it when it happened, and sometimes it may make a high pitched screech.

Don't bash me before you know me, because I do know a lot about engines, just not car engines specifically.  I also have been turning wrenches for many years and currently in school to be a mc technician..

Like I said, I was just curious to how you found the valves floating.

[RICHTGP]

Ok! So from the many replies I think I have it. Crane H260 cam, 1.6 stamped steel rockers, chip, 160 thermostat, and bosch 3 or ford yellow top injectors, and LS1 springs and seats. Thanks for everyone's input. Anyone have any of these parts to sell or know where I can purchase the m used at a good price?
Thanks so much for everones input and Happy New Year to all!!!!!!!!!! :icon_biggrin:

[mfewtrail]

"sprayitracing" on ebay has the cheapest price on brand new Ford yellow/orange top injectors. They're rated at 19lb's, but actually flow right at 22lb/hr(I had some flow tested back in 2006).

http://cgi.ebay.com/ebaymotors/Set-of-6-19lb-19-lb-Ford-Fuel-Injectors-NEW_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a0Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem370132252795QQitemZ370132252795QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

[TGed]

Ok! So from the many replies I think I have it. Crane H260 cam, 1.6 stamped steel rockers, chip, 160 thermostat, and bosch 3 or ford yellow top injectors, and LS1 springs and seats. Thanks for everyone's input. Anyone have any of these parts to sell or know where I can purchase the m used at a good price?
Thanks so much for everones input and Happy New Year to all!!!!!!!!!! :icon_biggrin:
[/quote

I still have access to those rockers.

[mfewtrail]

I still have access to those rockers.

Do you have the guideplates from a 1.6 ratio car like he needs as well?