Built b16, hi comp + boost ??

[kraiye]

Hi guys,

been reading bits n pieces about turbo b16's etc cause I've had the itch for boosted vtec for a while now.

currently running basically a built skunk2 head with pro1 cams & adjustable gears, ctr pistons, and 420cc injectors pressurised by 255lph Fuel Pump. All controlled by an S300 making 125 fwkw.

just after some experienced thoughts like what sort of boost should i put through this - if any. my aim is for a nice reliable daily (with a/c and p/s) that's occasionally tracked / stripped - and blows the doors of falcadors!!

I'm not looking at changing any current parts (including the 2.5" zorst) so what size turbo is suitable? Preferably one that will bolt up to a t28 flanged log mani. seems to be a lot of people recommending gt2871r's and gt30's... would they bolt straight on?

[Limbo]

10PSI is good, GT28R is good on daily drive(i currently have this making 162kwatw), GT28RS is good mid range (seen one @10PSI making 175kwatw), GT2871r is top end (haven't seen any good setups with this yet on a b16).

I'm gonna be trying the GT2876r, we'll see how it goes.
I think the T3 is abit big for a b16

[mooshie]

All the GT2xxxx turbos have same bolt pattern and will fit the same manifolds. GT3xxx Is diferent bolt pattern (and easier to find from the US)

[Limbo]

u can get the 2860,2871,2876 in a T3 flange also

[fatboyz39]

E85 with Boost is a winner

[SLOWEGG]

E85 with Boost is a winner

And a big turbo.

[kraiye]

Limbo, are you running hi comp pistons (CTR or better) with your 10psi?

[Limbo]

nope stock motor b16a2.
If you got a higher comp i'd go the GT2871r and take advantage of the hi-comp.
With the higer comp engines if your turbo is too restrictive it will cause the engine to ping

[Davo]

All the GT2xxxx turbos have same bolt pattern and will fit the same manifolds. GT3xxx Is diferent bolt pattern (and easier to find from the US)

not always, i had a GT3071R with a t28 .64 rear housing.
The 28 or 30 just defines the exhaust wheel size and the 60/71/76 generally defines comp wheel size.

personally i wouldnt be goin larger than a t28 on a high comp b16 motor simply cos the efficiency of anything larger than a t28 will require more boost to make it efficient.

[ZeForce]

The disco potato (GT2860RS) seems like a pretty good sized turbo for the B series engine. If I had more cash to spend, I definitely would have got one for my setup

[IEVAQ8]

personally i wouldnt be goin larger than a t28 on a high comp b16 motor simply cos the efficiency of anything larger than a t28 will require more boost to make it efficient.

the effeiciency range for any t28 is no more than 7000rpm.......

our hondas including kraiye's built b16 will by far be able to rev past 8000rpm...


dont be fooled kraiye, go one better and get a gt30, our hondas love them....
unless ur happy spend money on a turbo kit that will give u maybe 20-30kw more than what u have......i dont think that is bang for bux.....

if ur worried about lag, invest in a decent tuned length manifold and the lag....will be the same as a t28 with log compared to a tuned length mani with gt30...i have graphs to prove this as i spent the money 2twice to get where i am......

do some more research and speak to tuners that have done this work before adrian from toda is a perfect example as a tuner also james aka BLKCRX from revzone, also speak to people who have performed it on their cars already, deanno (DLO01), myself and there are many more..........

i happily drive my dc2r with stock 11.1 comp and gt30.....all day every day....

[ZeForce]

the effeiciency range for any t28 is no more than 7000rpm.......

our hondas including kraiye's built b16 will by far be able to rev past 8000rpm...

Compressor efficiency has very little to do with engine RPM.... it's based on pressure ratio and air flow which comes down to the amount of power you wish to make

[IEVAQ8]

Compressor efficiency has very little to do with engine RPM.... it's based on pressure ratio and air flow which comes down to the amount of power you wish to make

but with the efficiency range (air pressure) being not enough, u will notice it and feel it in the revs and how early the power will drop off,

the theory i have for building a honda, is very similar to building a rotary........
they love to rev (so do honda's) they responde exceptionally well to boost (as do hondas) and if tuned properly our hondas will last forever.....

dont be fooled with smaller turbos and too much lagg........

i think deanno said this once............

u cant really call it lag if the car was originally NA............the car will drive like it always did in NA form (off boost) and then u have boost............so its not really a down fall.......as the car wont and doesnt loose its charactaristics in the form of NA, just has the extra grunt with boost.

