Originally posted by Sean Raymer:
Just curious, what is your compression on all 4 cylinders? what condition are your stock rods/pistons and crank/bearings in? From what i've read on 2gnt most guys are lucky if they can run 8-10psi on a stock block/internals, max i've seen is 12psi. Every engine is different, your internals could be near perfect where someone else may have below-average or visa-versa its impossible to tell... so to say I can do it because others have is far-fetched. Why risk ****ing up your stock rods/pistons/crank and possibly more by running too high boost, run a safe level of boost, save up for a proper rebuild then do it right the first time.
sidenote: What psi did you dyno/tune at? what were your numbers (a/f, hp, trq)?
I'd definitely heed his advice.
420A are not designed for boost. The pin connecting one of my rods to the piston was in pretty bad shape. And I had it @ 6 psi. Like he said. If you want to go all out. Keep it at low boost and save $$$ for a rebuild. Otherwise you'll be stuck with a blown motor.
The block of the engine is pretty damn solidly built. But the rest is not so great, especially the notorious headgasket . So watch out. And I'd also watch out for the clutch. Mine already had a crack in it.
BTW my spool. Well, the turbo is a T3/T4 with E-compressor sized housing.
And if it spooled any faster, I'd be going into boost at idle.
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