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| The Full Race exhaust manifold is a work of art. 0.125″ thick schedule 40 stainless keeps the heat in and is virtually crack proof. Embee Thermo barrier coating is on the outside and gold piston dome coating in on the inside to help control heat. |
On the exhaust side of things, we added a Full Race Pro-Street exhaust manifold. Full Race is run by our buddy Geoff Raicer. We love Full Race, they make some of the best exhaust manifolds to be found. TIG welded from thick schedule 40 stainless weld el, a Full Race manifold won’t crack under brutal conditions. The thermal conductivity of the stainless is really low so underhood heat is minimized for a tubular product. Also the merges are exceptionally smooth for good flow.
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| On the turbo side of the Full Race Pro-Stock manifold, you can see how cylinders 1-4 and 2-3 are paired to feed into either side of the divided housing turbo. This helps the turbo spool much faster. |
The Pro Street Manifold is not the sexy twin scroll manifold used by the Sierra Sierra EVO but something designed to be compatible with the stock turbo that will package in the same footprint as the stock exhaust manifold, meaning it is compatible with off the shelf down pipes, O2 sensor housings and exhaust systems. Like the stock manifold it is designed to pair up cylinders 1-4 and 2-3 to make the best use of pulse energy to spool the turbo quickly.
To further reduce heat, we sent our manifold out to Embee Performance to have their thermal barrier coating applied to the outside of the manifold. Embee also applied their gold piston coating to the insides of the tubes for more thermal protection.
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| That’s a bad ass looking exhaust manifold! |
Now it was time for Naji to work the keyboards with another tuning session. The freer breathing EVO was able to run more boost, now up to 23 psi @ 3750 rpm and 19.7 psi at 7000 rpm. With the improved charge air cooling from the intercooler and the freer flow from the intake and exhaust system, the boost could be tolerated with a low knock count.
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| Our engine compartment is getting to look like a JDM lovers car. Oh nos! No crappy Chinese parts here. |
Power increased from a peak of 321 to 341 hp, a gain of 20 hp at 7200 rpm. The maximum gain was 29 hp. Torque increased from 274 lb ft to 308 lb ft, a gain of 34 lb ft! Not bad for an all bolt on EVO on 91 octane pump gas.
Stay tuned, in our next segment of Project EVO IX, we will rock some Cosworth cams!
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| Our power gains are big and fat, area under the curve is increased nearly across the board. |
Read More About Project EVO IX here!
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