[Limbo]

The larger the turbo there will be lag.
The lag is the amount of time needed to produce enough puff to fill the turbo & piping.

As we have high comp & high revving the lag is generally reduced.

But your right, if your efficiency comes in too early you will out flow the turbo (happened to me also).
With the T28 it looks like at about 7krpm the turbo flattens abit. Only really noticable at 140km/hr

Also the T28/T30 generally is to indicate what flange you get.
There are your unusual ones which are T28s with T3 flange

[votek]

yeah but they are talking about lag in regards from a honda motor compared to sr20

[ZeForce]

Is the power dropping off in the higher rpms due to compressor efficiency or restriction in the exhaust housing? Generally, turbo "lag" is determined by the exhaust housing size. Smaller = quicker spool but will become restrictive in the high rpms. Larger = take longer to spool but with breathe better in higher rpm and hence make more power.

[Limbo]

yeah but they are talking about lag in regards from a honda motor compared to sr20

yep agree completely

[Limbo]

I think its restriction in housing in my case.



Is the power dropping off in the higher rpms due to compressor efficiency or restriction in the exhaust housing? Generally, turbo "lag" is determined by the exhaust housing size. Smaller = quicker spool but will become restrictive in the high rpms. Larger = take longer to spool but with breathe better in higher rpm and hence make more power.

[IEVAQ8]

Is the power dropping off in the higher rpms due to compressor efficiency or restriction in the exhaust housing? Generally, turbo "lag" is determined by the exhaust housing size. Smaller = quicker spool but will become restrictive in the high rpms. Larger = take longer to spool but with breathe better in higher rpm and hence make more power.

the only difference in the 2 setups is t28 rated at 400hp to gt3037s rated at 550hp cast log manifold - fullrace stainless tuned length manifold and 2.5inch exhasut to 3inch exhaust and internal 0.86rear housing to external 0.82 rear housing.............the power graph is the same and almost identical lag........

then u see the t28 drop off, where the gt30 love making power and revs

http://i287.photobucket.com/albums/ll147/ievaq8/avo-vs-full-race-power.jpg

[Limbo]

do you mind me asking which t28 you had previously? Looks similar to my T28R setup,
The GT2876r is rated at 480hp same as the GT3071r
hopefully it will respond similarly to your GT3071

[ZeForce]

do you mind me asking which t28 you had previously? Looks similar to my T28R setup,
The GT2876r is rated at 480hp same as the GT3071r
hopefully it will respond similarly to your GT3071

What sort of power are you chasing?

[Limbo]

about the 180kw atw mark. Only need abit more power, just something to easily pull me into the 12s.

[Davo]

IEVAQ8, the 2 setups your comparing are quite different. Using and internally gated t28 turbo with a .86 rear housing, smaller exhaust and log manifold to a externally gated .82 rear housing 3037 with larger exhaust and tuned length manifold. naturally with a smaller rear housing, external gate setup and bigger exhaust and tuned manifold you would reduce lag considerably.


i originally had a GT28R on my 180sx. with the exact same setup and only changed the turbo to a 3071R with the same Comp housing and same .64AR t28 rear housing, the turbo was laggier (not by much) but yes it definately did make more power.

on both setup were you running the same amount of boost too??

[ZeForce]

IEVAQ8, the 2 setups your comparing are quite different. Using and internally gated t28 turbo with a .86 rear housing, smaller exhaust and log manifold to a externally gated .82 rear housing 3037 with larger exhaust and tuned length manifold. naturally with a smaller rear housing, external gate setup and bigger exhaust and tuned manifold you would reduce lag considerably.


i originally had a GT28R on my 180sx. with the exact same setup and only changed the turbo to a 3071R with the same Comp housing and same .64AR t28 rear housing, the turbo was laggier (not by much) but yes it definately did make more power.

on both setup were you running the same amount of boost too??

