TrickFlow 190 Issue

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19DUSTER73

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I have a set here that I purchased in April 2019. After a couple years of scrounging parts I am finally able to use them or so I thought... with all 10 head studs in the block the heads will not sit on the dowels as they should. So I pulled all but the corner studs, set the head on the block and it sits as it should. I start putting studs in 1 by 1 looking for an issue. The long stud between cylinders 5 and 7 will not thread in as it should. I checked both heads on both sides. The issue moves to between cylinders 2 and 4 on the other side. Looks to be the hole location in the head. Best I can tell the hole is too high (biased intake side). I have some more checking to do to verify but at this point it looks like the hole is in the wrong location. I'm waiting to hear back from Trickflow. The fix is as simple as plunging an end mill in there to slightly slot the hole I think. I assume there's plenty of material there but waiting to hear back to see what they want to do.
 
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I have experienced this with Trick Flow heads before. It is likely not the head's fault. To have room to CNC the ports as large and straight as possible, Trick Flow machines the bolt holes on the small side, but plenty large enough for the fastener. The problem is that the factory bolt holes in the block weren't the most accurate, but the extra room in the factory head bolt holes allowed the heads to fit just fine anyway. Also, the factory bolts have a somewhat smaller shank diameter than a stud, so that gives even more clearance.

You can open the holes slightly, but be careful you don't break through into the intake port. I would put the gasket on the deck and take a close look at the bolt hole locations in the block. It should be obvious if there are holes that are shifted.
 
The gasket goes on without issue. I had the same thought at first about the bolts. It's the same on each head. I'll wait to hear back from them. I had the same fear of breaking through.
I have experienced this with Trick Flow heads before. It is likely not the head's fault. To have room to CNC the ports as large and straight as possible, Trick Flow machines the bolt holes on the small side, but plenty large enough for the fastener. The problem is that the factory bolt holes in the block weren't the most accurate, but the extra room in the factory head bolt holes allowed the heads to fit just fine anyway. Also, the factory bolts have a somewhat smaller shank diameter than a stud, so that gives even more clearance.

You can open the holes slightly, but be careful you don't break through into the intake port. I would put the gasket on the deck and take a close look at the bolt hole locations in the block. It should be obvious if there are holes that are shifted.
 
The gasket goes on without issue. I had the same thought at first about the bolts. It's the same on each head. I'll wait to hear back from them. I had the same fear of breaking through.
Yes, the gasket will go on without issue. The holes are extra large. I'm not saying there couldn't be an issue with the head, but my experience was that the holes were shifted in the block. Being a TF dealer, I do quite a few builds with them, and haven't had a head with improperly located holes yet.

The engine I had a problem with was so bad I had to ream the holes slightly larger, and turn down the dowels so the head could shift a little to get the bolts in. Then I had to leave them loose and bolt the intake to the heads, before torquing the head bolts, so everything would align properly. It was all poor machining from Chrysler. But, like I said, it might be the heads, but I'm betting it's the block.
 
Yes, the gasket will go on without issue. The holes are extra large. I'm not saying there couldn't be an issue with the head, but my experience was that the holes were shifted in the block. Being a TF dealer, I do quite a few builds with them, and haven't had a head with improperly located holes yet.

The engine I had a problem with was so bad I had to ream the holes slightly larger, and turn down the dowels so the head could shift a little to get the bolts in. Then I had to leave them loose and bolt the intake to the heads, before torquing the head bolts, so everything would align properly. It was all poor machining from Chrysler. But, like I said, it might be the heads, but I'm betting it's the block.
I'll look everything over in the next day or so. I was kinda frustrated the other night. The holes in these Cometics are pretty tight to the studs. The block was in my first thoughts as well. Then I tried both heads on both sides and the problem moved as if the head was the issue. But like I said I got sort of frustrated and just quit for the night. I'll regroup and check things over again.
 
I'll look everything over in the next day or so. I was kinda frustrated the other night. The holes in these Cometics are pretty tight to the studs. The block was in my first thoughts as well. Then I tried both heads on both sides and the problem moved as if the head was the issue. But like I said I got sort of frustrated and just quit for the night. I'll regroup and check things over again.
Hey, the Trick Flow people are human too, and can make mistakes, so the heads could have a problem I haven't seen. I just wanted to save you some grief exchanging out heads if that wasn't the problem. Let us know what you find.
 
Hey, the Trick Flow people are human too, and can make mistakes, so the heads could have a problem I haven't seen. I just wanted to save you some grief exchanging out heads if that wasn't the problem. Let us know what you find.
Will do. I appreciate and value your input.
 
