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Bent Pushrods-Trickflow 240 Heads

The exhaust valve lift would be 0.564 thousand's with that cam and 1.6 ratio rockers.
Maybe not enough spring pressure to control the extra mass of the hydraulic roller lifter?????
 
He is removing the heads again at some point. I would think if that happened there should be marks on the piston heads?

P2V - piston to valve?

Thanks for the help
Yep! Piston to valve.
If you have a bore scope you might see a mark on the piston and/or valve. There can be contact that's hard to see with new pistons.
I don't see your lift being an issue...those heads are good to .680... And the cam isn't aggressive so I'm rethinking if its p2v. Just seems unlikely now having looked at cam spec.
I think @PRHeads called it .. the rods were too small. I'm very curious to see what the culprit is. Let us know what you find
 
The builder said he never should have used the rods I gave him but I did have motor running a few times after I got it back from another builder. I did rev it much cause it was new. Because of the head gasket issue I removed heads and the pistons were fine thankfully.
I wasn’t going to give the motor back to a builder who didn’t deck the block knowing the aluminum heads should use the cometic gaskets and they required a smooth deck surface. I had other issues too with the first builder. It’s drama.
The new is going to double check everything and is pretty confident that the pushrods weren’t strong enough. They were aftermarket crane? Isky? Can’t remember but they were straight when I removed the heads.
I’m thinking the pushrods too but he is going to grind clearance in the heads and block too make no rubbing.
I was just thinking why this wouldn’t come up before since Trickflow sells a top end kit pushing 600 hp with no mention of pushrods and no pushrods included in the top end kit.

Maybe because it was decked and heads surfaced? The felpro gasket left impressions in the head so I had him surface them for the new cometic gaskets. Tried to cover all bases. I will let everyone know
 
You need custom pushrods with pretty much any performance adjustable rocker engine builds. Normally just call Smith brohs and they'll take the info and build what you need.
 
Yes I did tell the builder about Smith Bros. He will use a measuring device to get the proper length and order them making sure of the proper ends.

If this is a weak pushrod issue I find it hard to believe it hasn't come up before.

Thanks for the advice.
 

I wasn’t going to give the motor back to a builder who didn’t deck the block knowing the aluminum heads should use the cometic gaskets and they required a smooth deck surface. I had other issues too with the first builder. It’s drama.

I run regular fel-pro’s with aluminum heads.

Is that something special for Trick Flow’s?
 
I fail to see any advantage with the extremely overpriced cometics other than more thickness choices. The Felpros are far more forgiving regarding how smooth the sufaces are. I think the Felpros tend to seal up the coolant passages better also. Wonder if you can get the blue composit Felpros for the Gen 3 Hemi which is not so great with the MLS gaskets in my experience??? Probably not unfortunately. Hate the torque + turn BS throw away bolts also.
 
I had problems with the felpro but I have heard from people they have not. The MLS gasket is supposed to be a better choice because of dissimilar materials “moving”.
I know of very popular users such as Just Mopar Joe using them instead of felpro on his builds and Trickflow now sells them with their kits. The heads studs also convinced me due to their fine threads on the outside which will hold better.
I’m not trying to convince anyone. Just pointing out my own experience. Also Trickflow did mention retorque the head bolts in the original directions using felpro. When I looked up the heads again later I noticed they changed to cometic in their kits. Maybe they had a change in their minds.
 
The exhaust valve lift would be 0.564 thousand's with that cam and 1.6 ratio rockers.
Maybe not enough spring pressure to control the extra mass of the hydraulic roller lifter?????
As mentioned multiple reasons for bending pushrods, retainer to top of valve guide, rockers hitting springs a max lift, piston to valve, pushrods rubbing head. 5/16 pushrods are not really big enough for what sounds like a pretty good performance engine. I did have to relieve the rocker arm stands on my trick flow 270 heads to clear the rockers.

That head should have guide clearance to run .700 lift But I have seen a lot of issues with people short cutting assembly mockup and checking clearances. Light springs are OK but I like using clay. Clay will show you the clearance across a valve notch in a piston, where a light spring just means it rolls over cold. And if it bent the pushrod, even a 5/16 one are the valves bent? If it where my engine top end would come apart and a more careful clearance check is needed. If using the hydraulic lifter in clearance checking did the plunger compress, and then when it got oil in it reduce your clearances? I have seen valves hang in a guide, bend pushrods and kick out lifters.
 
As mentioned multiple reasons for bending pushrods, retainer to top of valve guide, rockers hitting springs a max lift, piston to valve, pushrods rubbing head. 5/16 pushrods are not really big enough for what sounds like a pretty good performance engine. I did have to relieve the rocker arm stands on my trick flow 270 heads to clear the rockers.

