MJSfoto1956
Well-known member
Dear list,
As many of you know I sport an UpSolute low-smoke-chipped 1.9L 1Z motor (from a 1997 90hp Jetta/Vento) installed in my 1987 VW Syncro Westfalia camper (5000lbs fully loaded). This past week we traveled throughout the Pennsylvania hills and I noticed some undesired behavior:
Specifically, at approx 2500-3000rpms under extreme load (meaning up hills at approx 70mph) if I "floored it" I got VERY high EGTs and quite a bit of smoke out the tailpipe (also bad fuel mileage). However, if I backed off to approx 3/4-7/8 accelerator pedal position, the EGTs dropped 200 deg F and no smoke (and much better fuel mileage). What's more, the amout of horsepower seemed to increase -- meaning I could accelerate slowly up the hill. This was NOT true if I floored it -- the van would decelerate up the same kind of hill.
Now remember that this is an "older" 1Z motor with the Garrett GT15 turbo and the UpSolute low-smoke chip. It seems to me that the engine UNDER EXTREME LOAD is starved for air at those rpms. I think this makes sense as the UpSolute chip was probably optimized for the VNT turbo which "supposedly" can pump out more air under the same conditions -- right?
If so, how can I increase the amount of air the motor gets? NOTE: I already run a Pipercross, 2 1/4" custom intake pipes and a Spearco air/water intercooler -- so I've already "maxed out" the intake. Current max boost appears to be about 16lbs with occasional spikes to 20lbs. Would "upping" the boost to 18lbs help here? I assume the only way to do that with my motor/turbo combo is the bleed trick -- right?
What about bolting on a T3 (non-VNT) turbo? Especially a water cooled one? (not sure I want to retrofit a VNT to my motor at this time -- too much time, costs, and uncertainty for now)
Or is it simply hopeless -- meaning that I will have to continue to "baby" the motor while driving in mountain areas??? This makes me sad, for my wife will never drive the van under these conditions...
Any insight greatly appreciated.
Michael Sullivan
As many of you know I sport an UpSolute low-smoke-chipped 1.9L 1Z motor (from a 1997 90hp Jetta/Vento) installed in my 1987 VW Syncro Westfalia camper (5000lbs fully loaded). This past week we traveled throughout the Pennsylvania hills and I noticed some undesired behavior:
Specifically, at approx 2500-3000rpms under extreme load (meaning up hills at approx 70mph) if I "floored it" I got VERY high EGTs and quite a bit of smoke out the tailpipe (also bad fuel mileage). However, if I backed off to approx 3/4-7/8 accelerator pedal position, the EGTs dropped 200 deg F and no smoke (and much better fuel mileage). What's more, the amout of horsepower seemed to increase -- meaning I could accelerate slowly up the hill. This was NOT true if I floored it -- the van would decelerate up the same kind of hill.
Now remember that this is an "older" 1Z motor with the Garrett GT15 turbo and the UpSolute low-smoke chip. It seems to me that the engine UNDER EXTREME LOAD is starved for air at those rpms. I think this makes sense as the UpSolute chip was probably optimized for the VNT turbo which "supposedly" can pump out more air under the same conditions -- right?
If so, how can I increase the amount of air the motor gets? NOTE: I already run a Pipercross, 2 1/4" custom intake pipes and a Spearco air/water intercooler -- so I've already "maxed out" the intake. Current max boost appears to be about 16lbs with occasional spikes to 20lbs. Would "upping" the boost to 18lbs help here? I assume the only way to do that with my motor/turbo combo is the bleed trick -- right?
What about bolting on a T3 (non-VNT) turbo? Especially a water cooled one? (not sure I want to retrofit a VNT to my motor at this time -- too much time, costs, and uncertainty for now)
Or is it simply hopeless -- meaning that I will have to continue to "baby" the motor while driving in mountain areas??? This makes me sad, for my wife will never drive the van under these conditions...
Any insight greatly appreciated.
Michael Sullivan