1FZ-FE ARP Head Studs Installed with Part#

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guzzla

guzzla

10 Year 15 Year
Joined
Sep 17, 2007
Threads
26
Messages
395
Location
Skippy's Wonderland (OZ)
There has been much confusion about what is the best ARP head stud to install into a 1FZFE. I'm aware others have expressed concern at the fact the Toyota Supra studs, as commonly used with great success in the past, could do with slightly more thread length. However, after my own investigations and speaking with my engine builder, who has significant experience building 1000+HP supercharged and turbo charged engines, it's clear that the ARP studs I have used and installed work perfectly - as the images show below...

This is the ARP part number I used.



This is their over all length.


This is the studs and nuts installed. When torqued down properly, the studs finish flush fractionally proud of the top of the nut. As my engine builder said, there's no point having additional thread extending past the top of the nut as there is no additional clamping force or reliability offered since the amount of thread engagement is simply determined by the depth of the nut itself.


I'm sure others may have differing opinions, and I accept that. However, based on my own experience, and that of a highly experienced engine builder, the ARP studs myself and many others have used work just fine.
 
A couple of years ago I sent ARP's marketing department a head bolt and asked them to match it up. I also told them the Supra studs were a tad too short. A week later they sent me a set of bolts that were about 10mm longer. After assembling the engine I reported back to them that they were the perfect length. Supposedly, they were going to look into a kit for the 1FZ-FE. These are the only pics I have:

DSCF2450.jpg


DSCF2447.jpg
 
you're the first that I know of who had them work properly. It has been well documented that when using this kit you need to not install the studs fully to get the needed height to protrude out of the nut. I've tried this kit on two different motors and that was the case in each.

Then again you ordered the Opel kit and couldn't even get the nuts to seat on the head. So there definitely seems to be something at play here.
 
I wish ARP would just come out with a kit for our engines, take away all the confusion.
 
landtank said:
you're the first that I know of who had them work properly. It has been well documented that when using this kit you need to not install the studs fully to get the needed height to protrude out of the nut. I've tried this kit on two different motors and that was the case in each.

Then again you ordered the Opel kit and couldn't even get the nuts to seat on the head. So there definitely seems to be something at play here.
Click to expand...

That's true, Rick. The strange thing is that there's a heap of guys in Australia using the Supra stud kit without the issues some of you guys have experienced. And as you said, the undercut Opal stud kit I got first time was next to useless yet it worked perfect for you guys in the US. The more I think about it, the more I'm convinced there are slight casting differences, though I can't explain why, that seems to be causing the confusion.

It might be of benefit if GOTMUD could post the part# of the studs he used by comparison, and if possible, explain if the studs were 10mm longer in the unthreaded section or the threads were 10mm longer each end.
 
this is the first that I realized that you are in Oz. I got a spec sheet from ARP a while ago and filled it out. I wish my computer was running as it would be nice to have you compare my measurements with what you have.

It will likely be a week before my computer is back running, what is your reassembly schedule?
 
gotmud said:
A couple of years ago I sent ARP's marketing department a head bolt and asked them to match it up. I also told them the Supra studs were a tad too short. A week later they sent me a set of bolts that were about 10mm longer. After assembling the engine I reported back to them that they were the perfect length. Supposedly, they were going to look into a kit for the 1FZ-FE. These are the only pics I have:
Click to expand...

I'm still going around with these guys. They advertise the ability to custom make hardware and then I've been given the runaround ever since I ask for the procedure to do that.

It's been frustrating to say the least.

The last guy was all excited that there was a new kit for a 1.8l corolla engine. Who is boosting those?
 
The guy I spoke with at ARP thought the "Opel" V-6 kit would work, according to the book dimensions. I'm not sure what they ended up sending me, but they were slightly longer and solved the issue of not having enough thread. You can see in the 2nd image the box they came in, but don't recall if there was a number on the box.

Which end was longer??? There were several threads sticking up past the nut when everything was torqued down:meh:

I'll see if I can dig up the emails from ARP.
 
landtank said:
this is the first that I realized that you are in Oz. I got a spec sheet from ARP a while ago and filled it out. I wish my computer was running as it would be nice to have you compare my measurements with what you have.

It will likely be a week before my computer is back running, what is your reassembly schedule?
Click to expand...

Sorry, Rick, the head is already bolted on. But I have a photo in my first post showing the length of the Supra studs to compare against the other options.

It should also be noted that another Australian based member, MS-75 (aka SuperCrown) who runs the 600+HP, 10.7sec 1FZFE in a Toyota Crown has used the supra studs for many years without incident.
 
guzzla said:
Sorry, Rick, the head is already bolted on. But I have a photo in my first post showing the length of the Supra studs to compare against the other options.

It should also be noted that another Australian based member, MS-75 (aka SuperCrown) who runs the 600+HP, 10.7sec 1FZFE in a Toyota Crown has used the supra studs for many years without incident.
Click to expand...

that might be so but I'm not really interested in that info. I just want a stud that works as ARP intends it to with our engines. That would be fully seated in the block and the stud protruding through the nut by a few threads.

You don't get that with the Supra studs. Even on your engine it doesn't seem that the threads are protruding sufficiently through the nuts and you are using the washers from the Supra kit which is also technically sized wrong for our bosses. The washers in the Opel kit are a larger diameter and thicker which more closely matches the stock ones Toyota spec'd out for the engine.
 
Why not use the OEM Toyota head bolts, are they weaker or something?? IDK.
 
I'm assuming these guys are interested in turbo/supercharging. Arp or another quality head stud is a stronger solution/requirement for someone running boost. Just google "broken head bolt turbo" and you'll see some prime examples of why people are running studs. There are a few other advantages too, but they do have downsides. :) Oh yeah... and they're reusable.
 
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OK I get it now, reread the first post "1000+HP turbo charged" so much boost you can blow the head off using the original head bolts. So the main advantage to using ARP studs in a normally aspirated engine is that they are reusable?
 
IMHO I would not use them in a "normal" engine. I can't speak for the problems resulting in members wanting to use them in landcruiser engines, but with VW they tend to be a pain when not really needed on stock engines.
 
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