I would also like to point out that the 0.82 T3 exhaust housing is actually bigger than the 0.86 T28 exhaust housing.

Anyways, I crunched some numbers... 180kw@wheels is roughly 300hp@flywheel which would require a flow rate of 28lb/min @ 12-13psi for a B16a. If you wanna check these numbers yourself check the garrett website for the equations. I have graphed the compressor efficiency for 4000-8000rpm. As you can see the 2871R and 3071R are pretty close to the surge limit and would definitely experience surge with a smaller exhaust housing. However, peak power does fall in a much more efficient part of the map and hence will produce more power but IMO this isnt really ideal for a street setup but much better suited to a dyno queen.

http://c1.ac-images.myspacecdn.com/images02/21/l_6bbf10bf98ee4d3f941ba98f6d42bd20.jpg
http://c3.ac-images.myspacecdn.com/images02/5/l_6e30c99ca4b545f8a3056915ff594f46.jpg
http://c4.ac-images.myspacecdn.com/images02/36/l_95ad1d5f82284751b24ff421ddb0580b.jpg

[Lukezen27]

Can't wait to see the results...

I'm in close tot the same boat lol

Custom 440HP Ball Bearing APS SR40 front and a Garrett 71R rear .86 Turbo

.86 a/r Exhaust, Flanges Supplied
.60 a/r Inlett, 2" Discharge, 2 1/2" Inlett

[IEVAQ8]

do you mind me asking which t28 you had previously? Looks similar to my T28R setup,
The GT2876r is rated at 480hp same as the GT3071r
hopefully it will respond similarly to your GT3071

it was the stage 2 avo turbo kit which is rated at 400hp liek i said with 0.86rear.....


IEVAQ8, the 2 setups your comparing are quite different. Using and internally gated t28 turbo with a .86 rear housing, smaller exhaust and log manifold to a externally gated .82 rear housing 3037 with larger exhaust and tuned length manifold. naturally with a smaller rear housing, external gate setup and bigger exhaust and tuned manifold you would reduce lag considerably.


i originally had a GT28R on my 180sx. with the exact same setup and only changed the turbo to a 3071R with the same Comp housing and same .64AR t28 rear housing, the turbo was laggier (not by much) but yes it definately did make more power.

on both setup were you running the same amount of boost too??

on t28 it ws on 8psi on gt30 it is on 7.5psi.....


I would also like to point out that the 0.82 T3 exhaust housing is actually bigger than the 0.86 T28 exhaust housing.

Anyways, I crunched some numbers... 180kw@wheels is roughly 300hp@flywheel which would require a flow rate of 28lb/min @ 12psi for a B16a. If you wanna check these numbers yourself check the garrett website for the equations. I have graphed the compressor efficiency for 4000-8000rpm. As you can see the 2871R and 3071R are pretty close to the surge limit and would definitely experience surge with a smaller exhaust housing. However, peak power does fall in a much more efficient part of the map and hence will produce more power but IMO this isnt really ideal for a street setup but much better suited to a dyno queen.

all good, but dont be fooled by the garrett calculator, it doesnt allow for a VTEC engine..........which is completely different characteristics to any other engine.............u cant compare a 1.6 litre barin engine to a b16 for example as vtec plays a huge part in almost doubleing the amount of air our exhasut blow out once in VTEC.............

their is alot of research to be done before turbo charging a honda.....
can i also point out..............the t28 graph i posted was making 178kw or so, but that was detonating as well, as the exhaust housing was way too ristrictive................

[Lukezen27]

their is alot of research to be done before turbo charging a honda.....
can i also point out..............the t28 graph i posted was making 178kw or so, but that was detonating as well, as the exhaust housing was way too ristrictive................

I remember when you were having those problems..

So it ended up being tht rear

[IEVAQ8]

I remember when you were having those problems..

So it ended up being tht rear

sure was the rear housing.............before i sold off my avo kit, i borrowed a friends turbo to do some background research......

we used a t28 with custome 1.06rear housing and didnt have a problem, but it didnt feel or was no where near as strong as the gt30 in the top end........

