PTE 6262 Ported shroud? Benefits over E Cover?
- Thread starter Sal 87WE2
- Start date
- Joined
- May 26, 2001
The SP cover or "S Ported Shroud" style, gives you surge protection during part throttle driving and decell from WOT conditions. The ported shroud incorporates holes and a recirculation groove that have been machined into the compressor cover. These allows excess air flow that the motor can not take in, a place to escape or recirculate back in to the inlet of the turbo. A surge condition happens when excess air flow that the motor can not take in, or injest, stops the rotation of the turbo. This condition creates extreme thrust loading to the bearing system and can lead to premature bearing and or seal failure if not addressed. The barking or chuffing sounds you hear when you let off the gas from a WOT pull, or when doing a burn out, is the sound of the turbo surging. AKA, the turbo is spinning forward and backward at tremendous speeds.
The recirculation groove and holes give the excess air a place to go, which keeps the rotating assembly spinning in the same direction. Dramatically reducing and in some cases eliminating the damaging surge conditions. On all street driven applications, I always recommend the Ported Shroud style compressor cover. Whether it is an SP style or an HP style compressor cover.
The E cover is not available with a ported shroud and is typically used on applications that want to keep everything as stock appearing as possible. IE: not changing MAF pipe or changing the discharge hose. As far as power is concerned there are no real power gains to be had with a Buick application, going from an E cover to a S sized cover.
Each compressor cover has a different A/R, just as a turbine housing does. With regards to the compressor cover A/R, it mainly has to do with internal sizing and it's flow capabilities at extreme boost levels. With our limited window of boost we have to work with (20-35 psi range) compared to other import applications who can run significantly higher boost levels, we have not seen any dramatic differences in power between the E cover or the S cover. It does not hurt performance either. Which undoubtly everyone has seen with the performances of THS cars equipped with E cover 6768 turbos.
Here are some pictures of the different types of covers.
1st Generation E cover.
2nd Generation E cover.
Current SP cover for 55, 58, 62 and 67 CEA wheel equipped turbos.
This last picture, clearly illustrates the ported shroud. You can see the machined groove and the drilled holes that allow the excess airflow a place to recirculate back through, to the inlet of the compressor. On a street car, especially on one with goals of anywhere in the 10's, I would highly recommend an SP cover on the 6265 or 6262 turbos.
Hope some of this helps.
Patrick
The recirculation groove and holes give the excess air a place to go, which keeps the rotating assembly spinning in the same direction. Dramatically reducing and in some cases eliminating the damaging surge conditions. On all street driven applications, I always recommend the Ported Shroud style compressor cover. Whether it is an SP style or an HP style compressor cover.
The E cover is not available with a ported shroud and is typically used on applications that want to keep everything as stock appearing as possible. IE: not changing MAF pipe or changing the discharge hose. As far as power is concerned there are no real power gains to be had with a Buick application, going from an E cover to a S sized cover.
Each compressor cover has a different A/R, just as a turbine housing does. With regards to the compressor cover A/R, it mainly has to do with internal sizing and it's flow capabilities at extreme boost levels. With our limited window of boost we have to work with (20-35 psi range) compared to other import applications who can run significantly higher boost levels, we have not seen any dramatic differences in power between the E cover or the S cover. It does not hurt performance either. Which undoubtly everyone has seen with the performances of THS cars equipped with E cover 6768 turbos.
Here are some pictures of the different types of covers.
1st Generation E cover.
2nd Generation E cover.
Current SP cover for 55, 58, 62 and 67 CEA wheel equipped turbos.
This last picture, clearly illustrates the ported shroud. You can see the machined groove and the drilled holes that allow the excess airflow a place to recirculate back through, to the inlet of the compressor. On a street car, especially on one with goals of anywhere in the 10's, I would highly recommend an SP cover on the 6265 or 6262 turbos.
Hope some of this helps.
Patrick
Yes it does. I just re-did this set up on my car. Without the angle boss the iac pushed into the 4" to 3" bending reducer. The angle boss is a nice piece and worth the money in my opinion.
-Dave
Ok, Thanks Dave!!
This deffintly helpped me ,I want to know is it worth the investment to go Ball Bearing ,Or buy journal . I know there is a faster spool. But will I noticed the difference.
The car I'm bringing back has 212/212 flat ,J&E , Light port ,65 lb ,Alki .Translator map ,2800 stall
The car I'm bringing back has 212/212 flat ,J&E , Light port ,65 lb ,Alki .Translator map ,2800 stall
Similar threads
