I never could get a TH400 to bolt up directly to a 460 Ford Big Block either

Mike

 

couldn't you shorten and retap the bolts?

 

Well, I guess I won't have to answer Paul's question now.

 

I don't know a whole lot about head bolts but couldn't you simple shorten the duratec head bolt by a half inch? Find a nut that will fit and get to cutting with a hacksaw. Remove the nut and it should be good to go. Isn't it that simple? :dunno:

 

the length of the shoulder is the problem. the threads don't go far enough up the bolt to take and shorten the bolt up.

humm....... have you looked into arp head studs for the tec?

spridget, is there any difference between the 2.5 and the 3.0 head bolts?

this realy sucks for the v8 guys.

 

2.5L and 3L Duratec head bolts are the same. ARP does make a set of Duratec head studs... listed for the 2.5L but obviously, they work on the 3L as well. Problem is, a set of ARP studs runs about $200 or more, and there aren't enough in a set to use on the V8. You'd need 2 sets, and have a lot of left overs.

So I take it new V8 head bolts are next to non-existent?

I wonder if a set of 4.6L V8 bolts would work.

 

I would just cut and rethread them. There are a lot of the head bolts but unfortunately FPS in Georgia has tried to corner the market on them by buying them all up.

 

Has anyone called Volvo to price a set of 4.4L V8 bolts? Or call a Yamaha dealer :dunno:


Does anyone know if the Yamaha 5.3L V8 (model number F350) is just an overbored 3.4L SHO engine?

 

the length of the shoulder is the problem. the threads don't go far enough up the bolt to take and shorten the bolt up.[/b]

You are correct. the threaded length for both bolts (SHO and Duratec) is the same - I need to thread further up the bolt. I think I'm going to stop by the parts store after work and get a die and give it a try.

 

More information (because I'm likely to forget if I don't post it):

1. The bolt is M10 x 1.5mm
2. The threads are rolled in, not cut. Therefore I can't cut them longer without altering the properties of the bolt and creating stress risers.

Looks like Duratec ARP studs are the next option to consider.

 

2. The threads are rolled in, not cut. Therefore I can't cut them longer without altering the properties of the bolt and creating stress risers.

[/b]

I was thinking about that too... I was looking at a Duratec head bolt and thinking you could not cut new threads. You'd risk having the bolt crack once it's fully loaded. The threads are rolled just like you stated.

 

It makes sense, as rolling the threads is a lot like shot-peening - it case-hardens them.

Luke, do you think you could get some Contour / Cougar Duratec guys to take some pictures and measurements of the ARP studs? I could afford to buy a set of the bolts just to experiment with as they're only $30, but a set of ARP studs is a little out of my budget right now.

 

Just shim the bolts out?

 

Just shim the bolts out? [/b]

I don't know if I'd feel comfortable doing that to my engine - we're talking about a good 3/8" - 1/2" of shimming. That's a lot.

 

Are you sure that the bolt would run out of threads if the bolt was shortened?

 

I could be wrong, but the Duratec bolt in that picture looks to be a TTY bolt, while the V8 SHO bolt is not a TTY bolt.

Would this make a difference?

 

I could be wrong, but the Duratec bolt in that picture looks to be a TTY bolt, while the V8 SHO bolt is not a TTY bolt.

Would this make a difference? [/b]

The V8 SHO bolt is TTY as well as the Duratec bolt.

Paul, I completely forgot about our conversation at my place a couple weeks ago. I'm going to go out in a little bit and take some pictures of the botls threaded all the way in the block without the head on, and we'll see.

 

Really? I guess only the V6 SHO isn't TTY then...

 

It makes sense, as rolling the threads is a lot like shot-peening - it case-hardens them.

Luke, do you think you could get some Contour / Cougar Duratec guys to take some pictures and measurements of the ARP studs? I could afford to buy a set of the bolts just to experiment with as they're only $30, but a set of ARP studs is a little out of my budget right now.
[/b]

Now why should I ask some one else to get pics when I have a set sitting on my shelf? :dunno:

I'll get some pics for you. I have some Vulcan head bolts too... I'll compare them as well.

 

Thanks Luke. If you could hold a tape measure up to one and take a picture that would be especially helpful.

 

Really? I guess only the V6 SHO isn't TTY then...
[/b]

Correct Hamal. I just recently learned all about these bolts on shoforum :thumb:

 

new ARP Duratec head stud
used Duratec head bolt
new Vulcan head bolt


used TTY head bolts stretch 1/8" IIRC.

I notice my used head bolt has threads higher up the shaft than yours, Daniel. What brand bolt is that? Mine is an original factory bolt.... I forget exactly which engine this came out of, but looking at my assortment of used bolts, 2.5L, early 3L, and late 3L all used the same bolts from the factory.

 

Still need to know how much (if any) thread is left when the tec bolt is used in the V8 and it is bottomed out. There may be enough thread already on the tec bolt when it is cut down to the V8 length.

 

Still need to know how much (if any) thread is left when the tec bolt is used in the V8 and it is bottomed out. There may be enough thread already on the tec bolt when it is cut down to the V8 length.
[/b]

Looking at the Duratec bolt in Dan's pic, it has about 2" of thread. The bolts I have all have about 3.5" of thread. Since Dan measured 3/8-1/2" of spacer needed to use his Duratec bolt, I think it's safe to say, if you have the 3.5" threaded Duratec bolts, you can cut of 1/2-3/4" and still have more than enough thread on the bolt.... still more thread than the SHO bolt.

 

So I am back asking the question of why can't the tec bolt be cut down to the V8 bolt length????

Do it Dan!!