Resolved Forced Performance Big 28?

[pboglio]

Guys that are saying a T25 turbine housing is small but a 7cm housing is O.K. should go and lay them side by side. Thats right, a T25 .49 A/R turbine housing is BIGGER, physically bigger than a 7cm^2, both in measured volute area "A" and overall radius "R". It is closer in volute area to an 8cm^2 turbine housing actually. T28 also has a BIGGER stock wastegate orifice and valve than any of the stock Mitsu 16g turbos.

Sure, the T25 compressor cover is small. Ever see the inside of a TD05H compressor cover? There is virtually NO diffuser left beyond the compressor wheel, almost none. If the T28 compressor is inefficient in a T25 compressor cover, so is a 16g wheel in a TD05H compressor cover for the same reason. Seems to work just fine in practice, I've owned and have run both turbos in question. They are so close in performance its like splitting hairs.

Fact, a Forced Performance customer ran 119 mph on the FPbig28. Dennis Grant dynoed 348 w.h.p. on a FPBig28 and is kicking ass in auto-x with one. In practice they have few downsides other than they don't make 400 w.h.p. Maybe guys with their 50 trims are pissed because they can't run the numbers they should or their turbos are self-destructing left and right. Enjoy.

 

[FWD98GST]

pboglio,

I agree... For a daily driver, the big28 just fits fine for a 2g... If you plan to go bigger you still have to do the upgrades to motor and drivetrain... Just for me, the big28 does enough and has the daily driver capability with some punch... Also, when it comes to smog for a 2g, visual will pass

Just remember, Gas prices are going up :thumbdown

 

[tramp]

I'd go on what others have done with a big28 as a yardstick. If I failed to reach that mark I wouldn't blame the turbo.
For a responsive "plug n play" $600 turbo it packs quite a sting imo.
A good turbine wheel goes a long way in a 'small' turbine housing, eg. green, red, 20g.
Just as a comparison, a *full weight* nissan 240sx hatch went 12.2@122mph! Crappy 2.X 60ft spinning drag radials going sideways. Did it on a *bone stock* sr20 with a jwt ecu (notoriously rich & weak timing). Stock sr t25 upgraded by FP to a big28. I'm sure that car has solid 11s in it had the owner applied more 'drag strip' effort. Car dyno'd 325whp/335tq. Lots of sr with far more expensive turbos don't hit 335 ft-lbs. Not saying its even close to the best drag racing turbo, but its not a bad bolt-on deal at all for the money.
That same turbo made 341whp/370tq when "tuned" on an sr20. Very close to the DG car, eh. Impressive torque figures that make for a fun street ride that can hold its ground against most things.

 

[GSX99Ca]

well thx for replys from every1. well like i said im just going for a street/daily driver turbo (not going all out) just enough to beat on some higher classed turbo'd cars and v8's, Still good things have been said about FP Big 28 but also the EvoIII Big 16g have been mentioned alot. I have a GReddy FMIC, just waiting to get new turbo before it gets put on. I was also curious if you guys think i should buy a new O2 housing or just have mine ported, same about the exhuast manifold. and when i get turbo i will be getting new injectors. SO its narrowed down to 2 turbo's now, so what you guys think from experience........EvoIII Big 16g or FP Big 28????? Thx again for responses

 

[GSX99Ca]

o ya, im wanting to get anywhere from 350-380 whp.

 

[Generation X]

Guys that are saying a T25 turbine housing is small but a 7cm housing is O.K. should go and lay them side by side. Thats right, a T25 .49 A/R turbine housing is BIGGER, physically bigger than a 7cm^2, both in measured volute area "A" and overall radius "R". It is closer in volute area to an 8cm^2 turbine housing actually. T28 also has a BIGGER stock wastegate orifice and valve than any of the stock Mitsu 16g turbos.

