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borg warner turbo

61K views 111 replies 28 participants last post by  mikemoto017  
#1 ·
Ok got the fifth 4bt and it looks to have a borg warner turbo. Any one heard of this? Looks a little small but spools nice. Thanks in advance..
 
#8 ·
What was the condition of the engine it came off? Almost always turbo oil leaks are due to excessive crankcase pressure on the engine it was installed on. Turbos get blamed and rebuilt a lot when they are the victims, not the criminals.
I'd just run it and see how it goes.
 
#9 ·
Finally got specs from borg warner

Called emailed but got info

***** The turbine housing has a .7 A/R on the 171270. The compressor wheel has an OD of 68.6mm and an inducer of

40.6mm. The turbine wheel has an OD of 69.6mm and a 60.7mm exducer. *

Its a bit smaller than h1c

Looks a bit smaller than hx30 on the compressor too

This thing works good spools instant pegs 29 lbs with the fuel turned up

Only complaint is temps are hi

Got it dialed now hits 24 lbs full load and just hits 1200 pegged

Dont like it that hi but thats pegged normal is about 6-800 at 75 mph

Never seen another one out there

It will do about 9 lbs in first 20 in second 3-4-5th 24

Needle moves very quickly instant boost

Is it the miracle turbo

It sure is flat torque I can say..
 
#14 ·
The trend I am seeing is compressor intakes around 40mm and compressor OD's around 60-70mm. Mine is on the small side at 60mm, but the intake is comparable. With a slightly larger OD compressor wheel (68-70mm, I do have an option based on the new BW wheels) I could get the same spoolup, but with a larger A/R turbine housing which would give me better top end than I'm getting now.

It's not possible to convert cm^2 to A/R without knowing the radius. But it's not a huge deal anyway as the A/R needs to be considered against the turbine wheel inside too. The best way is to just look at the options the manufacturer gives us for that turbo and see where you are in the range. If it's an aftermarket turbo and they give a high and low A/R option, then the low one is always the diesel pick, the high is always the petrol engine pick.
 
#16 ·
I usually upload my videos to youtube, then embed them in a post. I recommend that route.
 
#17 ·
Older thread, but I just think it is interesting that we have a 460cu in. Valmet in one of our tractors that also runs a varient of the s2 Borg Warner series. But it is a s2b, Compressor inducer of 52mm if i remember correctly. Although it has a MUCH bigger exhaust housing than your little s2e :D
 
#18 ·
Just found out that this was a joint venture between bw and holset

They where trying to find happy place that the 4bt would like

Took 2 rebuild kits countless hours on phone and hair loss to finally get info

Everyone thought they knew part numbers for kits WRONG AGAIN

So waiting on another kit update soon..
 
#19 ·
Make sure to keep us updated with whatever info you find out about this turbo.
 
#20 ·
I bet if u installed an external wastegate u could control the egts better so u could add a bit more fuel.
 
#22 ·
Whatever. I'm going to give the good advise whether not it is used or not. Deal with it!
 
#23 ·
when you say "I bet if you put a wastegate on", you`re GUESSING that something will work. that is NOT good advice !! if you have put a wastegate on a non waste gated turbo and then recorded the difference before and after the wastegate,then you have good advice. I don`t understand all I know about turbo maps, but Dougal does and when he comes up with examples and makes suggestions about what will work or not, THAT is GOOD ADVICE, that you can take to the bank.
 
#24 ·
I would not say something if I haven't had success with it before. Sorry threetoecrow.
 
#26 ·
Well a lot of people including myself has said it, the 4bt needs a twin scroll 9cm turbine housing. I guess this turbo proves it. I wish they were readily available.
 
#27 ·
I picked up an S2A off a John Deere Genset. It had a larger pattern than T3 on the exhaust. I don't think it was T4, but I didn't measure it. I was able to re-drill the pattern to T3 and bolted it up. Its a twin scroll and the ports were T3 size, matched the gasket perfectly. Now I just need to finish the rest of the project so I can try it out!!