Engine/Transmission (1994 - 1998) 14 cm wastegate or not

[dlefebvre]

Well, now that I have upgraded the injectors and with other bombs I have done, I am looking at changing the turbo from the stock to a 14 , but am not sure if I should go with a wastegate or not. How much spool time will I lose with a 14 versus the 12 ? Pretty impressed with the bottom end right now, but I need to drop my egt's when towing.

 

[Bhale]

I suggest you skip the 14 housing and go with a 16 non-wastgated housing. You might see a tiny bit of lag but very little and your egt's will be very comfortable

 

[Cummins4Life]

I've tried 12W, 16, 18. 5, & 21cm housings on my truck.



Only difference between the 12W and the 16 was you couldnt limit peak boost and I was pegging a 40psi gauge. Which isnt good because you're outside of the turbo's map and I'm sure drive pressures were getting pretty high as well.



The 18. 5 dropped EGT's down a 100* or so but I was still making too much boost for my liking.



The 21 was pretty darn laggy and by the time it would really spool EGT's were up past 1200*, kind of a pain when towing up hills.



All that being said I just ordered a 14W and I think it will be a good compromise of increased flow out of the engine with the ability to limit boost.