GT30 FTW

[Limbo]

yeah basically outflowed the t28r, but you have a b18 so there is abit of difference

[IEVAQ8]

yeah basically outflowed the t28r, but you have a b18 so there is abit of difference

b18 or b16, its the same principal..................high comp vtec............ask any real proper honda tuner

[ZeForce]

all good, but dont be fooled by the garrett calculator, it doesnt allow for a VTEC engine..........which is completely different characteristics to any other engine.............u cant compare a 1.6 litre barin engine to a b16 for example as vtec plays a huge part in almost doubleing the amount of air our exhasut blow out once in VTEC.............

wow Im a VTEC fanboy as well, but you give it way too much credit... VTEC doesnt make that much of a difference it's just switching to a larger cam profile after all. Our honda engines do have a greater thermal and volumetric efficiency compared to most other engines and that was all taken into account with I did the calculations.

[IEVAQ8]

wow Im a VTEC fanboy as well, but you give it way too much credit... VTEC doesnt make that much of a difference it's just switching to a larger cam profile after all. Our honda engines do have a greater thermal efficiency compared to most other engines and that was all taken into account with I did the calculations.

i will give our engines credit as they were designed back in the 80's and still one of the best designed engines..............i dont think untill the later 90's any other company was able to come close to it.............who would have thought of 2 cam profiles on the one cam?????

dont talk our engines down, u know u love them.....lol

if u took into account the vtec thermal efficiency and agressive cam profile in the vtec range then thats a good thing.......i still think gt30 is the way to go.

[ZeForce]

i will give our engines credit as they were designed back in the 80's and still one of the best designed engines..............i dont think untill the later 90's any other company was able to come close to it.............who would have thought of 2 cam profiles on the one cam?????

dont talk our engines down, u know u love them.....lol

if u took into account the vtec thermal efficiency and agressive cam profile in the vtec range then thats a good thing.......i still think gt30 is the way to go.

I do in fact love our greatly engineered engines, they are a work of art in my mind. However, I was just pointing out that our engines dont defy the laws of physics simply coz they have VTEC.

And Im not saying the GT30R is a bad choice of turbo but IMO it's designed for much higher boost levels and flow rates. It actually a very good turbo if you are chasing power over 300kw@wheels and a slightly smaller turbo might be better for someone who is chasing less power for the street.

[IEVAQ8]

^^^true true...........but for the money u cant go wrong............i'm only on 7.5psi and making a healthy and safe 239kw at the wheels (on a hub dyno) and if i want more i can............its also alot easier to make the power with a biger turbo even if the owner only wants 180kw........

it does make a huge difference once u take into account the vtec loads..............

im not the only one who has had probs with t28 on a vtec engine, and they were 2 different tuners too......

anyways, both our points are valid and have their advantages and disadvantages......

i hope our conversation can help someone...........

[Benson]

^^^true true...........but for the money u cant go wrong............i'm only on 7.5psi and making a healthy and safe 239kw at the wheels (on a hub dyno) and if i want more i can............its also alot easier to make the power with a biger turbo even if the owner only wants 180kw........

it does make a huge difference once u take into account the vtec loads..............

im not the only one who has had probs with t28 on a vtec engine, and they were 2 different tuners too......

anyways, both our points are valid and have their advantages and disadvantages......

i hope our conversation can help someone...........

Agree'ed honda loves their big turbo :thumbsup:

[Limbo]

b16 being a smaller engine does not boost as quick as the b18.
For the smaller b16, a t28r is fine for street, quicker than alot of stock turbo cars.
But i'm only after a small increase. The T3 is too big for general street driving on a b16, my friend has this and boost does not kick in till 5,500rpm, i've seen most of the b18s though come on alot quick at 4k.