Sure, the T25 compressor cover is small. Ever see the inside of a TD05H compressor cover? There is virtually NO diffuser left beyond the compressor wheel, almost none. If the T28 compressor is inefficient in a T25 compressor cover, so is a 16g wheel in a TD05H compressor cover for the same reason. Seems to work just fine in practice, I've owned and have run both turbos in question. They are so close in performance its like splitting hairs.

Fact, a Forced Performance customer ran 119 mph on the FPbig28. Dennis Grant dynoed 348 w.h.p. on a FPBig28 and is kicking ass in auto-x with one. In practice they have few downsides other than they don't make 400 w.h.p. Maybe guys with their 50 trims are pissed because they can't run the numbers they should or their turbos are self-destructing left and right. Enjoy.

Agreed! To add to your post Dennis Grant also made those numbers without the aid of cams as well.

 

[pboglio]

o ya, im wanting to get anywhere from 350-380 whp.

Here's the maxflowrates @ 60-65% compressor efficiency based on existing maps:

Garret 62 trim (FPBig28):_37-38 lb/min (~370-380 crank h.p.)
EVO 8 16g:_____________42-43 lb/min (~420-430 crank h.p.)
Mitsu 20g:______________46-47 lb/min (~460-470 crank h.p.)
Garrett 50 trim:_________48-50 lb/min (~480-520 crank h.p.)

With 100% V.E., 2.0L motor, 55*F I.C. exit temps, 7000 rpm limit, you would "only" flow 44.7 lb/min (~380 w.h.p.) on 20-21 psi. That means you can get your 380 w.h.p. if you have a turbo that can supply 44.7 lb/min at 20-21 psi on its compressor map & not pose an ounce of restriction on the exhaust side. That turbo does not exist. So you need to run a bit more boost to account for lower V.E. Running 21 psi is almost pushing it on 93 octane, let alone 91 octane.

For 91 octane pump gas 380 w.h.p., forget the FPBig28, EVOIII 16g, or the 20g. They all use a fairly small turbine wheel & turbine housing that kills V.E. at high rpm. I'd have to agree that a 50 trim has the best chance of flowing 380 w.h.p. on 91 octane pump gas because of its higher turbine V.E. capability and its higher compressor output.

 

[GSX99Ca]

Makes sense to me, thx for your post.

 

[Jaraxle]

Guys that are saying a T25 turbine housing is small but a 7cm housing is O.K. should go and lay them side by side. Thats right, a T25 .49 A/R turbine housing is BIGGER, physically bigger than a 7cm^2, both in measured volute area "A" and overall radius "R". It is closer in volute area to an 8cm^2 turbine housing actually. T28 also has a BIGGER stock wastegate orifice and valve than any of the stock Mitsu 16g turbos.

Sure, the T25 compressor cover is small. Ever see the inside of a TD05H compressor cover? There is virtually NO diffuser left beyond the compressor wheel, almost none. If the T28 compressor is inefficient in a T25 compressor cover, so is a 16g wheel in a TD05H compressor cover for the same reason. Seems to work just fine in practice, I've owned and have run both turbos in question. They are so close in performance its like splitting hairs.

Fact, a Forced Performance customer ran 119 mph on the FPbig28. Dennis Grant dynoed 348 w.h.p. on a FPBig28 and is kicking ass in auto-x with one. In practice they have few downsides other than they don't make 400 w.h.p. Maybe guys with their 50 trims are pissed because they can't run the numbers they should or their turbos are self-destructing left and right. Enjoy.

EVO 16g
1.903 C - inducer
2.675 C - exducer
1.935 T-exducer
2.205 T-major

Largest T-25/T3 hybrid (that I could find T-28 published since FP magical turbo is area 51 top secret)
Found here: http://www.turbofast.com.au/balmid.html
1.86 C - inducer
2.37 C - exducer
1.86 T- exducer
2.09 - major

Just 2 weeks ago I had my T-25 and Evo 16g side by side. The inlet and outlet of the turbine housing was a no-compare. Where are you getting that T-25 turbine housing size comparison information from ?
What is the size of the T-25 wastegate ?
Evo 16g compressor inducer and exducer are larger, and so is the compressor cover. Perhaps the relationship is similar to a T3 in a T-25 housing, but overall larger. However, from my research I settled on a evo 16g due to the turbine housing and small T2 shaft size.

