How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Hello all, I am not familiar with reading compressor maps and had a member help me pick a turbo for my hp goals. Anyway, I was wondering what the limit is of a GTX2867R on a B18C with the following mods that are relevant are as follows:

Head:
Stock GSR Cams and oem gears
Supertech Valvetrain
Ferrea Valves

Block:
Eagle H Beams
Mahle 10.5:1 Pistons

GTX2867R with a tubular log manifold

I am tuned at 369 whp @ 17 lbs of boost but we stopped because my 750cc injectors were as far as they were going to go safely. I was just curious of how much more hp I could get out of her if I upsized injectors. Any help is appreciated. Thanks!

re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

A little odd that your 750cc injectors topped out at 370WHP. Are they older RC style injectors, or Bosch EV-14 style? Are you using E85? What was your duty cycle at? That dyno may be reading generously, but 370WHP @ 17PSI with a 2867 is pretty good as it is.

Only way to ultimately tell how far that turbo will take you is to up the PSI and see what it reads on the same dyno. I wouldn't run the turbo on the edge of it's efficiency though, maybe 20-22PSI on your current setup and call it a day there with whatever the results are.

https://www.garrettmotion.com/wp-con...p-GTX2867R.jpg

re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

I would agree with this. You have to look at what the purpose of the use of the turbocharger is. 369whp at 17psi of boost pressure at just under 48lbs/min airflow isn't anything to laugh at with a 1.8litre efficient Honda engine. You need to check to see what your base fuel pressure is, as well as the type of fuel you're using as ChanceEG mentioned. Depending upon the fuel, the efficiency range is about up to 26psi or so. Just be careful that you're using too small a turbocharger for the wrong purpose. About 420-430whp is about as much as you can push out of that. But that's understanding the turbine map , not just the compressor map.

The turbine size and profile determine maximum power output based upon the exhaust energy of the engine. The compressor map just deals with airflow and behaviour of the turbocharger. It's only one side of the cube.

Purpose of what you're doing matters here. ;)

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Thanks for the quick and informative replies! I am tuned on 91 octane, my injectors are the older style RC, not the EV14. As far as duty cycle, I cant remember what it was at. I just wanted more power but I also don't want to over work the turbo either. So here is the story about why I want to get more power:

I originally built the car for autocross, track days, etc. I love the car for what it is and at those power levels. However, I went out this year and ran it at Pikes Peak Airstrip Attack just for fun. I wasn't all that impressed with the outcome. Top speed was 134 with no launch (couldn't launch due to rules and not wanting to tear up the runway). Anyway, I came back and wanted to go for bigger power. I was going to get a bigger turbo, injectors, and a different exhaust manifold. However, I fear that the limiting factor here is my stock sleeves plus I would also have to swap out my Skunk2 Pro intake manifold for a Victor X. More or less, I am now aiming for 5-600 whp but there are many more variables that I need to account for like axles, transmission, etc.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

What transmission are you running, and were you doing a long pull in 5th?

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

S80 transmission 100% stock. 3rd gear is starting to grind a bit so I need to rebuild it anyway. Just not sure what would be considered an "upgrade". Haven't done much research on what to get and what is better. I will get around to that though but open to suggestions.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

I'd say your fuel is another limiting factor, you probably on the edge of the knock limit of 91 Octane at the power and boost level you at. Sure some Evo's run similar power levels with more boost but then that engine is designed to use very little ignition timing and has a sub 9:1 compression ratio.

A change to 93 octane or some E85 added to the mix would be advisable to avoid any damage to the engine in my opinion. E85 and ~22 psi should net you a super fun and responsive 400whp with lots of safety margin

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

STC TR3030R, or Banshee T04B would both still be fairly responsive and net you high 400, maybe low 500 depending on the dyno and fuel/other mods.

