So pretty much I have never really known much about turbo's...
I know that they are usuallly measure in MM, but I never know what people are talkin about when they talk about turbo's... I was wondering if someone could give me the "low down" on turbo's, and size's, and what not...
What is a stock turbo size for my truck?
Thanx

 

This would be good info for people to have.
But I cannot be the one to give it unfortunately.

What I can tell you is size makes a difference to power.
But with bigger turbo's, it takes more to make them run, than it does to make a smaller turbo run.

You can think of it like a house fan and a light breeze. The smaller fan will turn easily and faster than the larger fan in the same breeze, but if the air speed increases across the fans, the smaller fan eventually cannot go faster because the little blades cannot grab as much wind as the larger fan, thus gaining more from having a larger fan.

So the thing with a turbo vs your system is to have the optimal size turbo for the exhaust you are putting out. To much turbo, and the turbo will never spool up and gain you any boost.

To small of a turbo, and you will gain boost quick, but you will only gain so much.

(I think i got all that info right)

 

turbos get complicated. i can't remember the inducer size on our stock turbos right now, but you gotta know where the inducer and exducer on both the exhaust and intake side are. on the compressor(intake) side the inducer is the part at the front by the opening and the exducer is the part behind the housing that you don't see. the exducer size is larger than the inducer on the compressor side. on the turbine(exhaust) side the inducer is the part where the exhaust enters the turbine housing and hits the wheel and the exducer is the part where the exhaust exits the wheel into the downpipe. the inducer is larger than the exducer on the turbine side.



Now inducer and exducer size tell a lot about the flow characteristics of that particular turbo. the larger the more it can flow. the larger the wheel is on the turbine side and the larger the turbine housing the more it will take to spool that turbo, but the larger wheel and housing will allow for more top end performance. smaller turbine will give better low end performance, but will fall off on the top end.



if i am talking about a 66mm turbo then i am generally talking about the inducer on the compressor side. a 66mm modded H2E would usually have a 19cm exhaust housing on it to allow it flow better in the upper RPMs. a stock H2E is a 62mm. 62mm is good to run with stage 2 160/80% injectors up to probably 238 hybrids with 80% nozzles.



i gotta leave work now, but i will get back on later to post some more here.

 

Well you got the compressor side, which is done in MM. Like the famous 76MM Sledgehammer. The Inducer/exhaust sides I know are usually in inch like .84 or 1.00 inch. Then you got the wheel size which around here at the truck pulls the biggest one you can run in street class is 2.6 I hope this helps you. But turbos aren't as hard as people make them out to be. The smaller the exhaust side the quicker it will spool but most time it kicks up your EGTs alot higher. The bigger the compressor side, the more boost you can make, but it will spool slower. You want to find something thats right for waht you want to do, also don't expect to be super competative, with a mid range turbo.

 

From what I learned all turbos in Powerstrokes have the same wheels diameter from 1994 to 2003 or around this bracket.
But don't mistake the size with the output. Technology change at drastic speeds lately. Here are pictures of turbo wheel and cut out from 2005 Mercedes engine pumping over 200HP. Notice that the turbo is not much bigger than the drawing.
That baby spins over 200,000 rpm and take split second to get there. So thanks to the light weight -no noticeable turbo lag.

 

Towingcowboy, that 2.6 is referring to the inducer of the compressor, not turbine..

Another note on turbine housings, the smaller the housing the more back pressure u will have. U want to find a turbo that u can spool and get as close to a 1:1 ratio as possible. Heck if u can get your backpressure psi lower than boost pressure that's even better. So if u have small injectors like stage 2s then a good turbo choice would be like a 62mm stock h2e or gtp38r. 238 Hybrids r good with a 38r or modded h2e. 250cc hyrbids with like 100% nozzles would like a 71mm or so. Something like a k31 or mod an h2e to be around 71 or 72 mm. Maybe Even an s300.

 

I understand what inducer's and all that good stuff are, and turbine housing's, but when u get too the last two sentences of this last post i start going "wtf" too many numbers... ahhh, lol

 

Travis, in your professional opinion, with my mods, would a D66 be to much for my baby beans or could my baby beans handle a D66? Along with my other mods of course, lol.

 

whats the issue??? i know how you feel about the numbers, it can get confusing. Really in the end it comes down to how much fuel you want to throw in it, which will come down to how much power you want to make. turbo sizing will be determined by your selection of injector size and the use of your truck. see with our trucks we need to use more turbo for a given power level due to the relatively low injection pressures from our injection system when compared to say a common rail system or like the VP44 cummins and stuff. so with low injection pressure comes low atomization, more smoke, and less ability to use a smallish turbo b/c a small turbo will not produce the air needed to clean up the poorly atomized fuel. so i will throw this at you.. normally on a 7.3L this is how you would start off. a good turbo for stage 1 injectors would be either completely stock turbo housing and all or a D66 from beans(unknown turbo measurements) which will get you around 350-360hp. Then you have stage 2 injectors which usually a stock H2E(62mm), a decent s300(62 or 64mm), or a GTP38R would work well with which will get you around 400-450 hp. then there are stage 3 injectors which are usually 238cc w/ 80% nozzles which usually benifit from a modded H2E(66mm), GTP38R, or a decent s400 which will get you around 500-520hp. there are many other turbos out there as well such as the ones from WOP and stuff that i didn't mention as i was trying to keep it relatively simple.

Glenn, i'm not a professional by any means at all. i answered in your other thread, but yes a D66 would work great for your truck and injectors. you will like it for your towing needs as well. you should also see a nice little power increase with it and lower egts.

 

whats the difference between a d66 and a stocker for our trucks? with the 1.15 housing i ask, not like in my sig

 

Travis, I was just paying you a compliment. Didn't mean to put the added pressure on you to answer in a professional way, lol. I don't know if you read my copper & iron post but I need to do something about my loose turbo bearing. I think I'm going to order the D66 today. The guy on the email (Matt) said to also get the NON complex pedestal and the brass up pipe gaskets. I can see doing the pedestal but I heard the up pipes are a bitch to get at and mine aren't leaking, what do you think?

 

well Glenn it might be better to replace the up pipe donuts if you do the turbo. I was in the same boat not too long ago. Put in the D66, donuts were fine so I didn't mess with them. Now they are leaking, and I wish I would have changed them out when I had the turbo out. You'll like the D66. I have enjoyed it so far, but getting ready to switch to and H2E mount and different turbo's.

 

I thought you had to drop the trans to replace those? Removeing the turbo is good enough, huh? Its been awhile sinse I removed the turbo to put the 1.0" housing on, which according to Tim was a sourse of my problems. How many miles have you put on your D66?

 

You might have to drop the transmission to replace donuts I don't know though never had to change them until now. I have put maybe 10k on my D66

 

I'd hate to stack this on, but from my recent reading on turbo's, it says that there is an inducer and exducer on each side, exhuast and intake.

The inducer is where the air comes in, and exducer is where air comes out.

Travis has it right, but explained it more simply.

As for the OBS to NBS 7.3's. The wheel size might be the same, but the housing and wheels are different from OBS to NBS.