-Jaraxle

 

[big green]

It depends what you are looking for in a car. For my goal (300whp) the FP big28 was the way to go. I really like the turbo and cant wait to turn up the boost

 

[pboglio]

EVO 16g
1.903 C - inducer
2.675 C - exducer
1.935 T-exducer
2.205 T-major

Largest T-25/T3 hybrid (that I could find T-28 published since FP magical turbo is area 51 top secret)
Found here: http://www.turbofast.com.au/balmid.html
1.86 C - inducer
2.37 C - exducer
1.86 T- exducer
2.09 - major

Just 2 weeks ago I had my T-25 and Evo 16g side by side. The inlet and outlet of the turbine housing was a no-compare. Where are you getting that T-25 turbine housing size comparison information from ?
What is the size of the T-25 wastegate ?
Evo 16g compressor inducer and exducer are larger, and so is the compressor cover. Perhaps the relationship is similar to a T3 in a T-25 housing, but overall larger. However, from my research I settled on a evo 16g due to the turbine housing and small T2 shaft size.

-Jaraxle

Yes, T25 inlet is 2.1" and 16g is 2.365" or so. That gets ported out almost immediately, its also the biggest portion of the turbine housing. It has minimal affect on turbine backpressure and spoolup capability. Take a caliper and measure both housings.

Here's a few numbers for comparison:

6cm turbine housing outer dia: 4.600"
7cm turbine housing outer dia: 4.600"
T25 turbine housing outer dia: 4.900"

6cm volute dia: 1.100"
7cm volute dia: 1.171"
T25 volute dia: 1.185" (I said close to a 8cm, I was wrong, only a bit bigger than a 7cm)

6cm/7cm wastegate valve dia: 1.175"
wastegate orifice dia: 0.900"

T25 wastegate valve dia: 1.280"
wastegate orifice dia: 0.965"

Like I said, the T25 turbine is bigger. It looks huge inside and huge outside sitting next to the 7cm housing, you gotta look past the turbine inlet and look inside down deep. Once you lay them next to each other you go; What, can't be bigger, this thing is only a T25, what the hell? Take a caliper and measure both housings. I think I measured them like 6 times to make sure I wasn't seeing things.

 

[GSX99Ca]

so between the EvoIII Big 16g and the FP Big28, which would i be getting more power from. Whats both turbo's Max HP rating?? Thx

 

[GSX99Ca]

o and which is a better on the roll turbo (like freeway, or just getting up to speed on a roll)

 

[Thomas91169]

i too was in this same prediciment as you.

FP T28 Killer or Evo16g.

i said to myself since im in cali i must pass smog and visual, so the t28 would be the turbo of choice. till i met a guy with a evo16g and took a ride, and it kicked my ass so hard i bought one a week later and never looked back.

basically if you want another quick spooling turbo that will poke at the 300hp mark, lay waste to most "tooner civics and tegs", but leave you yearning for more, the t28 is for you. if you want a turbo that can take you deep into the 300hp range and laugh at stangs, camaros, evos, sti's and srt4, and still be dam good at daily driving, the Evo16g is for you.

and ive came to a conclusion. turbo swaps are like marajuana. its a gateway drug. you tell yourself that this is gonna be it but once the high is done, you want more(as in more boost), and to get a better high(boost) you need to get a better drug(bigger turbo), and the better drug costs more and comes at a price, risk of cancer, heart attack(crankwalk, blown trannies). we dsmers seriously need rehab clinics across the US.

