Turbocharger Bolts and Gaskets

[VelocitàPaola]

Here's a little information on bolt and gasket sizes and sources.

- 4 bolts from the turbo > star manifold:               10mm (M10) x 1.25
- 5 bolts from the downpipe > turbine housing:    10mm (M10) x 1.25
- 2 bolts from the wastegate > star manifold :      8mm (M8) x 1.25
- 2 bolts from the dump tube > TiAL:                     8mm (M8) x 1.25
- 2 bolts from the dump tube > Turbonetics:         7mm (M7) x 1.0

The lengths vary, but 25mm is a good place to start for the M10 bolts. Take a flange or a whole part to your source and try several bolts if you're feeling lazy. Otherwise, measure the lengths with a tape measure/ruler and record them (remember, measure everything in metric!).

Several site vendors carry this type of hardware made specifically for this application. Conversely, you can find the right sizes and grades of hardware at Grainger, McMaster-Carr and other online industrial supply sites.

Grade 8 is usually fine, as it stretches somewhat rather than breaking. Grade 10 is stronger, but if overloaded, the heads will shear off. If you have extra cash to spare and you're paranoid about your hardware failing, you can order from ARP. Their stuff is extraordinarily durable and reuseable.

- T3 turbo flange gasket
- 5-bolt downpipe gasket
- 2-bolt wastegate gaskets

Pick any supporting vendor that carries brand-name turbochargers and I guarantee they'll have these gaskets. If you were looking for MHI gaskets, then you would need to look for a vendor that specifically carries Mitsubishi turbochargers.