Turbo Characteristics

[big_eskimo]

I have a question about the characteristics of the three most common turbo's in the DSM aftermarket community. Through TONS of reading I'm absolutely deadlocked between a 14B, a T25, and 16G. I never ever go to the track and I rarely even go above 5000 RPM's. I know that the T25 is notorious for having a narrow power band, but I would really like the quickest spooling turbo considering my driving characteristics. I have experienced a 14B but it was dying at the time and I was babying it so I have some idea of the power it makes. My car is a daily driver and I'm not a hot rodder from stoplight to stoplight, but I do enjoy some spirited driving from time to time.

So would it be completely nuts to put a T25 on my 1G?

Should I just get a new 14B?

How much longer does it take to spool a 16G on a very mildly modded car compared to a T25 or a 14B?

Thanks in advance,
R.J.

 

[DSMcamaro]

It wouldnt be worth the work of putting a t25 on your car. To me it sounds like you should just get another 14b. If you rarely go above 5g's and dont go to the track i wouldnt waste the money on a 16g.

 

[Black94DSM]

Viewing your Profile you have ZERO mods on your car. I say get another 14b, just make sure it dont have any shaft play and looks to be in good condition.

 

[delta448]

What mods do you have? Do you have a boost controller? Exhaust? K&N?

From my experience, a 16G is not all that slow in responding if you have a MBC, exhaust and almost anything except the stock airbox to filter with. My mods are definitely helping my turbo spool quicker than it would on an otherwise stock DSM though.

The larger turbos have slightly more lag, but that could also be beneficial if you are looking for better gas mileage by keeping you out of the boost longer, thus requiring a little less fuel around town. Of course, you may consequently find a new love of the higher rpm band with a larger snail. But if you want quick boost buildup, I'd stick with a 14B. I really don't recommend a T-25, but I'm the kind who loves chasing the redline, so I'm biased.

 

[big_eskimo]

Thanks for the responses, I kinda figured the T25 wouldn't be worth the effort, I think I'm just gonna go with another 14B, but just out of curiousity sake how much quicker does the T25 spool than the 14B? I remember reading somewhere that the 2G has a higher compression ratio than the 1G and that would definately effect spool up. So maybe it wouldn't be as responsive on a 1G, I don't know just a thought.

How difficult it is it to rebuild a 14B? Mine took a crap on me last winter and by the time I put her down last my turbo was smoking bad. Is there a certain point to where you can't rebuild one?

About the mods, I just purchased a MBC and a boost gauge. I'm also in the market for a 2G exhaust manifold that I'll end up porting. That should suffice until I get some more cashflow.

Eventually I want to have either a Supra SMIC or a FMIC, although I think a front mount might be a little overkill for a 14B...yes...no? I would really like the bar and plate SMIC seen here http://www.thespeedfactor.com/ic_dsm2.html but a $400 price tag seems a bit steep.

I will also be getting a GM MAFT for a blow through set up, 2.5" IC pipes and intake pipe, a functional Cyclone intake manifold, a 2.5" or 3" turbo back(more than likely the 2.5", I have a feeling that a 3" on as mild a setup as mine would be a bit much), perhaps a rewired Walbro 190 LPH fuel pump for a little insurance, and definately a logger.

I have been reading and searching a lot around tuners but haven't really asked many questions so feel free to chime in, any advice would be greatly appreciated.

R.J.

 

[DSMcamaro]

Eventually I want to have either a Supra SMIC or a FMIC, although I think a front mount might be a little overkill for a 14B...yes...no? I would really like the bar and plate SMIC seen here http://www.thespeedfactor.com/ic_dsm2.html but a $400 price tag seems a bit steep.

I will also be getting a GMAFT for a blow through set up, 2.5" IC pipes and intake pipe, a functional Cyclone intake manifold, a 2.5" or 3" turbo back(more than likely the 2.5", I have a feeling that a 3" on as mild a setup as mine would be a bit much), perhaps a rewired Walbro 190 LPH fuel pump for a little insurance, and definately a logger.

I have been reading and searching a lot around tuners but haven't really asked many questions so feel free to chime in, any advice would be greatly appreciated.

R.J.

Wow, sounds like a whole differnt person than before. why do you want all these mods if you dont drag race or ever push your car much? I guess if you looking at all those mods in the future I would think about an evo III 16G.

 

[big_eskimo]

Wow, sounds like a whole differnt person than before. why do you want all these mods if you dont drag race or ever push your car much? I guess if you looking at all those mods in the future I would think about an evo III 16G.

, just because I don't mob it too hard I still enjoy the pull to 5 MPH over the speed limit.

 

[dalatinromeo]

So would it be completely nuts to put a T25 on my 1G?

No, dont do that. Put another 14b on your 1g; that would just be downgrading. T25

Should I just get a new 14B?

