BIG TURBO: What do you need?

[EdgeAutosport.com]

Originally Posted by martin_nj no mention of boost control? from most of the threads i'm reading people are using aftermarket boost controllers...

mbc ftw

[martin_nj]

yah MBC or EBC - both are better than stock is what i'm reading

[Ziggo]

I listed the EBC as an option in my build thread. At $105 for a plug in 3 port I don't know why you wouldn't upgrade, but you don't HAVE to have it.


Zigatapatalka

[ganque]

*noob question*: What's the goal on having a MBC when you can control boost with the AP?

[martin_nj]

once you go BT the stock solenoid can't keep up too well is what i've read.

also it only goes to 22psi or so accurately?

[frodaddyweez]

I believe its the MAP sensor that cant read above 22.73psi or whatever. But yeah, you definitely want to go aftermarket with either MBC or EBCS.

[fywdyl]

Noob question.

With a big turbo, is a full TBE recommended or would the stock CBE be sufficient flow?

[martin_nj]

i dont think anyone has done a before/after dyno but i'm curious just how much the stock will flow.... 400 wheel?

[Chimmike]

Realgib made 400whp with stock exhaust manifold and CBE, so flow thru stock exhaust is not a problm.

As for using stock ebcs........I'm doing that right now. While not optimal, it seems to be doing just fine.

[chadgermano]

where can i find the other parts that go along with changing the injector seals. i am adding a new fuel pump, injector seals and 3.25 maf to my set up in a couple months and i want to make sure that i have all the small parts covered. right now i am running a gt3076r with dp, cobb ap, intake, inlet, atp front mount. i would like to know some good advise on a manifold that i should get and also i would like to change my setup to external gate. how would i go about doing this? thanks for all the posts guys and i look forward to the advise.

[J-Liss]

the biggest thing you need....money...add it to the list plz.

[dterranova]

fuck my life. i wish i never read this thread. there goes all of my tax returns...

Originally Posted by J-Liss the biggest thing you need....money...add it to the list plz.

or a willingness to have NO money...

[frodaddyweez]

Originally Posted by dterranova fuck my life. i wish i never read this thread. there goes all of my tax returns... or a willingness to have NO money...

Doooo iiiiiittt

[Tabasco69]

Originally Posted by Ziggo Quit spreading this crap, the bolt-on ATP hotsides are the same .55 hotside as BNR\Stock. Yes .55 sucks for everything except spool, but if you want something bigger you are going to have to go with a steedspeed or custom manifold, and are going to have to have a custom downpipe made, or modify one of the bolt ons. Other than that, yes the 3071 is capable of more power, the 2871\BNR spools better which is preferred is up to the user. Once a bolt on TS T3 manifold is available, it will be 3071/3076 as the only logical choices as they will spool like the 2871 but have much more capability. Zigatapatalka

2871r-460hp
3071r-480hp
3076r-525hp
Unless you upgrade to the 3076r why bother.....it is not like there are a lot of 500whp ms3 floating around here either, a very small handfull of them.

I run a gt2871r .62 hotside, I 'am getting 340whp/350ftlbs @17psi and it has a ways to go before it is near being maxed out- for me it is a good comprimise, nice linear powerband, a lot less torque steer, not a dyno queen but for me it is all about the powerband, .72 trimm IDK if I would like that very much, I don't care about the topend if I have to sit there and wait for it to spool, not an expert on twinscrolls but I have been told by quite a few fellow mucks that ts is not advantageous until you move up into gt35 series and above...face it small mid frames have no problems with spooling and that is the big deal about ts, running a gt35 that spools quick like a gt28/30

[Frecine]

Just bought a gt2871r got a ATP dp, cai, Cobb ap what do I definatly need before I put in the turbo ?

[martin_nj]

balls of steel

Originally Posted by Tabasco69 2871r-460hp I 'am getting 340whp/350ftlbs @17psi

how did the math work out on this? if you're at 17psi now what psi would u need to see 460hp?

[Tabasco69]

Depends on supporting factors that effect it's effeciency, ie contrictive intake or exhaust impact the numbers, availible fuel supply, IAT's, MAF capacity or clamping
oh and btw when you help tc out with supporting improvements for example moving to a better flowing exhaust/dp I went from 340 to 358 exact same boost

Garrett does not specify but assume this is hp to the crank, factor 12-15% parasitic loss through the drivetrain, for 4wd as much as 25% loss, but we look at the power that meets the road.... to us that is what counts

.15 x 425chp = 361whp (close enough for estimate)
*base dyno non fi 138whp
*17lbs boosted = 358whp (358-138= 220/17 = 13) so 13whp per lb of boost
so many variable to factor though but say a gt2871r is good for 24psi, 24x13=312 whp in addition to what the motor would make without it.

this all is conjecture btw.

