XxNaSDaQxX

iTrader: (5)

Thanks Pred I thought I was the only one. I’ve been doing the numbers and this is why I’ve been asking questions for a buddy. By no means KrisXpc am I per say, "dissing" you. However all the numbers dont match. Hence why I asked on the pushrods and gasket size. We are using an Ls6 heads (stage I), Ms4 cam 100+3, PRC Double springs, Tit retainers, etc. However from others Ive read, none of which TSP actually responses to btw. Ran several searches. But those that have done it milled the heads, thicker gaskets, fly cut pistons, or etc. / similar. That’s why I was asking which way you did this. Im in total agreement with Pred that it will be kissing the piston and on the .650 lift it will break the valves. It will work but for how long is the real question.

Love the car, cam, and sound. Great work none the less and definitely good luck to ya. Great vids and I cant wait to see more.

-J

dazman

i begged tsp to let me get the 110 but they would not let me (advised against it).... LOL... said it would not work on my setup

ms4
prc stage 1 ls6

93camaro_zzz

iTrader: (13)

If it is dangerous, and not to be used with stock heads, then why did TSP throw it in an LSx with factory heads, and still has many customers with "cam only". If it was so that it WILL touch the pistons, then TSP would post it on there site, and I dont think they are one to have bad customer service from all that ive heard, and delt with them personally. JMO though.

Still soundin bad *** Kris.

PREDATOR-Z

We are talking about a 110 LSA

111,112,113,114 all fit with enough clearance.

Now 110 is a different story, but perhaps you can't even picture how tight is clearance.
Safe clearance is .080 inch/intake and .100 inch/exhaust. take a ruler and visualise that distance. Now less than that becomes dangerous and a 110 is much less than that.
Why would I advise otherwise? I can't care less, but I like to share my knowledge with my LSx community (as long as they are not my competition) .

93camaro_zzz

iTrader: (13)

So your saying, that the LSA makes his valves closer to his pistons. It has nothing to do with it. LSA is just more overlap when compared with duration. It has to do with total valve lift (Cam lift + rocker ratio). Please explain your theory.

XxNaSDaQxX

iTrader: (5)

In short:
Cam LSA can change piston to valve clearance due to the overlap. When you change the valve events (timing), the clearances will change and should be checked.

LSA for a performance ground cam is typically between 106-114 degrees. Sometimes even less than 106 is ground for stroker engines. When duration is increased and LSA is constant, the valve overlap is increased. When overlap is increased, vacuum is lower, cylinder pressure is reduced and reversion is increased. These are all undesirable traits for low end and midrange torque. You need cylinder pressure and vacuum for low end torque. Unfortunately, we cant have our cake and eat it too. For high rpm power, duration must be increased but we cant widen the LSA or the valve events will be occurring during wrong points in the piston’s travel. As piston speed is increased, the time that the cylinder can adequately fill and evacuate is drastically reduced. To compensate for this, we must increase the time that the intake valve is open to admit more fuel/air mixture, and the exhaust valve must be open longer for exhaust gas evacuation. The only way to do this, is to increase duration and lift. We are limited to the amount of lift because the lobe flanks/ramps have to spread out or the lifter will not ride up and down the lobe properly. Roller lifters help because they will transverse up a much sharper lobe flank than a flat tappet lifter, but there’s still a limit for them as well. A very aggressive profile is also hard on the entire valve train and camshaft.

I can break it down from LSA to the LCA and explain what overlapping is doing if you like.

PREDATOR-Z

93maro-zzz,
No offence man but search my forum name in this section, I know what I'm talking about.
Lift has F**k all to do with clearance. (Unless you are in stratospheric lifts).
Max lift occurs when piston is close to BDC.(Bottom Dead Center)
Clearance issues start occuring around 10* +/- from TDC. (Top Dead Center).

That is why when you measure PTV clearance you should start doing so from 10* BTDC to 10* ATDC. That is where contact will occur if there is not enough clearance.

Durations and valve events (VE) are what affect PTV, LSA is just a by product of your VEs and along with ICL (LSA - advance or retard in grind) can be used to tune the VE's for clearance.

PewterZ28

iTrader: (1)

1700 rpm idle? Are you serious?

Bryan @ Speed Inc.

iTrader: (19)

i know... the tach didn't look like it was reading 1700...

also - my G5x3 110lsa in my old car idled FINE at 900-950.

