Pwebbz28

iTrader: (31)

I got my L-92 motor all done and we put it on the engine dyno. Make a few heat cycle pulls then get ready to rev it. On the power pull the thing is making great power until it starts floating valves at 7300 RPM. This is with TITANIUM valves and springs that are far beyond a comp 921 spring. this thing should pull to almost 8k no problem. We check lift at the valve and its .030 more than what the cam card says!! We KNOW the cam is good so we start looking at the rocker geometry and find out that its all jacked up. Its so far off the pushrod is moving about 3/8 of an inch toward the intake during the arc! I don't know much about it but the guys at the shop told me that when the rocker starts its almost at a 2:1 ratio and at the end its about 1.5.We call T&D and they say there is nothing wrong with their rocker its our cam and spring. How in the hell can a cam and spring mess with rocker geometry? T&D is saying they will not take a return on the rocker.To make it even worse T&D claims that they know the rocker is fine cause Judson @ S.A.M. is using these same rockers at close to 10k RPM. Little did they know 2 of the guys working at the shop went to S.A.M. and know for a fact he is using Jesel J2K stuff. I am hoping they will fix this problem and soon!. If not im going after some Jesel parts!!

Johny GTO

what is the deal with some of these aftermarket companies?? Customer service like this is unbelievable!!!

If you are right and it is their part that is messed up, i hope you shove their rockers up their ***.

LS1crazy01

iTrader: (14)

Sorry dude that sucks. Good luck man.

Old SStroker

T&D provides detailed instructions for installation height and pushrod length selection. Setup often involves machining or shims. It is not just a bolt on job. If the rocker geometry is "all jacked up", the chances are VERY good that the installation was not done properly.

Assuming the correct parts were used for the L92 head, I would go over the setup/installation step by step with the person who did the work. How many T&D systems have "the guys at the shop" installed previously?

Who designed your valvetrain? Everything needs to be working together to fling big valves (even Ti ones) around at 7000+. It's not just valve mass and spring load. There is way more to it, including the cam lobes, pushrods, spring mass, retainer mass and the correct seated and open loads as well as the correct clearance to coil bind as specified by the valvetrain designer.

I have seen properly designed valvetrains work in one application and absolutely not work in an identical application when they were improperly installed. In virtually every case, the person with the problem blamed the parts (or the parts supplier).

IMO, your engine guys need to recheck the install per the instructions. Just curious: did they purchase the pushrods before they started the install or after?

My educated guess is that the rocker system is not the problem IF it is installed properly.

Jon

MeentSS02

iTrader: (11)

I'm with Mr. SStroker on this one...how in the hell did you or your builder not check the geometry before you put it on a dyno?

And of course they won't accept the part back...it's already been used. What the hell are they supposed to do with it? Put it in a pie, bake it, and eat it?

1997bird

iTrader: (2)

I've never had a problem when talking to customer service @ T&D. They were very helpfull and polite when we were discussing a few issues. It ended up that I missed a step in the install, so I would listen to Old SStroker and go back through the setup per the instructions.

Pwebbz28

iTrader: (31)

I would hope that a shop that builds nascar and prostock motors as well as some record setting diesels knows how to properly set up a valvetrain. The rocker IS made wrong. Why else would it have so much lift? Fulcrum is in the wrong spot. They said they made it to fit under a stock cover. Im not worried about stock covers when i am paying 1500+ for shaft rockers.

needadvice

Have 2 different, independant shops verify that T&D screwed up, and that is was not your people that installed it. Then call T&D back with the evidence.

They'll fix it in that case.

Although I hate when shops say, "oh, this guy is using our stuff and he never had a problem." How gay is that

ChucksZ06

iTrader: (9)

So this great shop you talk about did not check the lift at the valve with the rockers in question? That is not a good engine builder if that is true. You never assume anything when building engines...cause you will get caught like your guys did and then you will have to blame a great company like TD.

Pwebbz28

iTrader: (31)

This is the first time they have ever used T&D. They have always used DRE with stellar results. I suppose they took it for granted that T&D would not make a mistake with their rocker. This is the first set to be made in the contry by anyone. The contact point between the rocker and the pushrod needs to be higher i was told.

Even if the shop IS to blame you dont tell them our product is fine, you made the mistake. They have finally decided to take a look at the rocker and fix it after talking to the shop. Wich is what they should have done in the first place. How many rockers have you had custom ordered/made?

racer7088

The newer LSx style T and D rockers I have seen are absolutely horrible for any kind of big lift (over .700) or longer valves at all. I have gone over this many times. The pushrod cup on these newer T and D LSx rockers was relocated down almost .350 or so and inward as well so that the pushrod cup arc is very screwed up and it only gets worse with bigger lift. If you have say .200 more lift than normal or what they are designed for and you drop the stands the amount you would need to to not overarc the valve side of the rocker to fix the geometry you will really start seeing issues with the pushrod side!

On the last ones (we don't use them anymore) we did for a big NA engine the pushrod cup was almost hitting the stands with the cam on the base circle and then as it opened the pushrod cup arc was so crazy the pushrod would hit into the heads on the intake side of the pushrod hole so the hole would have to be slotted up like an additional .125 or more larger because of the ridiculous pushrod side sweep due to the screwed up pushrod cup arc. I even made a small movie showing the crazy pushrod movement which was on Youtube for a while but is now long gone. They told us since they were custom they would not fix them. The first set we used were the older design which worked great and had the older original T and D pushrod up location and rocker design and did not do this.

