B18C turbo

Time has come for me to upgrade the turbo I have on my car at the moment. It is just too small for what I am after now, although the extremely quick spool is a lot of fun.

I am looking at a GT3071R with a .86 rear-
http://www.turbobygarrett.com/turbob..._700382_20.htm

I would like it to be bolt on and this should fit straight up with only having to adjust the intake pipe. I am looking at staying with 8-10PSI and not looking to build the motor for a while yet although I think this should give plenty of room to move.

I know that a lot of you B16 guys are running the 2871R with a .86 rear so I think that this should give me that bit more flow for the B18C.

This turbo I am suggesting does not seem to come up much in discussion, so what are its compromises? I really do not want to change the manifold and downpipe flanges either as it is just more mucking around.

discussion, opinions, suggestions are welcome.:thumbsup:

That turbo will flow plenty for what you want to do with it, i would keep with the .63 rear

i have a 3071R turbo and boosts up about 4k on an SR20 so similar time on a B18 seeing that the capasicity is smaller same or longer time and that is with a .63 housing and larger trim.

i would stay the smaller housing but with that front you wont run out of puff on that boost level and also consider the turbos effecincy range and 8-10psi on a 30 with .86 isnt in it.

IMO stay with the disco potato if you want to run low boost

Quote:

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Originally Posted by lookingforboost

That turbo will flow plenty for what you want to do with it, i would keep with the .63 rear

i have a 3071R turbo and boosts up about 4k on an SR20 so similar time on a B18 seeing that the capasicity is smaller same or longer time and that is with a .63 housing and larger trim.

i would stay the smaller housing but with that front you wont run out of puff on that boost level and also consider the turbos effecincy range and 8-10psi on a 30 with .86 isnt in it.

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dont take this the wrong way..................but u can not compare an sr20 with 8.5 comp compared to a b18c with 11.1 comp..........

the difference in spool time is rediculous and if the honda tuner knows how to tune a honda, with plenty of ignition timing a larger turbo will come onto boost just as quick as the smaller unit..................

b18c needs a minimum gt30 (500hp) roller...............and 0.82 rear........

good luck with it all...............i have done it before and would never look back from a t28 ...

pm me if u want any help

I know you have been a champion of the bigger turbos in the past EVAQ plus had very good results.

ATM my 2860 only has the .64 rear and it is way too small, power is limited at the top end to identical whether I run 8 or 10 PSI. throughout the rev range it is about 8kw more on 10PSI but then tapers off. I have attached a dyno read for a bit more info

http://img33.imageshack.us/img33/9025/scan0002oa.jpg

when i had my t28 it also had 0.86 rear and was still way too small, u will even get away with a 2876r which will bolt to ur manifold and dump pipe and still have the ability to rev and make power a lot longer and later in the rev range.... ;)

don't go the 2876, its very laggy without the benefit of the power you could get.
The GT3071r is good for a b18, and alot of people recommend them for a dragcar or hi-power car.

If you want abit more power i'd change to the .86 rear for the 2860 and you will find it may be that extra power you want.

Quote:

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Originally Posted by Limbo

If you want abit more power i'd change to the .86 rear for the 2860 and you will find it may be that extra power you want.

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I would try upgrading to .86 exhuast housing as well, also what exhaust size are you running atm?

as i have mentioned before..............
here is my graph comparison to t28 with 0.86rear
and gt3076r with 0.82 rear....
http://i287.photobucket.com/albums/l...race-power.jpg

GT2860RS is quite abit larger than a GT28R (which is actually a GT2560R)
Rem that the 2860RS has T3 internals and flows alot better.
Out of the Garrett range the 2860rs is one of the most efficient in its range, it also shares the same exhaust as the GT2871r & GT2876r

Try the rear first its cheaper than a whole new turbo setup.
With the GT3071r to make the most of it its best to get it with a T3 flange rather than the T28 to reduce restriction

P.S if you wanna get rid of the smaller rear let me know i don't mind having a spare and i wanna see how it handles with the smaller rear.

would be a good swap for you limbo..both get the benefits.

another thing to remember guys, is that a b18c has more static comp than ur b16's which u have all had plenty of experience with, but when u have more comp, its another ball game, dont be afraid to run a gt30, as my graph shows, there is a slight section in the graph where the gt30 is showing less power than the gt28, however, it isnt even noticable when driving.......id love to take all u guys for a drive to compare with ur super responsive gt28's.......

trust me when i say mine aint laggy..........

^^ he makes a good argument.:)

Limbo, I will keep the offer in mind, thanks.

might have to enquire on how much it would cost to upgrade the rear and see how that goes, would be an interesting comparison. I think that I am still more of a mind to just change the whole thing though.

I am running a 2.5 inch exhaust all the way through at the moment.

Quote:

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Originally Posted by mooshie

^^ he makes a good argument.:)

I am running a 2.5 inch exhaust all the way through at the moment.

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thanks,

and u need to change ur exhaust to a full 3 inch system................the more flow and less back pressure the better......

Quote:

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Originally Posted by mooshie

might have to enquire on how much it would cost to upgrade the rear and see how that goes, would be an interesting comparison. I think that I am still more of a mind to just change the whole thing though.