LS1B|RD

couldn't agree with this advice more!!!

Killer_Bluebird

iTrader: (23)

Like it was mentioned before the 111* and the 112* grinds are fine in the P2V department although they are close. The reason TSP don't offer the 110* on the site as an option is because of the clearance issue. They probably don't want people ordering the 110* not knowing they will not fit under their stock heads and have to deal with unhappy custumers with blown motors. Like it was mentioned before you are playing russian roullete with your engine. At idle you will probably be fine but one WOT pass with harder pushrods can be the end you your valvetrain and possibly motor. If I where you I would use stock pushrods so if the you do tag a valve at high rpms you may just endup with a bent pushrod instead of bent valves or worst. But better than that I would recomend claying the engine and getting ready to flycut. Good Luck!

4U2BNVS

iTrader: (2)

you better search thery're site cus the 110 LSA is right on there.

Killer_Bluebird

iTrader: (23)

Not on the pull down on this page: http://texas-speed.com/shop/item.asp?itemid=666

KrisXpc

iTrader: (13)

Thanks for the advice.. I honestly did quite a bit of reading into this cam and this is the first time ive heard anything about the PTV clearance the 110 lsa cam.. Im going to give them a call right now and see what they say.

Even when I spoke to jeremy formato. He mentioned nothing of the PTV clearance..


Thanks for the honest advice...

The Wreckoning

iTrader: (3)

damn that car sounds mean

93camaro_zzz

iTrader: (13)

First, anyone would know that clearance issues would obviously happen at TDC, and not BDC. I don’t think valves are going to have clearance issues when the piston is 3” down the bore. And also, lift does have to do with ptv clearance. If you take a cam with the same LC, LSA, and duration numbers, but one cam has .050 more lift, would that not make the intake ramp steeper? And would this not occur right at the point (10btdc-10atdc) that clearance is important? I agree that ptv clearance does have to do with EVERY measurement on a camshaft. But IMO lift is the most important of them all. And just because I don’t have 8000+ posts on this site, doesn’t mean I have a lot on others, or that I don’t know what I’m talking about.

PREDATOR-Z

You have no clue and you're making an *** out of yourself arguing this point. Read my post again and go read about 4 stroke dynamics.

bshonda

iTrader: (1)

dont be such a dick predator, there are only about 14000 different opinions floating around on the forum about how or how not a cam works. this gets awfully confusing for us novices that are just trying to kick some cobra's *** on the street. i dont really care how long your brain ******* is, you just have me worried about the post you made on my cam selection and its PTV clearance. are you saying that if you stay within the 10* mark BTDC and ATDC that i wont have any problems? and am i understanding correctly that the higher the lift the more aggressive the lobe profile is? so my lower lift, .579, would have a much less aggressive profile than a .600 and hence take longer to open and close because of that? im an idiot, so you dont have to tell me what i already know, just explain in layman's terms what tha hell your talkin about!!!

RobbieTransAm

iTrader: (4)

Sounds sick! I finally got my MS4 started last night on a 111. It holds a steady 900 RPM idle, I was shocked it ran so well.

PREDATOR-Z

Man, so i'm a dick because I explain something.
How much more Lehman can I get by saying that lifts have very, very, very little to do with PTV at the durations we are running. (you can literally say nothing to do)
Look it is simple, at TDC valves are closed (lowest lift point), at or close to BDC, valves are open to their maximum (piston is in the bottom), max lift.
So the danger lies when the piston comes back up close to TDC. If at that time the valve is still opened too much, whack, Mr. piston meets Miss valve.
The time action of the valve opening or closing is dictated by the Durations and the Valve Events of the cam. Valve Events are dictated by Duration, LSA and ICL. Lifts are not involved at all.

Exemple: a 224/224 .563/.563 112+4 LSA (TR224), has the same VEs than 224/224 .581/.581 112+4 (Comp XE-R) and the same VEs as 224/224 .636/.636 112+4 (Comp LSK).

If the TR 224 clears a certain head so will the others even though you can see the lift difference. THEY ALL HAVE THE SAME VEs
Now change the VEs (which means a different LSA/ICL) and at a certain level, you can find yourself with a cam that doesn't fit even with same Durations.

I really can't explain simpler than that.