That would be a good idea, not a new one though, a good condition used one.

How much longer does it take to spool a 16G on a very mildly modded car compared to a T25 or a 14B?

16 will hit full boost by 3100 RPM's. Pretty fast spool up. You will scarfice some spool up but very little.

If you plan on getting injectors and some way to tune your car(DSMLink, SAF-C), and all those other mods you mentioned. I would go with a 16g path.

Hopes this helps, Stay boostin!!

 

[big_eskimo]

OK,
So after some furter research and getting more understanding of turbo's I have a new question. So apparently reaching full spool, and hitting a certain PSI has no real weight, what makes power is CFM. So if anyone has experience with upgrading to a 16G from a 14B please help me out really quick.

If you were to take two completely stock 1G engines, which turbo would be pushing more CFM by 2500 RPM, a 14B or a 16G?

Sorry if my question seems a bit noobish, but I haven't found the ansewer through research.
Thanks,
R.J.

 

[big_eskimo]

Perhaps I should rephrase the question. Will a 16G pull as hard as a 14B at 2500 RPM on a stock 1G engine?

 

[Sharkcus]

So if anyone has experience with upgrading to a 16G from a 14B please help me out really quick.

They are very similar turbos. The both use the same compressor housing and close to the same turbine housing (6cm vs. 7cm) but you can port your 14b housing out to 7cm.
They both use the same exhaust turbine wheel and a nearly identical center cartridge. The big difference lies in the compressor wheel.

In other words, as far as installation is concerned, it will fit in EXACTLY like your 14b did. No modifications necessary.

I had both a 14b and a 16g on my car. I couldn't tell the difference in spool times, but the 16g did pull a lot harder at the same boost levels. I hope that helps.

 

[big_eskimo]

They are very similar turbos. The both use the same compressor housing and close to the same turbine housing (6cm vs. 7cm) but you can port your 14b housing out to 7cm.
They both use the same exhaust turbine wheel and a nearly identical center cartridge. The big difference lies in the compressor wheel.

In other words, as far as installation is concerned, it will fit in EXACTLY like your 14b did. No modifications necessary.

I had both a 14b and a 16g on my car. I couldn't tell the difference in spool times, but the 16g did pull a lot harder at the same boost levels. I hope that helps.

So I take it that despite the 16G takes a little longer to spool, it still flows more CFM at lower boost levels than the 14B? Thus creating more power at any RPM (including lower RPM's) even though it isn't pushing the same PSI at the lower RPM's? Could someone please confirm this?
Thank You,
R.J.

 

[Sinclair159]

I think i would have to point you in the direction of the small 16g... do some searches and look around, alot of people have had TUNS of succes on this turbo... great spool up, and makes alot of power from 15-20 psi on a mild setup...

 

[sower23]

When I first put on my new head, I put the old 14b back on plus a fmic, injectors maf and maft with stock exhaust, and an air intake with kn. That turbo spooled so fast and pulled so hard it would nearly pull me off the road. Granted this was at like 20 psi but still that little turbo is capable of a lot. Project goodwill ran below 11 sec quarter mile with it and supporting mods. I just can't imagine what it would have been like if I had my 3" exhaust on there too. Basically, your turbo is only as good as your supporting mods. When I did finally put the 57 trim (50lbs) on, it felt a ton slower than the 14b cause i was still on the stock exhaust (exhaust on serious backorder). Sooo I guess what Im trying to say is any of those turbos will suffice for you but the 14b will be quicker to spool up on less supporting mods. I would definitley invest in the fmic instead of the smic it just looks bad ass plus when, not if, (modding is a disease) you want to upgrade your turbo, you will need a fmic. Go big first and save some money!

 

[dsm-onster]

OK,
So after some furter research and getting more understanding of turbo's I have a new question. So apparently reaching full spool, and hitting a certain PSI has no real weight, what makes power is CFM. So if anyone has experience with upgrading to a 16G from a 14B please help me out really quick.

If you were to take two completely stock 1G engines, which turbo would be pushing more CFM by 2500 RPM, a 14B or a 16G?

Sorry if my question seems a bit noobish, but I haven't found the ansewer through research.
Thanks,
R.J.

NO, no, no. So the F&%$ what if your turbo can flow 1,000,000 cfm?!!! It is about how much your engine flows. If you engine can only accept a certain amout of flow per revolution then there is no need upgrading to turbos that can deliver more. From personal experience, the SMALL 16g is all that is needed for a stock long block (stock cams, stock bore & stroke) and stock rev limit.

You will do well with a 14b or a 16g (much, much better for higher boost and real horsepower for stock cams on the stock ecu). An evo3 is a good upgrade if you're scared of boost and need more flow because you've upgraded cams and raised your rev limit (increased flow). The evo3 is not as efficient as people thing at high boost.