If i can get boost earlier i'd rather sacrifice some top end for the drivability

[Limbo]

ok ened up getting the .86 rear, we'll see how i go

[Limbo]

Zeforce Can you by chance cruch some graphs again for me?
JUst wondering where the efficency is for a GT2876R with a .86 rear is? Thanks all that cruching is beyond me

[VTi_b0i]

b16 being a smaller engine does not boost as quick as the b18.
For the smaller b16, a t28r is fine for street, quicker than alot of stock turbo cars.
But i'm only after a small increase. The T3 is too big for general street driving on a b16, my friend has this and boost does not kick in till 5,500rpm, i've seen most of the b18s though come on alot quick at 4k.

If i can get boost earlier i'd rather sacrifice some top end for the drivability

exactly why i opted for the GT28RS for my b18....
but id love to know wat a GT30 or something would go like :p

[Lukezen27]

exactly why i opted for the GT28RS for my b18....
but id love to know wat a GT30 or something would go like :p

We'll see Christian..

Adrian (TODD among a few others think the 0.86 rear with be a good match.

The complaints about lag on these bigger rears is from other motors with low comp

[Limbo]

lol luke your on drugs you should read wat you post at times.

VTi boi - well based on what i've seen the RS,71 & 76 all have the same rear wheel.
My understanding is they should all react very similar on spool. The different front will allow for more boost..... due to bigger wheel....

Again i'll have to test this in real life. I've seen a R(mine) & RS in action, when i finish i will see a 71(luke's) & a 76(mine) in action.

P.S i'vee seen a GT3/4 in my friend's EM1, does 11s, but boost kicks in like 5k rpm and its abit of a dog to drive around the streets

Then we can compare abit more

[ZeForce]

Zeforce Can you by chance cruch some graphs again for me?
JUst wondering where the efficency is for a GT2876R with a .86 rear is? Thanks all that cruching is beyond me

http://c1.ac-images.myspacecdn.com/images02/14/l_1e2344f7c385485a82ba0b00312a2b3c.jpg

NOTE: This is just for compressor efficiency... nothing to do with exhaust housing size

[Limbo]

sorry i dun understand, can you tell me roughly what rpm that might be?
Is that basically between 4krpm and 8krpm again?

[ZeForce]

sorry i dun understand, can you tell me roughly what rpm that might be?
Is that basically between 4krpm and 8krpm again?

Yeah those points are 4000-8000rpm and 12-13psi required to produce around 180kw@wheels

[Limbo]

cool looks like the 60/71/76 & 3071 have very similar efficiency
Now all its gonna get interesting depending on our setups

[ZeForce]

cool looks like the 60/71/76 & 3071 have very similar efficiency
Now all its gonna get interesting depending on our setups

Yeah, at the end of the day it's all about the right combination of parts, manifold, compressor size, exhaust housing size, exhaust, etc all working together. The 2871, 2876 and 3071 have similar efficiency maps and all rated between 450-500hp but the disco potato (GT2860RS) is smaller and would offer more midrange power compared to the others and is still good for over 350hp@flywheel

[Limbo]

just to correct disco potato is gt2860rs

But thanks for your calculations, i'm abit dumb when i comes to complex calcs

[ZeForce]

just to correct disco potato is gt2860rs

But thanks for your calculations, i'm abit dumb when i comes to complex calcs

No problem I have been messing around with these calculations for my own turbo build. Just a reminder these are simply approximations to give you a rough idea for picking an appropriate compressor size. And I would like to point out for those that dont know, with a well designed manifold, correct exhaust housing size and efficient intercooler setup you may be able to make more power from less boost. For example, you might only need 9-10psi to produce 180kw@wheels with a B16a.


PS: Thanks for pointing out my typo :)

[Limbo]

i hear you on that. I know my b16 with the t28r made boost alot quicker than others. I think it was due to the intercooler setup by performance exhaust.
I'm hoping the new manifold will only add to the setup and with the larger turbo still be less laggy:cool:

then again won't know until we try it


No problem I have been messing around with these calculations for my own turbo build. Just a reminder these are simply approximations to give you a rough idea for picking an appropriate compressor size. And I would like to point out for those that dont know, with a well designed manifold, correct exhaust housing size and efficient intercooler setup you may be able to make more power from less boost. For example, you might only need 9-10psi to produce 180kw@wheels with a B16a.


PS: Thanks for pointing out my typo :)