Attention: TDR Forum Junkies Here are my observations with using an ATS manifold with an aftermarket turbo. Take them for what they're worth!
In early January 2005 I installed an HTB2/62/12 turbo, but I kept the stock manifold. This was despite all the good advice from numerous members to do the manifold and turbo at the same time :-laf . These are the before observations:
-The pyro tap on the stock manifold was right before the turbo flange measuring the back 2 cylinders.
-With the stock manifold and the TST/VA stack I could peg the boost gauge pretty darn (scary!) quick up to 45 psi.
-I wouldn't see the EGT get higher than +/-1250*, especially getting on the peddle at low boost and ~2000-2200 rpm, and then the EGT would settle at about +/-1100* at WOT.
Last week I finally installed an ATS manifold and these are my after observations:
-I installed the pyro tap on the ATS manifold right before the turbo flange measuring the back 3 cylinders.
-With the ATS and the TST/VA stack at the same levels used as above, the boost comes on a lot smoother. It's still quick, but not blink of the eye quick like before. Max boost was 42 psi.
-The max EGT would hit +/- 1400*, especially getting on the peddle at low boost and ~2000-2200 rpm, and then the EGT would settle out to about +/- 1050* at WOT.
What's interesting is that:
-the EGT at the same measuring point peaks higher (during low boost fueling at ~2000-2200 rpm), but settles out about 50* lower. Is this because the hot exhaust gasses are now more in the manifold rather than backed up near the cylinders?? Larger diameter exhaust runners should equal slower exhaust flow... so then that would explain that...
-the boost spike is about 3 psi less indicating a more balanced flow to the turbo.
Edit: These observations are not towing. I would imagine that towing one would see better EGT numbers due to truck working harder and generating more boost?
In early January 2005 I installed an HTB2/62/12 turbo, but I kept the stock manifold. This was despite all the good advice from numerous members to do the manifold and turbo at the same time :-laf . These are the before observations:
-The pyro tap on the stock manifold was right before the turbo flange measuring the back 2 cylinders.
-With the stock manifold and the TST/VA stack I could peg the boost gauge pretty darn (scary!) quick up to 45 psi.
-I wouldn't see the EGT get higher than +/-1250*, especially getting on the peddle at low boost and ~2000-2200 rpm, and then the EGT would settle at about +/-1100* at WOT.
Last week I finally installed an ATS manifold and these are my after observations:
-I installed the pyro tap on the ATS manifold right before the turbo flange measuring the back 3 cylinders.
-With the ATS and the TST/VA stack at the same levels used as above, the boost comes on a lot smoother. It's still quick, but not blink of the eye quick like before. Max boost was 42 psi.
-The max EGT would hit +/- 1400*, especially getting on the peddle at low boost and ~2000-2200 rpm, and then the EGT would settle out to about +/- 1050* at WOT.
What's interesting is that:
-the EGT at the same measuring point peaks higher (during low boost fueling at ~2000-2200 rpm), but settles out about 50* lower. Is this because the hot exhaust gasses are now more in the manifold rather than backed up near the cylinders?? Larger diameter exhaust runners should equal slower exhaust flow... so then that would explain that...
-the boost spike is about 3 psi less indicating a more balanced flow to the turbo.
Edit: These observations are not towing. I would imagine that towing one would see better EGT numbers due to truck working harder and generating more boost?
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