The older T and D rockers for LS1 were not that bad at all but the newer ones were redesigned to try and make them "fit better" under the stock covers which is a problem on the average guy using aftermarket rockers and trying to make the valve covers fit without spacers. Unfortunately this is also the result of not having experiance in that area as I have had that same deal and even had like three threads about it over 3 years ago and told people about it numerous times and yet here it is again. We did have some of these newer design deals at SAM one time and I had told Judson about them and after he saw what was up they were also changed over to Jesels which worked fine. That was on a One-Lap deal for a customer.

Bryan Broaddus

Shaft rockers are not a bolt on deal.

To optimize the rocker ratio, contact patch/sweep on the valve tip you must know the valve length, installed height, pedistal height and cam lift. If you buy off the shelf parts you will not get what you need.

On my modified LS7 heads I sent them to T&D with the valves and the camshaft numbers I am running and then they made me a set of rockers. Even when they have everything it requires some measuring and mock up on the engine builders part. If you want the engine to run well and not have valve trian failures you must measure every part of the valve train to insure it is properly aligned and functioning correctly. I spend more time on the valve train then any other area on the engine.

I have used T&D and Jesel rockers from 1.5 to 2.0 ratio and all of them require intense attention to the setup.

LSPerformance

iTrader: (23)

Engine parts may be at fault sometimes, but it is ALWAYS up to the engine builder to catch something like this. If something seems wrong, the manufacturer needs to be called to see what can be worked out.

nine-eight

iTrader: (7)

agreed. any shop that does not do something as simple as checking the rocker/pushrod valvetrain geometry on a custom motor by checking the swipe pattern on the valve stem head is the equivalent to billybob johnson reworking his own nascar motor in his kitchen sink with a fork and a blowtorch.


imho, it would not be uncommon for any aftermarket high end rocker/milled custom cast head combo to have the rockers themshelves shimmed along with custom length pushrods to compensate for the heavy valvetrain geometry changes (compared to stock) along with any heavy milling done to the heads

from what people have posted(koenig above), I would think that the rockers themselves may have some faults, but i agree entirely with the above that if something is that out of tune as far as geometry, the engine builder should have at least raised some concern over it. when the engine is cycled by hand, does the swipe pattern on the valvestem head stay centered? lots of people order high dollar rocker setups and just bolt em on and go, expecting that for the cost they should run just as they are and be "correct" when in truth exotic motor components are far from that. they offer fantastic performance, but many times they require some handwork to get the correct geometry/clearences/etc. etc.

adjustable-height pushrods are about 12 bucks apiece. you adjust them until they give you a correct valvetrain geometry (lsx's geometry is set by the pushrod length) and measure the adjusted length with a caliper to order your pushrods AFTER the motor is set up on a non-adjustable valvetrain geometry motor like the 3rd gen + chevys, unless the parts supplier has extensive experience with the exact deck height/heads(in milled form)/ gasket thickness/pushrod/rocker/spring/valve combination and can vouch for the system fitting properly with a return policy on the pushrods.

JBM

iTrader: (15)

L-92 or traditional ls1 style heads? I've got T&Ds made for ETP heads, and my builder said they set up fine. Haven't fired it yet though.

Yeahdoug

I'm also wondering how they didn't catch this before, since they would have had to go through all this while setting them up correctly. Not saying the parts are not faulty, but you might have been able to return them if you had caught it before running them.

Beaflag VonRathburg

iTrader: (176)

racer7088

The problem that they are having has nothing to do with checking the swipe pattern on the valve stem head. The pushrod side is what is screwed up on it.

If you put more lift in it and then fix the valve side for sweep the pushrod starts to actually get even worse and it's bad already as-is.

I was told by people there that this was simply the new design redone for clearance and that you just couldn't run a lot of lift on it.

I should say that I have no idea what they are doing but we had something in the .8XX range and it wasn't even workable.

The first set of rockers I used were a different design and worked great though but had a radically different pushrod cup location that was near tangent to the arc at midlift when the valve side was also tangent to the valve at midlift.

We only changed our rockers to get more offset to run bigger pushrods and this second send also had "incorporated" the new crazy FUBAR pushrod cup locations. They said that they wouldn't fix them so I have never used their stuff again.

There other more well developed stuff of course works fine and I have never had any problems whatsoever with any of that stuff just their newer hoopty model LS1 deals.

racer7088

Doug we never ever ran them and we couldn't return them! They told me that they knew they were like this now and that they were redesigned with more clearance to the back of the head and valve cover rail and that this was workable at lower lifts. That was about 3 years ago.

We use Jesel now on LSx stuff and of course still need valve cover spacers etc. but we have no other problems like these geometry concerns. When you under or over arc the pushrod side you can generate some crazy problems as you know. I think I still have our old ones as they are not able to be used on anything with over .550 lift.

racer7088

Yep that's why we didn't use them at any of the places I have been after seeing the craziness first hand.

T and D's other or newer rockers like the ETP 11 degree or C5R are probably traditionally constructed and should work fine like all their other stuff.

The ones I had the issues with and have seen other have problems with are the normal LS1 15 degree head deals although the L92 has a different intake rocker with offset.

I do not know if these are still the same design as the ones we had as far as these L92 versions but afer hearing ""Its so far off the pushrod is moving about 3/8 of an inch toward the intake during the arc!"" it sounds awfully familiar.