Could try the G25 660 if you have big bucks and wanted to be a pioneer. Low to mid 500s.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

You can keep the intake manifold for that power level, but after about 500whp, you need to re-inforce the block anyway, due to increased cylinder pressures. The intake manifold is the last thing to sweat

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

If that tubular log is the double T version well its a spool happy combo with a gt28 turbine wheel but i bet your tuner had to lower ignition advance.
This is killer combo on water meth injection(classic non honda low VE european setup) but without it the added pressure pre engine and pre turbo will limit you.
If you want to continue with this turbo/fuel get a boost by injector PWM water meth kit. It will be a different animal. If you have any other ehxaust housing other than the 0.8 one on t28/band forget everything, have fun with the car and sell the turbo
kit as is when you are ready for bigger things.

If you have the 0.8X a/r turbine housing and want to try to keep the turbo start with this:

https://cimg3.ibsrv.net/gimg/honda-t...c8339c57aa.jpg

Thats a great deal on a GREAT manifold. The only reasn its still on sale is probably cause its T25... With this you have MUCH better results. I bet you wont loose more than 200-300 rpm but after 5550-6000 youll gain A LOT of power and reduce
the knock of that double T manifold a lot also. On that 4 and 5 gear high resistance pull your tuner will love it.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

That IS a great deal for that exhaust manifold, and it's the right type. (A/R has nothing to do with whether it is sized or not until you look at the exhaust wheel size and profile for the use given.). But that is definately MUCH better than what's currently being made out there now. (No disrespect to Go-Autoworks.. ) Balor_Gr knows what I'm referring to. :hugs:

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

What money you save on the manifold you would have bought instead you can use to buy the G25-660. :)

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

And with that you would need a new exhaust manifold anyway, as those are v-band only. for non-actuated units. The Actuated ones have an option of a .49A/R T25 or for the larger units a T4 turbine.

G25-660 Garrett turbine lineup

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

I talked about existing turbo a/r because the 0.8 one with the gt28 wheel will flow close to gt30 wheel at t3 .63. Around 20lbs/min if i remember correct. This way he might actualy be able use the added flow to extract whats needed to max the compressor wheel. With the .64 a/r/gt 28 combo he wont go anywere close to max that 400-420whp compressor wheel.
Yes its a perfect mabifold for him for this situation. He wont find a better t25/t28 manifold like ever used.
God dam it when theyll release the G-28 or G-30 versions of G series!

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Is that the case even for the G25-550? I saw the website, and the 'flange diagram' showed T25 as an option, but if that's only for the actuated ones, then never mind!

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Yes the G series wg turbos are either Vband or T4 divided. EFR 7163 is probably the best bet on internal wastegated T25/28.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

"better"...I've made and offered a manifold nearly identical to that for EFR setups. Manifold offerings are highly dictated by demand (paid order) and success history here.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Very true.. Very VERY true indeed. For what it takes to make that style manifold in those proportions is a lot of time and effort, and most here aren't ready for that type of cost for such low demand. LoveFab made those on a regular basis, but due to the cost and time to create, they were normally out of the budget of most people at the time for B-series Hondas, unless it came as a package deal or something similar.

As for the .8XA/R for the the GTX28R series. Theoretically it seemed to make sense. But after a few years of people using that combination with such large 1.75" (44.45mm) diameter primaries, that combination for a "street setup" wound up being an abomination that didn't increase top end power significantly, and actually slowed recovery spool exponentially. :(. It was a sad day for that trend about 6-7 years ago.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Yes i know exactly what youre talking about on big piping. Internal volume sucks. Also high volume manifold with small turbo is not that good unless youre doing multilap sessions.
On the other hand its allways better to have free flow piping for the first inches 5-6-7 inches especially on a high VE engine. After that you can reduce it and to match the turbine housing
acceleration opening. Or you can place the collector there go for thiner single pipe from there all the way to the turbo.

Re: How can I Understand the Limits of my GTX2867R on my B18C1 project?
 

Very few people have the means and wherewithal to have the choice to do anything that way in the United States. Not without extreme inconvenience and cost. If that were the case, there wouldn't be an FI section here at all. It would have been like it was back in 2001. ;)