PDR HX-35 12cm or 14cm

[Ramafid]

I have the PDR HX-35 with the 12cm wastegated housing. I really like this setup but was thinking of switching to a 14cm non-wastegated housing. Has anyone done this swap. I'm looking at reducing top-end EGT's but don't want to sacrifice any mpg's while cruising. I know EGT's will increase under part throttle, is this something that will increase engine wear day in and day out? Thanks for the help.

 

[Steve St.Laurent]

I just put a PDR35/14 wastegated on my truck. I also have a 14cm non-wastegated housing here for testing. Once it warms up and the tracks open up I'll be testing all 3 combinations - 12cm, 14cm wastegated, and 14cm non-wastegated. I'll be doing testing on the dragstrip as well as towing my TT. It'll probably be a couple of months before I have the data though.

 

[Bob Wagner]

I just installed a Bank Bighead 14cm wastegated on Friday.



I will post some number's this week

 

[C Schomer]

I've had the PDR35/14, wastegate unhooked, since first produced. I see NO downside and I'm ultra fussy about smoke and driveability. Dynoed 292/812 @ 1250egt in Castlerock. I get as good of mpg as I've seen posted. 22 highway unloaded at 70 mph. 15. 5+ towing at 65 mph (25' 5er) and 16. 5+ towing at 60 mph. Spooling is better than stock 12. I get 36psi boost here and 40 at about 1500' alt. It cooks! Craig

 

[RCone]

I also, am curious about the difference between a wastegated 12 verses a wastegated 14 (PDR style of course). I tow a 8500# dry 5ver sometimes. I remember reading somewhere that IDAHOCTD tried a 14 over a 12 and I believe he suggested his EGT's went up while towing. How is that possible?. I only have a HY9 now and if/when I change I really would like to do it right the first time.



Roger

 

[Big White Beast]

Went from 14 to 12........

When I first got the PDR HX-35 I ordered it with a 14 non wastegated. Going from a HY with a 9 cm housing I didn't like the spool up I lost. The 12 had slightly better spool up and the 14 was a little smoother in the mid range. Boost #'s were similar for both housings.



If I towed a lot on the freeway's I would go with a 14. If you have to run around town a lot I would stay with a 12.



With DD2's and an EZ box on 3 I have never had an EGT problem, even with the HY. So if those are what your really worried about I probably would look at the more heavily fueled guy's for answers.



On the 02 which is empty most of the time I had Piers modify a HY turbo. No loss of spool up and slightly gain in boost. The turbo doesn't seem to run as hot though as it's pumping more air for the same RPM.



Garrett

 

[Ramafid]

Garrett,



Do you remember if the 14 ran hotter for just in town driving and open hwy cruising? What about wot with the 14. It should have run cooler than the 12 right? My EGT's in the winter are not bad but will creep up in the hotter months. I like staying under 1250 but in the summer will see 1350. Thanks for the help.



Anthony

 

[Big White Beast]

Anthony....

As I said my EGT's have never been a problem. I can't get them over 1200°. I didn't notice that much difference around town other than spool up. Once spooled the 14 ran fine.



On the freeway is when it shined. Hard to define but in the midrange it seemed way smoother.



If you don't mind a little lag, and it's not that bad I'm just fussy, go for the 14.



Garrett