Will do. I appreciate and value your input.
Just an afterthought. Lay the gasket on the heads too, using dowels for alignment, and see how it looks. Between the block and the heads, the gasket should make it obvious which one is "off".
 
Just an afterthought. Lay the gasket on the heads too, using dowels for alignment, and see how it looks. Between the block and the heads, the gasket should make it obvious which one is "off".
Good idea. I'll check it out when I get home tonight.
 
Just an afterthought. Lay the gasket on the heads too, using dowels for alignment, and see how it looks. Between the block and the heads, the gasket should make it obvious which one is "off".
The heads passed the gasket test. Looks like it's the block. But outta time tonight. I noticed something though. I think the bolt hole in the block may have a little angle to it. When threading in the problem stud it doesn't seem to be an issue until maybe 1/4-3/8" below the fine threads. I can see where it touches and rubs the head as it's threaded in. There's also an increas in resistance while threading it in. Now I'm concerned about angles and clamping forces. Time to replace the batteries and grid heater relay in my pickup.. Thanks B3RE!

Had to edit that lol. Busy trying to update this post and wrangle the kiddos. Dang near forget what I'm doing half the time lol
 
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hard to imagine the head bolts are off from each other as they are all drilled on the same 10 drill fixture.
 
hard to imagine the head bolts are off from each other as they are all drilled on the same 10 drill fixture.
The stud...
If he compared the two, stock head bolt vs stud.. there lies the cause. Studs have the threads machined out...so the shank is as big as the thread while a head bolt is shouldered but smaller in diameter above the threads.
Solution.....lathe/turn down the stud OR drill the head bolt hole on each .020 larger aka .040 larger bit.
 
The stud...
If he compared the two, stock head bolt vs stud.. there lies the cause.
Solution.....lathe/turn down the stud OR drill the head bolt hole on each .020 larger aka .040 larger bit.
I couldn't leave it alone so I went back out to the shop. Took a spare stud I had and turned it down roughly .012". I say roughly because my lathe at home is a Milwaukee drill with the trigger zip tied on and a Milwaukee grinder with a flap disc. Hillbilly I know but it gave me an idea of what needed to happen before removing material from the head. I stopped at a couple unknown points and ran the stud in through the head and into the block before arriving at .012" of material removed. I was able to freely take the head on and off the block with all 10 studs in place. If I were to decide to turn the stud I'd take it to work and do it right. I'll probably open the hole a little instead though.
 
I couldn't leave it alone so I went back out to the shop. Took a spare stud I had and turned it down roughly .012". I say roughly because my lathe at home is a Milwaukee drill with the trigger zip tied on and a Milwaukee grinder with a flap disc. Hillbilly I know but it gave me an idea of what needed to happen before removing material from the head. I stopped at a couple unknown points and ran the stud in through the head and into the block before arriving at .012" of material removed. I was able to freely take the head on and off the block with all 10 studs in place. If I were to decide to turn the stud I'd take it to work and do it right. I'll probably open the hole a little instead though.
Good work.
Make sure to leave enough clearance for expansion.
:thumbsup:
 
Wouldn't change the stud diameter by machining/grinding because you change the tq value & also disturb the grain structure.
I have only fitted one pair of TF heads & I was impressed with the accuracy. Many aftermarket heads require 'help' to fit over the dowels. These didn't.
 
That was my point. I don't know & what criteria would one use to 'select' a new tq value to tq the bolt.
 
The stud...
If he compared the two, stock head bolt vs stud.. there lies the cause. Studs have the threads machined out...so the shank is as big as the thread while a head bolt is shouldered but smaller in diameter above the threads.
Solution.....lathe/turn down the stud OR drill the head bolt hole on each .020 larger aka .040 larger bit.
I'd not turn the stud down, you'll surely lose strength. Clearance the head or use a good bolt. I dont follow the design comparison...they look similiar to me as both types are rolled threads from the same stock. The stud have a larger OD? Hard to tell in these 2 pics.
s-l500.jpg

AR144-4202.jpg
 
I'll refer you guys back to the oil pump clearance in regards to studs in the rear main on a small block and the usage of one regular main bolt and one stud. I've done it to know as well.
Turning that already stronger than stock bolt is not going to be an issue or weaken the stud in such way to give any problem or indication it was ever turned. To each his own.
 
hope all works out for you , my trickflow heads should be on the engine ready for a dyno run soon i hope . if things don't line up properly back to the edelcrap eads
 
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