Studs or Bolts - Downey Headers, 3.0
 

I researched the archives and saw several recommendations to use the stock studs instead of the bolts that are supplied with Downey headers. I also saw in the Downey catalog that they sell a stud kit for an extra snug fit for their headers. So, what would be the difference between the stock stud and a Downey stud. I'm getting a new crate engine. I assume it will come with studs installed. Shouldn't I just use those with anti-sieze and lock washers?

Oh, does anyone have any experience with the Downey gaskets? Is there a better gasket?

I have the Downey 4cyl header. I used the stock studs. Had to have two of them replaced when they stripped out while removing the stock exhaust manifold. The newer Toyota studs have a star-like deal on the ends for installing them, use those. The original studs had to be installed using the doubled nut technique.

I would not use the Downey gasket unless things have changed. I burned through two of them before installing a stock Toyota gasket. The downey gasket was thin with no extra protection around the exhaust ports. The stock Toyota gasket is much heavier duty and has metal rings around the exhaust ports. The downey gaskets were burning through from the exhaust port holes to the outside of the gasket. Haven't had a problem with the Toyota gasket so far (~10,000 miles).

I would go with studs for sure. I wish I would have. The bolts that came with my downey headers have a way of backing themselves out (on my engine anyway). Not to mention the ease of stripping the threads in your aluminum head (another problem I'm having). As for the difference between OEM studs and downey's, I have no idea.

Thanks. I guess I'll take a look at what the new engine comes with. The studs seem like the way to go! It sounds like the stock gasket idea is a good one too!

I forgot to ask. I read in one thread where it was recommended to get the header surfaced ("shaved"). Has anyone had any experience with this? It makes theoretical sense since the mounting flange/surface is likely to deform during the welding process on the header.

Never heard of shaving. But I forgot to mention that the passenger side header is going to come insanely close to your passenger side floorboard. Mine has literaly burned a hole in the carpet and melted my floor mat. You should look into a custom bend or some type of heat shield, wrap, or mat.

Do you have the ceramic headers? I was hoping that the heat dissipation would be about the same as with the stock manifold. There is a heat mat covering the firewall. I was thinking of getting some new heat mat and doing an extra good job of insulating. This will be easier with the engine out. I also intend to have a shop do a custom crossover and pipe leading to the cat. (Thanks to everything I've learned on yotatech!! :great: ) I already have a Jardine 2 1/4" exhaust with a Magnaflow cat.

The surfacing of the header is supposed to prevent the common leakage problem that many experience. I was just wondering how many people have done this. I'd never heard of this before.

Thanks for the help.

My headers are ceramic coated. They still get hot, very hot. Be cautious with your install, anything close to them will burn up. To date, I've lost a tranny kickdown cable, a spark plug wire, o2 sensor wires, and the corner of a floor mat.