598 turbo motor keeps breaking the head

agreed... but unless I was building a class specific motor, with those kinda spring pressures I would go with the C heads or something else better suited for those types of pressures and designed for a shaft rocker set-up
[/quote]

138,

I would love to have C heads or even Thors. Thors are $10K a set, without valvetrain. So they are out of my price range. C heads are a little more affordable. When I bought these heads, I wasn't real sure about whether C heads had the 18 bolt option. I bought the TFS heads because the 18 bolt option attracted me. On our small block we had "head lifting off the gaskets" problems. So we wanted to take advantage of the block having 18 bolts. I have never seen C heads on a bench in person, so I couldn't even tell you if they have 18 bolts...maybe you know, or Charlie or Lem knows for sure. Either way, when I began buying parts I bought these heads. I built my headers and turbo kit around these heads before I ever even ordered internal parts...so I just kept going with these heads. Plus in the past we have ran a lot of TFS heads (TW, TW-R, High Ports, etc) and have had awesome luck with them. The guys at TFS work closely with TEA, which is where I get all my head work done (Thanks Mike Schmidt!). TFS and TEA are great to deal with. So it was natural for to use TFS....I still believe in these heads. Just need to make it work for my application.

Right now, the only way I would change heads is if I went with Thor's. I wouldn't even mess with C heads at this point. And right now, I just don't have that kind of money and down time...

I would do it differently if I had to do it over though...LOL

Ryan

PS....my heads don't flow much less than a C head on the intake side...and they flow equal or better on the exhaust side!

Thanks again to Mike Schmidt over at TEA...they did an awesome job of getting the #'s I wanted out of these heads!

The TFS 18 bolt deal is a copy of the C460 bolt pattern.

Lem Evans wrote:The TFS 18 bolt deal is a copy of the C460 bolt pattern.

I wish I had known that about 2 years ago...but then I didn't know any of you guys. LOL.

Oh well, I will work with what I got.

And no your A460's will not outflow properly preped C460's.

dfree383 wrote:And no your A460's will not outflow properly preped C460's.

U are entitled to your opinion

chappy89 wrote:

138,

I would love to have C heads or even Thors. Thors are $10K a set, without valvetrain. So they are out of my price range. C heads are a little more affordable. When I bought these heads, I wasn't real sure about whether C heads had the 18 bolt option. I bought the TFS heads because the 18 bolt option attracted me. On our small block we had "head lifting off the gaskets" problems. So we wanted to take advantage of the block having 18 bolts. I have never seen C heads on a bench in person, so I couldn't even tell you if they have 18 bolts...maybe you know, or Charlie or Lem knows for sure. Either way, when I began buying parts I bought these heads. I built my headers and turbo kit around these heads before I ever even ordered internal parts...so I just kept going with these heads. Plus in the past we have ran a lot of TFS heads (TW, TW-R, High Ports, etc) and have had awesome luck with them. The guys at TFS work closely with TEA, which is where I get all my head work done (Thanks Mike Schmidt!). TFS and TEA are great to deal with. So it was natural for to use TFS....I still believe in these heads. Just need to make it work for my application.

Right now, the only way I would change heads is if I went with Thor's. I wouldn't even mess with C heads at this point. And right now, I just don't have that kind of money and down time...

I would do it differently if I had to do it over though...LOL

Ryan

I gotcha... I went with the A's because I found a deal on some new Accu-Fab headers, and a TFS intake and saved liked 900 bucks there ...plus going with A's saved me about 3 grand over going with C's. not to mention that all the parts (valve train) including the heads (maybe with a 2.350 intake) can be used in a toned down factory block street engine later on down the road when and if I decide to go faster with C's or Thors... thats a bad ass engine you have there, you should post a couple pictures. I really like the black valve covers and black braided lines...

138 wrote:


I gotcha... I went with the A's because I found a deal on some new Accu-Fab headers, and a TFS intake and saved liked 900 bucks there ...plus going with A's saved me about 3 grand over going with C's. not to mention that all the parts (valve train) including the heads (maybe with a 2.350 intake) can be used in a toned down factory block street engine later on down the road when and if I decide to go faster with C's or Thors... thats a bad ass engine you have there, you should post a couple pictures. I really like the black valve covers and black braided lines...

Thanks man. We really worked hard on making it look good. LOL. Now if I could just make it run as good as it looks! I really like the TFS stuff. We got amazing #'s on the exhaust side, and on the intake side we did OK. They are definitely not as good as a C or Thor on the intake, but I got the C head beat on the exhaust side. We ended up with a 2.400 intake valve and a 1.88 exhaust valve, so its a tight fit in the chamber. I will get some photos up in a minute.

