By the way, you should be getting max power around 7k. You either need more advance up top, or you heating up things pretty quickly. Check your mat retard will dinoying and either remove some or rune wastegate until 5,5k to keep Iat down up top.

 

20* timing at the top 15* in the middle. Yea it could be at it's limit but I like to have fun with it. Putting a 2867 is the easy button so I wanna see what more I can get out of it first. Should be interesting. Do you have a Dyno or anything from your setup? Sounds like you are pushing this turbo as well

 

It's got enough advance my car has always been like this it makes peak at 6300-6500. Every engine and setup are different so peak might not always be achieved at the same rpm. There is no air temp correction until 50c I was only seeing 35c at most.

IAT isn't an issue I have a large Garrett intercooler.

 

To me my car is unusually torquey compared to other Miatas that are boosted. When I was running the 2560 I made 308ftlb and 296whp. I run a JDM 4w head and a flat top manifold. I have heard that the 5a intake cam timing is 2* advanced but I can't confirm that. Could maybe account for my high tq numbers. Also I am kicking around the idea of getting cam gears to see if there is anything there. Most everyone says waste of time. But I like to play with things

 

Not so easy button when Garrett is shuted down

Its not my car, just a car I tuned. You’ve got that advance pretty cracked up.

i was not implying you have a problem, making max power sooner, just pointing that shifting that power up the rev range may be the key for getting that 400hp.

 

For reference, I have a bp4w on squaretop and an exhintake, I make max power around 7100. That’s on a 6258 ( very similar compressor map @ this level).

 

I do agree I want to flatten the tq out a little. For one I just spin 3rd so if I can ramp boost that will be better just from a driving perspective. I'm still not at MBT I'm gonna need more octane for that.

Garrett will be ok someone will buy them. There are enough 2867s floating about, but Garrett better not go anywhere!!! Lol

From what I've learned tuning my own car it really wants the timing up top and it wants more but I can't give it to her. Probably need e85 for that lol.

 

Any VD runs or dyno of it? Yea that turbo is very similar in characteristics maybe a touch better at transient response. I have the bp5a cam I think it's 251*.

 

thanks for posting this up. I have a very similair set up and currently upgrading from a sr20 turbo to a gtx2867r gen 2. My goal isn't 373 like you've acheived but 325.

 

Good luck on your build man.

Added a video link to our YT channel. My buddy edited it. Please let me know if you like the video, if you do like and sunscribe!

 

Hey Andy,
quick question: What WG-Spring is in your GTX? I read, that GTX's are fitted with a 14psi spring, not a 7 or 8 psi spring, is that correct?

 

Yes that is correct it came with a 1 bar spring already fitted.

 

You should be able to specify which WG-Spring you want with your vendor. At least the few times I have ordered new turbo's that has been an option.

 

Yep that too. I got mine lightly used and it had the 1 bar on it which is fine bc I don't ever want to run less than that lol.

 

I have a Gen2 GTX2860R on the way to me in a T3 housing. I also have a local friend with a Gen1 GTX2863 on his miata. I am looking forward to testing them against an EFR. Also comparing to what andyfloyd hit.

 

Ohhhhh I cant wait to see that!!!! I love comparisons lol

 

The last gtx2860r I did was a total powerhouse, made 340 at 15psi on e85, but it was a 10:1 motor

https://www.instagram.com/p/CEs6aEdHgOL/?utm_source=ig_web_button_share_sheet

View this post on Instagram

I'd say it's pretty close to the efr if not similar.

 

Oh yea that's spicy. These are really good turbos on a BP engine. Mine does the same thing just annihilates 2nd and 3rd gear. Very nice

 

Awesome to hear. Especially since they drop right into all the rest of my hardware. Having a good quality upgrade path will be nice.

 

I have a built head that is pretty much ready at the machine shop, part of me wants to get a 2867R and make over 400whp easily. I probably wont, and ill stick with the 2860 and max it out but you know how it is with boost. You always want more.