[martin_nj]

Originally Posted by Tabasco69 but say a gt2871r is good for 24psi,

agreed that it is all conjecture, and i follow the reasoning, seems sound. main flaw i see this one. 24psi? isn't that a bit high?

[Tabasco69]

LOL more conjecture, I don't think it is high, or the ragged edge but I don't inttend on finding this out, I 'am sure there are some people who have tested it to it's limits of failure.

Based on

[Ziggo]

I am getting ~ 400hp out of my 2871, with a bit more timing you might get as much as 425 but I am knock limited right now. That's at 22psi, which is about as much as the turbo has in it reliably. You could push it higher but I don't think you will gain much from it. It is right on the right side of the compressor map.

[Tabasco69]

Yeah I think to get into the maximum effiency of a gt2871r you need to be near or aleast 20psi, I agree about 22psi seems like the maximum you want to push it reliably, if that is not enough then it's time for a 30 series, myself I would go to a gtx3076r.

ever consider injecting 50/50 meth or alcohol? that would allow you to advance the timing and get you to 425....but then again it is one more part that can potentially fail, kind of what has me on the ropes about it....aquamist seems to be the best system for the money, but it is a lot of money, I looked at aem system, I have heard about their controler being very unreliable though.....snow or devils own?

[blkspeed307]

Any boost creep associated with the gt2871 ?

[Mid_Life_Crisis]

If you are still on the stock seals and don't want to chance screwing up something that isn't broken, would it still be reasonable to give them a better chance of surviving by replacing the holddown assemblies?

[Tabasco69]

internal wastegate, yeah I had some, depends a lot on the dp flange design, the flange needs to be recessed enough to allow the poppet to fully open, whoever designed my dp did not do this and the vlave could only open maybe 30%, not a big deal running low boost but your fucked once you start making a lot of boost.
I ended up tack welding the iwg acuator stem and going to a 38mm tial ewg with a 1.5 divorced dump vta

Actually I had a fuckton of creep that oversped the compressor, I can say without a doubt 30psi surge will fuck the compressor blades up

new chra installed


example of a bad flange design that limits the iwg poppet valve travel



if you stick with the iwg setup ATP makes a welldesigned dp flange


I was working with what I had....a t25 turbine, if you are going to buy a new tc get a t3 turbine housing and find or have a custom dp fabbed....and a steedspeed or custom tc manifold, cant you add a ewg flange to the collector of the stock ms3 mani?, optimum placement of the gate is off a collector of all four runners pre tc.

I did it like this intresting fact this manifold is a mazda factory part, it was developed as a prototype when they were developing the ms3, not avialible to the general public.

[blkspeed307]

Gotcha thanks for reply . Still trying 2 figure out what bt route 2 take Gtx 3071r or gt 2871r , not looking for big HP numbers for a dd, & want to keep my upgraded UR dp & tp & corksport tmic have autotech fp internals already.
Thanks

[skiptowncat]

Is it advisable to get a 3 bar MAP sensor?

[EdgeAutosport.com]

Originally Posted by skiptowncat Is it advisable to get a 3 bar MAP sensor?

If you want accurate readings above 22.xx psi yes. I dont have one and im making some pretty decent power, I just have a good boost gauge and an mbc.

[Chimmike]

If you use ebcs like grimmspeed, you can't target above what the stock MAP sensor will see, so you'll need a 3 bar. I recommend one anyways for accurate logging. Easy to hook up.

You'll probably need a 3" MAF by the time you need a 3 bar MAP sensor anyways.

[rfinkle2]

Originally Posted by blkspeed307 Gotcha thanks for reply . Still trying 2 figure out what bt route 2 take Gtx 3071r or gt 2871r , not looking for big HP numbers for a dd, & want to keep my upgraded UR dp & tp & corksport tmic have autotech fp internals already. Thanks

IMO, ATP should make a GTX2871.

[adlpb]

Originally Posted by rfinkle2 IMO, ATP should make a GTX2871.

Yes sir. I agree. The only thing that is stopping me from going BT (other than moniez) is the fact that it would kill my auto cross times with the lag. Even the GTX3071 has some lag, spooling in the mid-high 3K's. If they would come up with a GTX2871, I'd jump all over it.