BOSS 429 wrote:please note i didnt read all the posts

first altho not uncommon to shim (use washers under the stands) theres not enought thread in the head in your case.but the real problem is the rocker them selfs, that style shaft rocker isnt worth crap on an engine like yours, you need a system the at least 2 of the stands bolt to each other, get rid of the ones you have before it kills your engine

If the shim used is smaller than the stand foot print or the pedestal surface, then you have degraded your stability of the stand. Shims may be fine if all the strength is not needed.

The closer the rocker pivot point is to the attachment point the stronger your assembly will be. But what it has to be is what it has to be.

Sounds like he is on the right track now..............

chappy89 wrote:

dfree383 wrote:And no your A460's will not outflow properly preped C460's.

U are entitled to your opinion

If you say so.

IDT-572 wrote:

BOSS 429 wrote:please note i didnt read all the posts

first altho not uncommon to shim (use washers under the stands) theres not enought thread in the head in your case.but the real problem is the rocker them selfs, that style shaft rocker isnt worth crap on an engine like yours, you need a system the at least 2 of the stands bolt to each other, get rid of the ones you have before it kills your engine

If the shim used is smaller than the stand foot print or the pedestal surface, then you have degraded your stability of the stand. Shims may be fine if all the strength is not needed.

The closer the rocker pivot point is to the attachment point the stronger your assembly will be. But what it has to be is what it has to be.

Sounds like he is on the right track now..............

yup that is all so true, i make my own shims to suport it so many diff combos

chappy89 wrote:Guys,

Keep having issues with the turbo motor. First time out, the rocker stand got pulled out of several of the threads in the heads. The heads were never heli coiled and the rockers were bolted to the factory alumium tapped holes. With 1200#'s of open pressure it pulled out the bolts. So, heli coiled all the holes, replaced the broken timing belt and bent valves, double checked all the pistons, and put it back together. This last time out, the car left hard, pulled the wheels, set the front end down and got on top of tires which spun them. The motor made about 22#'s boost at 8500 rpm, and pulled the aluminum perch out of the #2 exhaust stand. The heli coil was still attached to the bolt, it literally broke the head. The valves never hit the pistons, and all the cylinders were firing so no hydraulic problem.

Any ideas?

You got ant pics of car/motor? hows it fit ? what kind of hp numbers? Thanks Wes

dfree383 wrote:And no your A460's will not outflow properly preped C460's.

on a boosted application like his the motor will make whatever power the turbos are capible of making the motor just has to survive it.

chappy89 wrote:PS....my heads don't flow much less than a C head on the intake side...and they flow equal or better on the exhaust side!

Thanks again to Mike Schmidt over at TEA...they did an awesome job of getting the #'s I wanted out of these heads!

on a boosted application like his the motor will make whatever power the turbos are capible of making the motor just has to survive it.

The OP was claiming that his would.

The OP was claiming that his would. [/quote]

he seid they are close on flow numbers, if he put a set of C heads that flow 20 more cfm on the intake side it would still make the same power as it does now. flow numbers done mean shit to turbos. So he is correct, in his application C heads would not make any more power than what he has.

I'm not gonna get into this 'which head is better' thing.........being the turbo is in the mix. I do have the opinion that the C460 is better than a A460 natural or sprayed engine.
I do have customer that has 18 bolt A460 heads...unported...30+ boost ....low 4.20s in the 1/8 mile in a door car.
Don't ask me any questions because I do not have any answers :-} . Turbos aint where I live...all I know is they are poison........if you can feed it parts.

fstrthnu373 wrote:

flow numbers done mean shit to turbos.

I agree, he should save his money and buy D0VEs

Curt wrote:

fstrthnu373 wrote:

flow numbers done mean shit to turbos.

I agree, he should save his money and buy D0VEs

Keith Stone couldn't have said it any better............Boost is resistance to filling the cylinder and resistance is heat.

It's a balancing act.and a little voo doo

no need to get sarcastic I know c heads are better than a heads. but 20 cfm is like 3 psi so if it made 35psi with c heads itll make 38 psi with a heads not enough of a difference to drastically make inlet temps go up as long as you have the proper size intercooler, or if you run methonal it wouldnt matter. Not starting anything at all just say the differnece between the to heads for his deal, there is no difference in power, on a NA or nitrous setup huge difference. ask mike murrillo what heads he runs.