That head should have guide clearance to run .700 lift But I have seen a lot of issues with people short cutting assembly mockup and checking clearances. Light springs are OK but I like using clay. Clay will show you the clearance across a valve notch in a piston, where a light spring just means it rolls over cold. And if it bent the pushrod, even a 5/16 one are the valves bent? If it where my engine top end would come apart and a more careful clearance check is needed. If using the hydraulic lifter in clearance checking did the plunger compress, and then when it got oil in it reduce your clearances? I have seen valves hang in a guide, bend pushrods and kick out lifters.

Yeah the heads are coming off for sure. When I touch base I will mention those things.
I should know within a couple weeks?
The pushrods order needs to arrive and I’m sure he has other work in between.

Thanks
 
The springs are new and supported to be capable of cams .600 lift. Coil bind and pressure will be on the check list.

I will call Howard’s Cam though and see what spring pressure is recommended for that cam.

Thanks
 
So wait a minute, your “engine builder” installed a Hyd roller cam & trick flow heads with heartland and sharp 1.6s and never actually measured for proper push rod length!!! To be on the safe side I would have the heads checked to insure none of the valves are bent. I have heard of instances (big chev) were valves hit the pisstons and left almost invisible marks.
 
So wait a minute, your “engine builder” installed a Hyd roller cam & trick flow heads with heartland and sharp 1.6s and never actually measured for proper push rod length!!! To be on the safe side I would have the heads checked to insure none of the valves are bent. I have heard of instances (big chev) were valves hit the pisstons and left almost invisible marks.
I missed the hyd roller part.

Bad things can happen on big block mopars with hyd rollers. DAMHIK. What I learned is that they are very heavy and do not like rpm! I ran into trouble with mine at 6000 rpm (it was still pulling like crazy at 6000 rpm). My valve train went crazy around 6000 rpm (valve float - which can bend push rods, but did not in my case). I found out a few things about running hyd rollers in mopar big blocks:
- The valve spring pressure is absolutely critical, and it needs to be a balance, meaning can't be too much or too little. My cam was also a kit, but at the end of the day we determined that the springs were not stout enough.
- I learned that in order to pump these lifters up at rpm, you should not use any oil heavier than 10W-30 (a good experienced mopar engine builder taught me that).
- Are you sure you did not exceed 5500 rpm? In the future if I use another hyd roller I will build it so that its all done at 5500 rpm.

Others may have different experience and or opinions.

At the end of the day with these lifters, it was street car with very few miles (under 50) and 3 runs at the track. At that point I pulled the motor and went through it to figure out what happened. It is sitting now as a good spare. I put the original motor back in the car.
 
Buddy had bent some pushrods. We checked everything and found no problems with interference, but the pushrods were the wrong length, and I think a thinner wall thickness, maybe 0.060"?
Measured for correct length and got the 0.083" wall pushrods from Smith Brothers (pushrods.net) and no more issues.
This was a flat tappet solid cam around 0.600" lift as I recall.
 
I missed the hyd roller part.

Bad things can happen on big block mopars with hyd rollers. DAMHIK. What I learned is that they are very heavy and do not like rpm! I ran into trouble with mine at 6000 rpm (it was still pulling like crazy at 6000 rpm). My valve train went crazy around 6000 rpm (valve float - which can bend push rods, but did not in my case). I found out a few things about running hyd rollers in mopar big blocks:
- The valve spring pressure is absolutely critical, and it needs to be a balance, meaning can't be too much or too little. My cam was also a kit, but at the end of the day we determined that the springs were not stout enough.
- I learned that in order to pump these lifters up at rpm, you should not use any oil heavier than 10W-30 (a good experienced mopar engine builder taught me that).
- Are you sure you did not exceed 5500 rpm? In the future if I use another hyd roller I will build it so that its all done at 5500 rpm.

Others may have different experience and or opinions.

At the end of the day with these lifters, it was street car with very few miles (under 50) and 3 runs at the track. At that point I pulled the motor and went through it to figure out what happened. It is sitting now as a good spare. I put the original motor back in the car.
I will mention those points. Thank you

The springs are supposed to handle.600 lift cams. I will call the cam manufacturer tomorrow for the spring pressure specs.

The builder told me that the motor didn’t reach 6000.

I will mention the oil too.

Did you use a high pressure/volume oil pump?
 
Buddy had bent some pushrods. We checked everything and found no problems with interference, but the pushrods were the wrong length, and I think a thinner wall thickness, maybe 0.060"?
Measured for correct length and got the 0.083" wall pushrods from Smith Brothers (pushrods.net) and no more issues.
This was a flat tappet solid cam around 0.600" lift as I recall.
Thanks
That’s the plan with a thorough check on everything else.

I wasn’t aware about the oil viscosity issue.

Did you use a high volume/pressure oil pump?

It seems the valve this roller valve train demands more oil flow. I always had 70 psi at start up with new engines but this engine I was told with a regular pump was 45-50? It kept 45 during runs and maintained temp during runs.
 
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