 

[Thomas91169]

the evo16g max hp rating is somewhere around the 400-420hp range, a t28 is somewhere around the 320-350range on a good day.

both turbos will work very well from a roll, the t28 will spool alot faster, which on a fwd would hurt cause it could induce wheelspin, but on a awd a faster spool would benefit it. but the evo has more top end and spools at around 3500 and would be better for FWD, though a AWD would benefit from its top end on a roll also to compensate for the awd drivetrain loss.

 

[GPTourer]

Yeah, I thought the same thing when I had my T-25 out and it was laying next to my EvoIII, my upgrade didn't seem "bigger" at all. But once it was installed and tuned all worries went away.

I was very close to picking the T-28, but decided it just didn't have the track record of the B16G, and am glad I didn't get it. Seems like I read more then enough disappointing reviews of it then I did of the EvoIII.

First off i want to thank you guys for the reply about the S20G, and made my mind up and decided not to get it.

What did you mean by S20G? A SBR 2G20G or a Hahn Super 20G? Those turbos have loads of controversy and I avoided both for probably the same reasons you did, but a real TD06H-20G should get you a lot closer to 400whp then a T-28 or even EvoIII ever will.

 

[heavyD]

I think the lag of the T28 is just about the limit for me, but thats me.

Are you serious? My FPT28 spools nearly as fast as the T25. If you think that is the limit of lag for you, maybe you should go back to N/A engines. This is the "Engine Performance" forum last time I looked and you are whoring it up with your "lag" talk like it shouldn't exist in a turbocharged engine. My FPgreen takes only about 800 rpm longer to spool up than my T28 and it kicks in and pulls like gangbusters all the way to redline unlike the T28 which starts to fall off after 6000 rpm and I had cams with my T28!!!

I have the feeling you have never been in a DSM with a properly set up 50 trim. You can post all the dimensions, specs, maps, you want but what really matters is driving the cars and feeling the difference for yourself. Until you do, I suggest you quit putting down larger turbos.

When you consider cost vs performance, the T28 is a poor choice for a person looking for a performance upgrade. End of story.

 

[DR.Spock]

Are you serious? My FPT28 spools nearly as fast as the T25. If you think that is the limit of lag for you, maybe you should go back to N/A engines. This is the "Engine Performance" forum last time I looked and you are whoring it up with your "lag" talk like it shouldn't exist in a turbocharged engine. My FPgreen takes only about 800 rpm longer to spool up than my T28 and it kicks in and pulls like gangbusters all the way to redline unlike the T28 which starts to fall off after 6000 rpm and I had cams with my T28!!!

I have the feeling you have never been in a DSM with a properly set up 50 trim. You can post all the dimensions, specs, maps, you want but what really matters is driving the cars and feeling the difference for yourself. Until you do, I suggest you quit putting down larger turbos.

When you consider cost vs performance, the T28 is a poor choice for a person looking for a performance upgrade. End of story.

i agree, but the T28 is still a nice turbo for what it is. and yes lag is very overrated, DOWNSHIFT!! im running an FP3052 and i think is just right. perfectly streetable. i got it instead of the 3065 thinking the 3065 will have to much lag but no i shoulda went ahead an got the FP3065. but im perfectly happy with my 3052. ive been in a 1g with a GT35 turbo and the thing is huge but because his car is tuned and set-up right the lag is not bad at all.

 

[pboglio]

Are you serious? My FPT28 spools nearly as fast as the T25. If you think that is the limit of lag for you, maybe you should go back to N/A engines. This is the "Engine Performance" forum last time I looked and you are whoring it up with your "lag" talk like it shouldn't exist in a turbocharged engine. My FPgreen takes only about 800 rpm longer to spool up than my T28 and it kicks in and pulls like gangbusters all the way to redline unlike the T28 which starts to fall off after 6000 rpm and I had cams with my T28!!!

I have the feeling you have never been in a DSM with a properly set up 50 trim. You can post all the dimensions, specs, maps, you want but what really matters is driving the cars and feeling the difference for yourself. Until you do, I suggest you quit putting down larger turbos.