Curt wrote:

fstrthnu373 wrote:

flow numbers done mean shit to turbos.

I agree, he should save his money and buy D0VEs

https://www.youtube.com/watch?v=sTulqQZ822k turbos can make anything make power, this is coming from a guy who runs a nitrous motor.

fstrthnu373 wrote:no need to get sarcastic I know c heads are better than a heads. but 20 cfm is like 3 psi so if it made 35psi with c heads itll make 38 psi with a heads not enough of a difference to drastically make inlet temps go up as long as you have the proper size intercooler, or if you run methonal it wouldnt matter. Not starting anything at all just say the differnece between the to heads for his deal, there is no difference in power, on a NA or nitrous setup huge difference. ask mike murrillo what heads he runs.

The A460 head have over the C460 head ... Can use a lighter piston when turbo's are used.

fstrthnu373 wrote:

Curt wrote:

fstrthnu373 wrote:

flow numbers done mean shit to turbos.

I agree, he should save his money and buy D0VEs

https://www.youtube.com/watch?v=sTulqQZ822k turbos can make anything make power, this is coming from a guy who runs a nitrous motor.

What I saw was two failures on the dyno. Great power and very short lived. I dont have the time or resources to rebuild after every pass.
Couldnt tell, but it looked like stock heads. ^^^^^^^^^^^^^^^^^^

What I saw was two failures on the dyno. Great power and very short lived. I dont have the time or resources to rebuild after every pass.
Couldnt tell, but it looked like stock heads. ^^^^^^^^^^^^^^^^^^[/quote]

yeah i know thats why I seid before the motor just has to survive, pritty cool thow considering what they had to work with. I dont see myself building a turbo motor either to much startup cost maybe ill grow up one day sell my sbf and build an A headed nitrous motor.

DanH wrote:

fstrthnu373 wrote:no need to get sarcastic I know c heads are better than a heads. but 20 cfm is like 3 psi so if it made 35psi with c heads itll make 38 psi with a heads not enough of a difference to drastically make inlet temps go up as long as you have the proper size intercooler, or if you run methonal it wouldnt matter. Not starting anything at all just say the differnece between the to heads for his deal, there is no difference in power, on a NA or nitrous setup huge difference. ask mike murrillo what heads he runs.

The A460 head have over the C460 head ... Can use a lighter piston when turbo's are used.

I might disagree with that statement about "lighter pistons when turbos are used". Based on all the pistons I have weighed around here, the C-460 and Pro-Filer 205 pistons can generally be a little bit lighter by design, than an A-460 piston,,,,,,,,because the A-460 heads have valve cant and the relief on the outside edge has to be deeper. The C-460 and Pro-Filer 205 heads do not have a valve cant angle, and therefore the valve relief does not have to be as deep in the piston. Because the valve relief isn't as deep, the crown thickness can become less,,,,,and thus a lighter piston.

In years past we have had A-460 pistons burn through that point where the relief is the deepest, into the backside of the top ring land. It starts out looking like a little gas port hole. All of this is due to the cant angle. We've done things in regards to piston design to correct that problem now.

Back to a statement the OP made about his ported TFS A-460 exhaust outflowing a ported C-460 exhaust. I am curious if he was given test pipe numbers from TEA. If so, test pipe numbers will always be about 25 to 30 cfm higher than exhaust flow numbers without a test pipe.

Charlie Evans

chappy89 wrote:Guys,

Keep having issues with the turbo motor. First time out, the rocker stand got pulled out of several of the threads in the heads. The heads were never heli coiled and the rockers were bolted to the factory alumium tapped holes. With 1200#'s of open pressure it pulled out the bolts. So, heli coiled all the holes, replaced the broken timing belt and bent valves, double checked all the pistons, and put it back together. This last time out, the car left hard, pulled the wheels, set the front end down and got on top of tires which spun them. The motor made about 22#'s boost at 8500 rpm, and pulled the aluminum perch out of the #2 exhaust stand. The heli coil was still attached to the bolt, it literally broke the head. The valves never hit the pistons, and all the cylinders were firing so no hydraulic problem.

Any ideas?

happened to us also 2 years ago.

What block are you using? Steel or aluminum? And what is the valve lash that you are running???

Only thing that we changed after that is the valve lash and never had problems with it anymore.

I'm running the 18 bolt TFS heads with 400 intake and 375 exhaust seat pressure WW shaft rockers, 1.750 pivot 1.8 ratio single piece stands welded together.

Frank