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If you do swap to a bigger turbo and decide to sell your disco potato shoot me a PM

true i forgot to factor in the comp ratio but the Type R and the VTiR has different comp ratios right? i am not to sure?

yeah type R is quite abit higher

Im currently using a gt30 in a b18c blacktop, it spools at about 2100rpm.
Being as i've never tried a t28 cant say which is better, but it's currently making 216hp at 7psi.

P.s. Arent the T28 and T3 flanges different may need an adapter or new manifold?

dam that's a quick spool for a gt30 wat rear are you running?

yeah the gt28 & gt3 have different flanges

I think it's a .86 but got a really short log manifold so that may help.

i dun think it helps that much, unless your like not running an intercooler?
Even luke with his log doesn't spool that fast. He doesn't hit full boost until 4.5k rpm

dam makes me think if i should have got the gt30 instead of my gt2871r when i did my last rebuild/upgrade.

yeah but i would have thought the GT30 would have been a later spool.
Maybe he's got a small rear housing

The GT3071r is available in a T28 housing, it is the largest you can go before going up to the T3 style.

swooshek: 2100 is a very low spool. Is that when it starts up? mine currently starts to spool up at about that and is full boost by about 3500rpm.

you dont happen to have a dyno print out do you?

http://i198.photobucket.com/albums/a...ooshek/fcy.jpg

Interesting...

I plotted swooshek's dyno onto a similar one that I had when the car was first tuned on a similar dyno.
allowing for the shift in the graphs (move the pencilled line about 3/4 of a square to the left) they look quite similar, although I am running about 1-1.5PSI more on average throughout the rev range.

http://img24.imageshack.us/img24/4862/gt30vsgt2860.jpg

My car still had a 2.25 inch exhaust at this time.
Interesting to compare this chart to the one on the first page as well, that one is about 10kw higher right through the rev range after re-tuning for the new 2.5inch exhaust.

different days, different dynos= 134kw max as compared to this 157kw

just to put your pic on here instead of the link, hope you don't mind-
http://img27.imageshack.us/img27/8356/swoosheksgt30.jpg

BTW, 216hp is approximately 161kw

Quote:

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Originally Posted by mooshie

just to put your pic on here instead of the link, hope you don't mind-
http://img27.imageshack.us/img27/8356/swoosheksgt30.jpg

BTW, 216hp is approximately 161kw

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That's a bit low for a B18 :o

I'm making 202HP ATW on only 8psi on my SiR 2 B16A 2.5inch exhaust
http://www.scruffie.com/luke/car/151.3kw_psi.jpg

you took the words out of my mouth luke...

I wanted to say the same but didnt want to put the guy down. I was getting around 161kw on 8psi on a very rough tune.

im on 168kw atm with my 10psi tune which is very rough and is lacking a new pressure sensor. It was almost a "this will do for now" tune.

Quote:

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Originally Posted by FastFwd

you took the words out of my mouth luke...

I wanted to say the same but didnt want to put the guy down. I was getting around 161kw on 8psi on a very rough tune.

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Might be his tune, A&F mix is all over the show

Most guys with boosted B18's are making about 170kw 7-8psi..

FF - my car seems to hold 10psi fine, need another map sensor?

Quote:

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Originally Posted by Limbo

FF - my car seems to hold 10psi fine, need another map sensor?

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Nah nah we were tuning it for 22-24psi and it was having issues couldnt figure it out and the only psi that wasnt making my ECU read randomly was 10psi or under so we chucked it at 10psi roughly enough for me to come back after ive figured out the issue. In the end i found that my stock map sensor only reads upto 10psi which i didnt know. Havent got another sensor yet and havent retuned it. So the 10psi tune i have atm was just rough and i got 168kw thats all i was trying to say.

You want to give me that map sensor you got in your toolbox :)

Quote:

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Originally Posted by FastFwd

Nah nah we were tuning it for 22-24psi and it was having issues couldnt figure it out and the only psi that wasnt making my ECU read randomly was 10psi or under so we chucked it at 10psi roughly enough for me to come back after ive figured out the issue. In the end i found that my stock map sensor only reads upto 10psi which i didnt know. Havent got another sensor yet and havent retuned it. So the 10psi tune i have atm was just rough and i got 168kw thats all i was trying to say.

You want to give me that map sensor you got in your toolbox :)

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Stock will handle about 12ish

Na give me your MAP Hao :p

mine got to 11psi is think and even on 11 is was fairly safe but not 100%.

Dont know if different ECU's react differently with the stock map sensor or not.

nah you need to upgrade the map sensor when going over 10PSI otherwise your readings go crappy, doesn't matter what ECU

FF - nah i'm holding on the the 3bar sensor, its a Bosche so should be decent in case i wanna go higher. Been told they are hard to come by.

Quote:

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Originally Posted by Limbo

nah you need to upgrade the map sensor when going over 10PSI otherwise your readings go crappy, doesn't matter what ECU

FF - nah i'm holding on the the 3bar sensor, its a Bosche so should be decent in case i wanna go higher. Been told they are hard to come by.

