I use 11/32 on TFS intakes and 3/8ths on exhaust as that all that will fit the bigger heads with the port moved over. We've used larger but we had to modify the heads. The smaller and older heads can run 3/8ths on some depending on rockers.

As always you have to check first. Get 1 3/8ths and then check.

 

yeah would have been nice to hear that from TEA

 

It could be worse! I am using the T&D/Comp shaft rockers on TFS 215's and my 5/16" pushrods are contacting the hole on the side of the intake runner. I was using the 5/16" rods to measure preload and set my wipe pattern and was planning on ordering a set of 11/32" Manton's. I called TEA to see how much meat there was in this area to clearance and found out in some spots it is as thin as .010"! I'm still gonna go with the 11/32" and try to clearance the heads to get minimum clearance. If I bust thru the runner I'm just gonna have bronze bushings pressed in. Good luck with yours Chris!

 

good luck to you too...wow that sounds like fun...You win on the problem scale...keep me updated...

 

We also run 11/32 on all of our TEA/TFS heads.


Zach

 

Yeah I know the newer style T and D rockers for the normal cathedral port LS1 stuff have some bad stuff going on at the pushrod end. The old cathedral port T and D rockers worked great but didn't clear the valve covers so they moved the pushrod pivot and now it is like that. One problem for another.

 

I'm hoping it sounds worse than you meant it to, but the "bad stuff at the pushrod end" statement has me worried. Is this mainly a clearance causing issue or is there something else that should concern me about them? My cousin had a set on a solid roller engine a few years back and they seemed to be a really nice setup. I was not aware that they were redesigned... that sucks.

 

Yes the T and Ds were redesigned solely for pushrod clearance and the pushrods had a ton of movement so much so that on some setups they bind up easily with a 3/8th or even a 11/32 on some heads. You had to slot the pushrod holes in the heads (on stock heads) so the pushrods moving back and forth wouldn't bind up. Haven't used any more for a long time since then and do not know exactly if they ever changed back but the old T and Ds I have right now are very nice but of course you need valve cover spacers on them but the pushrods have a very minimal arc and are done right.

 

He Chris what did you mill you heads to? I have the same 215 tfs heads with a Ms3 cam and figured I couldnt mill them much at all. I'm also using a cometic gasket .040 thickness.

 

my cam is around a ms4...my heads are at 57.5cc...I have flycut using the Lindy tool to a depth of .110...I have right around .090 clearance now running the .040 gasket...

when I got the heads they were at 60-61cc and when I mocked them up using the .040 I had like .005 clearance...then took another .025 off the head to my current cc so that would be -.020 clearance...then add the flycut an you are at .090 todate...

I would think you might just have enough running the stock heads at 64 unmilled if you didn't want to flycut...I would definitely still check...

pm me if you want to rent the tool to flycut..good luck man

 

The push rods are going to flex and swim all over the place no matter what you do and if they touch a little that won't hurt anything as long as they aren't binding, I can't count How many race and hi performance engines I've torn Down and seen aluminum on the push rods with even up to .040!, My Manley guy I talk with says it can actually help transfer vibration from the p-rod fwiw imho

 

I am so happy that I found this thread.

I have been having a breaking up issue at 3600 rpm since I got my engine together a few days ago. I pulled off the valve covers and saw that the pushrods were rubbing the head and side loading the lifters causing binding. I tried calling Thunder Racing 3 times today to sort out the issue but I did not get an answer. I already had the old style T&D shaftmounts and I didnt want to grind on my heads and my valve covers so I returned them for the new style. Now I have this other problem with the new style. I am pretty much over it now. I guess I will rip out the T&D shaftmounts return them to Thunder Racing and replace them with something that actually works without having to modify my heads now that they are already on the car.

If anyone has any suggestions that would not require me to remove the T&D shaftmounts and would not require me to grind the pushrod holes bigger please shed some light on the subject for me. I have the 5/16 pushrods so I guess I need to get the 11/32 ones in a 7.050 length. Anybody know where I can get those next day shipped to me?

 

I don't know and can't know the specifics of your issues but all this stuff has to be mocked up and checked PRIOR to assembly or this will happen at least 85% or more of the time. I am always shocked when stuff really does just "bolt on." Then I really think something must be wrong!

Anotherwords you might also have other issues as well but basically you need to remove the heads and clearance them and then reclean and set the springs back up and put them back on and you should be fine. There's no way to fix it with the engine altogether. We see stuff like that unfortunately every week it seems.

 

I'm messing with mine right now. There are shims on both sides of the intake rocker and it appears that it will allow the rocker to be repositioned. I was trying to get the snap ring off the shaft and do some measuring, but broke the snap ring pliers. Now I'm going to wait till tomorrow to play with it some more. I think moving the rocker arm over will allow the pushrod to clear, but I don't want to move the rocker tip too far off center. I just looked up the valve spacing and it is 1.910" from center to center(in case you want to play with this theory and do some measuring).

 

I had to go take a couple measurements myself or I would not be able to sleep tonight thinking about it. My valve spacing is 1.910" and the T&D rockers center to center is actually 1.875". So moving the rocker over would improve the center spacing. I don't know why they are set up like that.

 

I hear what your saying about mocking it up. I was told that it would work by the company that sold the stuff to me. The 11/32 pushrods in 7.050 length with fix the issue if I can get them next day aired to me. Do you know where I can get them?

I wont be taking the heads off, I will be returning the rockers AGAIN for a refund if it comes down to it. Like I said, I already sent back the old style ones because I didn't want to grind on my head after they were installed.

 

11/32" pushrods are available from Manton. He is quick but all pushrods are made to order so he won't be able to pull them off the shelf and ship them overnight.

 

Chris, Nobody at TEA tried to mislead you. The hole in the head "should" fit a 3/8" pushrod. Unfortunatley the pushrod pinch is a major restriction area of the port and we try to maximize the space in that area to get port window.
And like Eric said, "It depends on what rocker arm you are using". Also 1.8 ratios compound the problem. What rocker are you actually using?

Cliff, Actually the thinnest area is about .040". In your case with your rocker arm the thinnest area is where you need extra clearance. If it was as thin as .010" the porting tool would break through on every port!

 

Mike, I must have misunderstood you on the phone. I know you said in the area of my concern it was 0.040" thick, but thought you said there was an area that was 0.010". I apologize if I misquoted you. I just wanted to inform everyone that it would be best to call and verify thicknesses before cutting on the heads to gain clearance, as there are some thin spots.

BTW I swapped some shims around on the rockers and moved the intake rocker over 0.050". Hopefully I'll have time this evening to see if this will resolve my problem and chime back in.

Thanks to Erik and Mike for the advice!

 

I'd say TEA and TFS have done the most for me personally trying to get it all to work but again it's close so you always have yo check it before hand. I sell 11/32nds Mantons every day but they are made to order and have to be heat treated so it takes 3-5 days or so to get them.