I did search through many threads unable to find what i was looking for... so here is my poll...

I need some input from the members of EvoM...

What head studs do you recommend?

ARP L19s

Cosworth

Magnus <- overkill im sure.

Quick Spec sheet.
4G64 bored to 87mm
Wisco Pistons
Eagle Rods
Stock Crank
ARP Mains.

O-Ringed

Evo 8 head
PnP
HKS 280 Cams
REV valve train (T retainers, etc) (1mm over intake, 2mm over exhaust)

GT4088 Turbo OS
Manifold (Undecided)

Thanks Everyone.

 

Just the standard ARP's will be fine. We are starting to have issues with the standard ARP's at 900 whp and we are going to the L-19's but haven't yet. One things for sure, they don't give them away. So if your shooting for 900-1000 whp go with the L-19's but if not the standard ones seem to be fine.

 

Thanks for the quick response, what kind of issues are you having?
I forgot to mention that my head is also cryo'd. Any input you have is greatly appreciated!

-Rob

 

Yeah i agree with Head Dynamics.......standard ARP head studs should be fine.

 

Thanks also,

Now, ive contacted SBR, according to one of their techs, the Cosworths are as strong as the ARP L19s!

Im sure i know this answer, but, Since the standard ARPs run about 120ish, i might as well get the Cosworth ones for $50 more, correct?

Appreciate your help guys!

 

We have Class One High Performance Engines O-ring our blocks and they mill the surface of the block, cut grooves in the deck and install the wire in the block and then they take and mill the o-rings down to where they are only sticking out of the block .005 to .006 and that seems to work the best so far. The issue we are having is that when the boost comes up the head is lifting and spraying coolant out of the back of the head, but all the combustion process is still being contained. We also machine out the bottom of the head where the coolant passage is under the exhaust port and weld it up solid. We are just now having issues, but when the boost comes down everything is sealing up fine.

 

standard ARPs, will do just fine till about what head dynamics said

 

A friend of mine is having a similar issue with his 1G AWD.... around 30psi the head is lifting.

Thanks again for the info!

Rob

 

Lifting heads is the suck.

You know what my vote is.

 

SBR

Just get the standard ARP HEAD STUDS.. unless your going for 1000 hp

 

I'm running the AMS/TMS studs which i believe are L19 hybrids correct

I put down 510 on our Mustang dyno and decided that i'd spend the little extra for the piece of mind and the fact that i can re-use them w/o fear of stretching.

On a side not we have a 2G w/ a 40R that put down 589 on the same dyno and was running standard ARP's.

They held on the dyno but once he took a spin on the street he lifted the head and you could see all 4 cylinders push coolant in the same spots.

We are swapping to the Magnus studs tonight.

Also my block is O-ringed his is not.

I run an oem head gasket and i can't remember the exact brand he will be running.

 

i didnt know there were other options beside arp lol

 

Exactly... DSM's have been pushing heads off for an eternity. I've watched too many big motor 4g63 cars that get driven on the street push heads off on ARP's to follow the... "oh, standard ARP's are fine"
I've seen o-ringed heads push on ARP's. The stud just stretches. Nothing you can do. Especially if you're spiking cylinder pressure up with timing to spool something big. Even without knock.

 

Yup...yup...that's why i started a thread a few days back to see what the evo guys were doing.

I was told by numerous DSM guys the same thing and they must know a thing or two about this stuff by now. Evil_Eagle is one of the guys that rec'd the Magnus studs but those are $300+ and i didn't think the car needed that at this point....besides the AMS/TMS studs are said to be good to 800+

We were pushing 34-35 psi on the 2G fwiw

 

Alot of great info here, this is what worries me about lifting the head etc. I was able to get a hold of cosworth to find out their tensile strength...

Company - tensile strength - price

AMS/TMS =210,000 - 260,000 ~$249
ARP = 190,000 ~$110
ARP L19 = 230,000 - 260,000 ~$299
Cosworth = 200,000 ~$175
Cosworth new head studs = 260,000 (estimated cost of 5% increase over current price -release date 30-45 days) ~$190
Magnus =? ~$375

I may just end up going with the AMS/TMS ...group buy or EvoM discount?

Thanks all

Rob