I'm reaching 20psi at around 2900. Not that you would reach that in autocross, but the sudden delivery of power at unexpected (higher) rpm's during turns is not good...IMO

[rfinkle2]

Originally Posted by adlpb Yes sir. I agree. The only thing that is stopping me from going BT (other than moniez) is the fact that it would kill my auto cross times with the lag. Even the GTX3071 has some lag, spooling in the mid-high 3K's. If they would come up with a GTX2871, I'd jump all over it.

That and you could basically max the turbo, and still have fuel.

Until the bigger injectors and fueling solutions hit the market, I can't commit to a BT.

I'd like to continue to run some e85, but don't want to use meth as a crutch.

[Tabasco69]

Originally Posted by rfinkle2 IMO, ATP should make a GTX2871.

they make a gtx2860 and 63 problem is the regular gt2871r still out performs both of them by a good margin, I agree they should make a gtx2871r version...the compressor wheel is the ONLY difference between gt and the gtx.

this swag but a regular 71r can push close to 40lbs of air per minute, which puts you close to 400hp, say the new compressor wheel jack up the flow another 6-7lb/min and that is about a 60-70 hp gain while staying within the sweet spot of it's peformance map

[Ziggo]

You don't need a GTX2871 to max the injectors if you are mixing, and based on my results you need some octane boost once you start going north of 300hp.

Getting above 400hp on the 2871 is more than possible. I am right there with a 3/9 mix and there is a slight bit more headroom on the injectors so a 4/8mix and a couple more degrees of timing and you are right there. Repeating myself here, but that's a big reason why I stuck with the smaller BNRS3.

I reach my boost targets just before 3k rpm. It doesn't go all the way to 20psi cause I am limiting it to ~400wtq


Zigatapatalka

[Chimmike]

20psi at 2900rpm on anything but a stock turbo will not help your autocross at all. All that will do is assist in breaking traction sooner.

[martin_nj]

Originally Posted by chimmike 20psi at 2900rpm on anything but a stock turbo will not help your autocross at all. All that will do is assist in breaking traction sooner.

this is not true if you use the new Gorilla Glue tires that tire rack sells

[rfinkle2]

Originally Posted by Ziggo You don't need a GTX2871 to max the injectors if you are mixing, and based on my results you need some octane boost once you start going north of 300hp. Getting above 400hp on the 2871 is more than possible. I am right there with a 3/9 mix and there is a slight bit more headroom on the injectors so a 4/8mix and a couple more degrees of timing and you are right there. Repeating myself here, but that's a big reason why I stuck with the smaller BNRS3. I reach my boost targets just before 3k rpm. It doesn't go all the way to 20psi cause I am limiting it to ~400wtq Zigatapatalka

The BNR S3 looks better to me everyday.

I want to continue to run some e85, and there is no way I could run the concentration I am now with the stock fueling (@ least from what I can gather).

If I could have a consistent 400 wtq through most of the power band, I would be plenty happy.

[Chimmike]

Originally Posted by rfinkle2 The BNR S3 looks better to me everyday. I want to continue to run some e85, and there is no way I could run the concentration I am now with the stock fueling (@ least from what I can gather). If I could have a consistent 400 wtq through most of the power band, I would be plenty happy.

but why when you could get 400wtq with a gtx3071 on 93 without ever having to touch e85? And when you did, you could hit that on less boost.

I don't think I'd want to push an S3 there, IMO the benefits of the 2871 far outweigh the negatives for going that route vs. S3.

[rfinkle2]

Originally Posted by chimmike but why when you could get 400wtq with a gtx3071 on 93 without ever having to touch e85? And when you did, you could hit that on less boost. I don't think I'd want to push an S3 there, IMO the benefits of the 2871 far outweigh the negatives for going that route vs. S3.

I really don't want anything ewg, don't want the creep of the gtx3071 (never ported anything and don't think a brand new turbo is a good place to start), and tbh, @ least from what I can read, the ATP kits are half assed.

It is really hard to get a handle on what can / can't be done with all of these turbos, as far as power levels vs. fueling.

[Chimmike]

my gtx76 has no creep. I wasn't aware that Jackson was fighting creep on his gtx71. I didn't do any porting.

[rfinkle2]

I'm pretty sure he just posted he is creeping (x>26 psi) in ckmazdaspeed3's build thread.

EDIT: hyperlink to Jackson's post here:
ckmazdaspeeds big turbo build 1


I know cld12pk2go ported his before even installing.