Differences between 4294 and 4202 and 4202R?
- Thread starter SIKDMAX
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4294 is small LOL, the 4202R is rebuildable and ball bearing/watercooled which is the one I would use you can get 4202 journal bearings for A LOT less than its BB brother.
The GT4294 and GT4202 are the same center section and Turbine side. The Compressor side is the difference. The 94 has a Comp wheel that measures 94mm exducer by 70.3mm inducer. The GT4202 has a comp wheel that measures 102mm exducer and 74.3mm inducer. Power wise there is about a 150hp -200hp difference. GT4294 is good for around 650rwhp and the Gt4202 around 850rwhp. The GT4202R is basicly a GT4202 with a ball bearing center section. It is not nearly as easy to rebuild as the plain bearing and cost far more. It is how ever water cooled. There is an idea that the water cooling makes it better but that is bogus. The reason it is watercooled is because the it has an oil flow restrictor. Ball bearing dont like nearly as much oilf flow. the problem with that is that the oil is the coolant in a journal bearing turbo. So with less oil flow the water cooling is needed to help cool the center bearing section. The ball bearing will spool quicker but not alot like they like to make you think. 200 to 300rpm is all. Other big difference between the GT4202 and the GT4202R is cost. $1500 vs $2300. Depending on what your goals are you might consider a S472 Borgwarner. Power wise it is about right beetween the the GT4202 and GT4294. It is good for around 750rwhp. It spools a good bit better that then both GT42s IMHO and can be had aroung $750. It will pretty much bolt right up to a GT4202 mount kit also.
The compressor maps are similar. The s475 flows a touch more air around a 3:1 PR...but who run 30PSI. The 4202 can run a little higher PR at just over 4.5 where the s475 tops out at about 4.0 PR But most people run these turbos off their maps so who knows which one is more efficient in the real world. Also you are comparing a BB to a journal bearing. A fair test would be a GT4202.
so whats the dif between an journal bearing that is oil+water cooled and a jounral thatn is just oil cooled?
DBB vs journal example form honeywell in spool up
here is honeywell's reasoning for oil and water cooled turbos vs just oil cooled
so whats the dif between an journal bearing that is oil+water cooled and a jounral thatn is just oil cooled?
DBB vs journal example form honeywell in spool up
here is honeywell's reasoning for oil and water cooled turbos vs just oil cooled
Because a gt4202 and a gt4202R have different compressor wheels
4202 74.3mm 102mm 0.60 53
4202R 74.7mm 102.3mm 0.60 53
not much .. .3mm or .011" difference on comp.
both run the same turbine 82.0mm 84
DBB variant can support ~20% more power then the journal variant why?
could it be that the R is running cooler and more effcient then the journal?
repeat
I wish I had a map for my turbonetics 76mm midframe. I wonder if it will be competitive with either the 4202r or a s475
Good Thread!
Maybe ill have my S472 opened up some before i put it in? I know an 80mm will fit (machined compressor housing of course)
Anyone know how much bigger i could go? Wonder if an 85mm wheel is doable?
Maybe ill have my S472 opened up some before i put it in? I know an 80mm will fit (machined compressor housing of course)
Anyone know how much bigger i could go? Wonder if an 85mm wheel is doable?
Depends on what turbine the S475 has. If the S475 has the 83mm turbine the GT4202 will hand it its butt. But if you go up to the 87mm turbine the S475 will win.
They are spining things a little there Adam. The real reson for watercooling a ballbearing turbo is to help aid cooling because the ball bearing can not handle the oil volume needed to cool like a plain bearing. If you pump unrestricted oil volume into a ball bearing all the space will be filled by oil. the surface tension will be to much and the balls will not spin. You will get what is called bearing skid. Ball bearing work much better with just light coating of oil. The trouble with that is that the high oil flow in plain bearing turbo is what cools it. So to keep temps in check they add water cooling to ball bearing turbos.so whats the dif between an journal bearing that is oil+water cooled and a jounral thatn is just oil cooled?
DBB vs journal example form honeywell in spool upAdd cooling capacity is all. Spool of a water cooled plain bearing is no better then a non watercooled plain bearing
here is honeywell's reasoning for oil and water cooled turbos vs just oil cooled
The trouble with Turbonetics stuff is the turbine. Your turbine is the same as GT40 IIRC.
The biggest natural S400 is the 80mm. The larger comp wheels like the 88, 90, and 94 are from the S500 series turbos. The trouble these IMHO is that the S400 turbine wheels are not high flowing enough to support the bigger wheel on a diesel. That may work on a gasser but I would rather see the turbine that was made for the comp wheel com with it.
We did some testing in a sled pull application and found it to be lazy on the bottom end and had a hard time keeping up on it at the other end of the track. (sled Pull Application)
This was with a few different housings and housing needed created some drive pressure we do not like to see. I believe they have made some adjustments since the version we where trying last season. As for BB vs. JB we use as much as we can per applications a BB over a JB. All of our new turbos that we tested last season ended up being BB. We have seen a BB be more forgiving then a JB in over spun applications. The 2.8 and the 3.0 chargers have almost instant spool up and are based off a GT42R cartridge.
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Bullseye also sells an S485 available with either an 87 or 96 mm turbine inducer. I think I have a compressor map for it somewhere. I wonder how well the turbine side flows.
http://www.bullseyepower.com/S400.asp
Nevermind, it was an S480 compressor map. Anyway, here it is.
http://www.bullseyepower.com/S400.asp
Nevermind, it was an S480 compressor map. Anyway, here it is.
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