When you consider cost vs performance, the T28 is a poor choice for a person looking for a performance upgrade. End of story.

I'll make recommendations to people when and where I choose to. If you've got good experiences with 50 trims or the like, post them of course, this is a forum afterall. BUT, your position sounds pretty weak when you need to tell other people NOT to post their opinions. Don't like my posts, hit page down. Fair enough. I'd be more than happy to give a ride in my "slow" T28 AWD to a DSMer in the Chicagoland area, just shoot me an e-mail. Better wear a neck brace though

Please, go back and read where the original poster asked for a 350-380 w.h.p. requirement. Now, read my response VERY carefully. Thats right, I RECOMMENDED the 50 trim because it has the compressor AND turbine section that would get him there on 91 octane.

 

[heavyD]

Fair enough. I'd be more than happy to give a ride in my "slow" T28 AWD to a DSMer in the Chicagoland area, just shoot me an e-mail. Better wear a neck brace though

Why would I need to ride in your car? I have a T28 also and I know what it's capable of. I never said it was a slow turbo but compared to my FPgreen it sure does feel slow.

I look at it this way. For every person that says they love their T28, you have a person who is disappointed. That's only about 50% satisfaction which is poor. Ask how many people are disappointed with their EVOIII 16G, I bet that you won't find too many disappointed responses. That is why I will always recommend an EVOIII over a T28. I feel comfortable voicing my opinion about the T28 because I have one. You can voice your opinion also but please don't give advise about turbo lag on large turbo's when you don't even have experience with them.

 

[daren_p]

well thx for replys from every1. well like i said im just going for a street/daily driver turbo (not going all out) just enough to beat on some higher classed turbo'd cars and v8's, Still good things have been said about FP Big 28 but also the EvoIII Big 16g have been mentioned alot. I have a GReddy FMIC, just waiting to get new turbo before it gets put on. I was also curious if you guys think i should buy a new O2 housing or just have mine ported, same about the exhuast manifold. and when i get turbo i will be getting new injectors. SO its narrowed down to 2 turbo's now, so what you guys think from experience........EvoIII Big 16g or FP Big 28????? Thx again for responses

My personal preferance would be to go with the EVOIII. It only takes a couple hundred rpms longer to spool compared to the t28 but it has more hp potential and flow better in the top end. For your exhaust manifold, just get it ported & for the o2 sensor you could get a nice tubular one but if you have other things you'd like to buy, I wouldn't give the o2 sensor priority. Just port your stock one, making the wg port as large as you can to prevent boost creep. Also good idea to port the turbo before you install it, will give you quicker spool & better top end

 

[DSMeclipse4G63]

Volumetric efficency has to do with the engine not the turbo. Every turbo engine has close to or 100% efficency because it is being force fed, Volumetric efficieny is a percentage a egine can fill the combustion chamber or cylinder on the intake stroke. On a n/a motor the vacuum can only suck so much air making a typical n/a engine 76% efficient. meaning it can only fil 76% of the cylinder on the intake stroke, turbos feed pressurized air or compressed air into the cylinder pushing alot more air into the cylinder filling the cylinder 100% on the intake stroke with denser air.

Pleas dont refer to volumetric efficiency as turbo efficiency, because they are COMPLETLY different. As far as contributing to the thread, I will say whats been said many times over the past few years: top end e316g, low end grunt t28. They both flow 550cfms, but the evo is a little more efficient and will flow more lbs/min of air then a t28 big or small. The t28 can produce good numbers and perofrm well and is a great street turbo for the average joe in a 2g, but when compared to a e316g its kinda hands down. The evo316g can produce around 400whp(I think sbr are the only people doing this right now), spools a little slower then a t28 but trust me the difference is so neglagible you wont be able to tell, and the cost is about the same. All in all with the e316g youll make more power and a little less torque(i.e 330hp 320tq just an example).

For what you want go for the evo316g, or if you can deal with slightly less power and want a easier install(16gs install on a 2g aint that bad trust me ) go for the t28. either one youll be happy.