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My D turbo held 11-12psi on stock MAP

Yeah im looking for a good 3bar sensor... Im not in any rush.

look on ebay man, i got a GM one for like 60 bucks i think

just got my 3 bar sensor :)

the map sensor you guys have is it generic or was it made to fit b series?

the one i got was off a b18c

just to get this back on track, here are a couple of comparisons-
http://img190.imageshack.us/img190/3...20turbt.th.jpg
http://img190.imageshack.us/img190/1...71turbt.th.jpghttp://img35.imageshack.us/img35/1720/7433471turbt.jpg
http://img35.imageshack.us/img35/339...82320turbt.jpg


as you can see the rear on the GT30 has a fair bit more flow than the GT28 having said that, the difference between the .64 and .86 on the 28 is quite big as well, maybe this would be enough?


http://img38.imageshack.us/img38/452...12compt.th.jpg
http://img38.imageshack.us/img38/12/...20compt.th.jpg
http://img38.imageshack.us/img38/172...71turbt.th.jpg
http://img38.imageshack.us/img38/339...20turbt.th.jpg

Personally, I wouldnt get the GT3071R with a T28 style exhaust housing, it is more efficient with the .63 T3 housing

agreed ^^^^

The T28 flange adds too much restriction on the GT3s

what do you guys think would spool faster,

gt2871r with .82 t3 housing

or gt3076r with .63 ar t3 housing

this on a b16a2 with ~8.6:1 CR

i ask this because i went from .63 t3 -> .82 t3 on my gt2871r and it gains full boost over 1000 rpm later now. was around 4250, but now it seems 5500 or even a little later, i wonder if the housing is just too big for the turbine.

although my powe rband now is much more meaty, i wonder if a gt3076r would net me similar spool, but more power from a better efficency part of the compressor map + later choking point from the turbine outlet.

this is for 20psi on pump fuel btw

hard to say cos i've never seen the .82 rear on the gt2871r.
I know on my gt2871r T28 with .86 rear , it starts to spool at about 2,300k, then hits 10PSI at about 4,500k.

Haven't seen a gt3076 on a b16, but it would be at least another 500rpm later

Judging by my compression and a 8.6 i'd say it would take another 250 to 500rpm more to spool up + 500 or so to boost to 20PSI. Once you get about 6PSI the boost will jump very fast.

that's my best guess

with the 30 you would get full boost by about 5000rpm or a touch later but would hit a lot harder once on boost :)

Quote:

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Originally Posted by Limbo

agreed ^^^^

The T28 flange adds too much restriction on the GT3s

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given that I do not want to have to change out flanges and alignment on the dump etc though, the T28 rear on the GT 30 is still going to flow more than the 2871R.

at the moment I am thinking just change out the rear on my existing turbo for a .86 as previously suggested. should only run me about $450 plus tuning

Quote:

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Originally Posted by mooshie

given that I do not want to have to change out flanges and alignment on the dump etc though, the T28 rear on the GT 30 is still going to flow more than the 2871R.

at the moment I am thinking just change out the rear on my existing turbo for a .86 as previously suggested. should only run me about $450 plus tuning

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Yeah I'm running the 0.86 rear and its seems to work well

Quote:

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Originally Posted by lookingforboost

with the 30 you would get full boost by about 5000rpm or a touch later but would hit a lot harder once on boost :)

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looks like i should swap out the .82ar t3 rear gt2871r for a gt3076r with .63ar housing.

sounds like boost will be similar or maybe slightly better, with much more potential as well :P i gota quote for 1350 US$ delivered to my house maybe i shoudl take it up... hmmm

True but you loose the potential of the T3 by not changing the exhaust flange

Quote:

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Originally Posted by mooshie

given that I do not want to have to change out flanges and alignment on the dump etc though, the T28 rear on the GT 30 is still going to flow more than the 2871R.

at the moment I am thinking just change out the rear on my existing turbo for a .86 as previously suggested. should only run me about $450 plus tuning

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Just a quick question while we are on the topic, would a GT35R with a .63 rear housing be too big for a low boost B18C2 application?

Quote:

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Originally Posted by IEVAQ8

as i have mentioned before..............
here is my graph comparison to t28 with 0.86rear
and gt3076r with 0.82 rear....
http://i287.photobucket.com/albums/l...race-power.jpg

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No offence bro, but the graph shows that you're pulling torque more than a truck.

That is torque at the wheels in 4th gear

shit, never seen that before on any of my dynosheet. Do people mostly measure at the flywheel.

all dynos are measuring at wheels not flywheel. Only manufacturers measure at flywheel.

Normally you loose about 20-25% thru drivetrain, sometimes more depending on the car

Quote:

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Originally Posted by kccord

No offence bro, but the graph shows that you're pulling torque more than a truck.

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no offence taken.......

but as explained below, its all measured at the wheels not flywheel...

Simply put, gearing multiples torque. If you look at the dyno printout it says ratio = 4.940 so to calculate derived torque it would be 1484 / 4.94 = 300Nm which is still a good amount of torque

bang on, thanks for clarifying.