 

[JiveMasterT]

look, if you're happy with mid 13s on your DD, then go with the fp28, if not, then go bigger.

You can always get a bigger turbo and run lower boost until you have all the supporting mods. I was considering an fp28, but ive since changed my mind to the fp green. I dont mind downshifting when I need to pass someone on the highway... i mean, whats so hard about rev matching your down shifts, flooring it, getting around the person and then up shifting again?

For me I am going to do all of the supporting mods before I put in the green. I am going to be driving this car every day to work and school in winter and summer, and im going to run it at the track in the summer. I have stock internals as well. I'm not saying you need to get a green, but I am saying that if you feel you are going to want to go bigger down the road, then do so now and just turn up the boost when you are ready.

I dunno, maybe it is just me, but at the track and on these forums I hear more people being disappointed with the fp28 than those praising it.

 

[slickster]

Are you serious? My FPT28 spools nearly as fast as the T25. If you think that is the limit of lag for you, maybe you should go back to N/A engines. This is the "Engine Performance" forum last time I looked and you are whoring it up with your "lag" talk like it shouldn't exist in a turbocharged engine. My FPgreen takes only about 800 rpm longer to spool up than my T28 and it kicks in and pulls like gangbusters all the way to redline unlike the T28 which starts to fall off after 6000 rpm and I had cams with my T28!!!

I have the feeling you have never been in a DSM with a properly set up 50 trim. You can post all the dimensions, specs, maps, you want but what really matters is driving the cars and feeling the difference for yourself. Until you do, I suggest you quit putting down larger turbos.

When you consider cost vs performance, the T28 is a poor choice for a person looking for a performance upgrade. End of story.

My point i was trying to make earlier.

 

[pboglio]

Volumetric efficency has to do with the engine not the turbo. Every turbo engine has close to or 100% efficency because it is being force fed, Volumetric efficieny is a percentage a egine can fill the combustion chamber or cylinder on the intake stroke. On a n/a motor the vacuum can only suck so much air making a typical n/a engine 76% efficient. meaning it can only fil 76% of the cylinder on the intake stroke, turbos feed pressurized air or compressed air into the cylinder pushing alot more air into the cylinder filling the cylinder 100% on the intake stroke with denser air.

Pleas dont refer to volumetric efficiency as turbo efficiency, because they are COMPLETLY different. As far as contributing to the thread, I will say whats been said many times over the past few years: top end e316g, low end grunt t28. They both flow 550cfms, but the evo is a little more efficient and will flow more lbs/min of air then a t28 big or small. The t28 can produce good numbers and perofrm well and is a great street turbo for the average joe in a 2g, but when compared to a e316g its kinda hands down. The evo316g can produce around 400whp(I think sbr are the only people doing this right now), spools a little slower then a t28 but trust me the difference is so neglagible you wont be able to tell, and the cost is about the same. All in all with the e316g youll make more power and a little less torque(i.e 330hp 320tq just an example).

For what you want go for the evo316g, or if you can deal with slightly less power and want a easier install(16gs install on a 2g aint that bad trust me ) go for the t28. either one youll be happy.

I'll assume your refering to my post, if not then I apologize. This is a point of semantics, I can't say your wrong. But V.E. and the Density ratio terms are treated SEPARATELY for supercharged engines in the calculation of engine power or the easier to obtain engine airflow value. Let me repeat, SEPARATE. Show me a text that shows them lumped together, I'll quote you the text that treats them as separate variables. Why is it separate? My opinion, its to isolate the effect of the N/A engine with its intake restrictions and manifold supercharging from the density ratio increase from mechanical supercharging. Why? Because you can change the density ratio with the turn of your boost controller, you can't do that with the V.E. term quite so easily. As an engineer you want to isolate variables so you can analyze and manipulate them.

Turbine and Compressor efficiency AFFECT the V.E. of the engine. I don't recall stating that they were the same thing.