Only want to boost 6 psi
 

I'm only looking to boost 6 psi with a t25 on a ss autochrome turbo manifold and ebay intercooler and piping. Trying to go low budget.

I did a search and I don't see the AFM anywhere on the set-ups. What do I need to get rid of it or should I keep it around since i'm only boosting 6?


Thanks

Going 6 psi and on a budget means standalone ECU is probably out of the picture or unnecessary. That means you have to keep the AFM. Not too big of a deal at 6 psi.

Getting rid of it requires a standalone. Cheapest standalone is MegaSquirt at ~$350 for a DIY unit, ~$550 for a plug in unit. They go up, way up from there. There are guys who are running 16psi on the AFM and some hacks, probably start there. Is there a HP goal you're looking at? Why 6psi? It doesn't really say how much power you want/how fast you want to be.

keep it unless you're using some engine management, for 6psi (my opinion) all you would need is to replace the actuator that came with your turbo unless you know for a fact that it opens fully at 6psi (wastegate).

what piping did you get? I'm also looking for ebay kits... my goal was to
go at 6psi too but with all the stuff i bought already i may just start at 8-10psi...

whoa, those were some quick responses, lol...

Damn, those were quick responses!!

No real hp goals. Just whatever I can get with a turbo at low boost. It has an internal wastegate set at 7psi. Will I see much of a difference with a megasquirt? If I stay with 6psi, am I good to go with everything stock (no fuel and air management)?

I have a 99 head and intake manifold and planning on getting it ported and polished. Is $1000 a decent price for port and polishing? My car's a 94.

I didn't get the piping yet. But I saw a thread on here or somewhere about who to get the piping from on ebay and who not to get it from. I'll post the link here if i can find it again.


Thanks.

yeah responses were pretty quick huh, i thought i would be the first one, by the time i finished there were two already, lol...

anyway i don't wanna change your mind or anything but for less than $1,000 my car will run a good 200hp, or so i'm hoping...but port and polish, that would pull your wideband a bit higher, are you planning on boosting more later?

I'd like to say 'no i won't be boosting more later'. But I also bought this miata for $500 and said i'm not gonna mess with it. Suppose to be my commuter.

With the intercooler will I be able to keep my AC?

I've read these are good ebay sellers for intercoolers :

CSX Racing/ Just Intercoolers

https://www.miataturbo.net/forums/sh...iy+intercooler

here the post i was talking about

yes you can keep the a/c.



take a minute (or five) and read through my FAQ.

Halcyon, your thread is hot tonight, lol...
braineack, i'm about to read your FAQ as soon
as i finish reading the intercooler write up, lol...
cheers

Halcyon, these motors are bred for boost. Forget PandP until you're in the 300rwhp range.
2.5" IC piping is plenty. Depending on your particular T25, you'll need an enlarging coupler at the compressor outlet as it's probably a 2" or 2.25". The compressor inlet is also proabably 2", and I recommend all your intake piping be the same diameter as the MAS and then use a reducing coupler to enter the compressor inlet. I think it's probably 3"

You're not going to be able to limit boost to 6psi w/a 7psi wastegate. You can't reduce your boost level to below the base rate of the wastegate actuator. It's always possible to produce more, but not usually less. In reality, that wastegate is probably going to try to give you even a bit more than 7psi.

If you've been following my boost overshoot issues, be ready for that problem. When I get back from the Fredericksburg meet today, I'll be doing the wastegate-port mod and posting the results.

braineack: I've read your FAQ many times. :) But I'm not planning boosting too much so I'm trying to avoid most of the things you mention like boost, fuel, and timing controller.

Since there's a 7psi wastegate on my garret t25 i guess I'll go with 7psi of boost. Am I asking for trouble at 7psi? Everything stock and ebay piping and intercooler. Or will I be better off with stripes kit?

Samnavy: I havent been keeping up with your boost overshoot. Never heard of it until now. I'll be doing a search and reading up on it tonight.


Thanks everybody.

at the least youll need an FMU.

Without a timing controller your timing must be retarded to a point that you don't ping. Doing so loses low-end power.

You aren't even close to asking for trouble at 7psi if everything is done correctly.

Stripe's seems to be done selling the kits, however will sell the piping kits and you can source the same intercooler on ebay.

is Stripe's a member in this forum, ebay seller???

Seems to me that 7psi could be done with an FMU and base timing set at 8* with an intercooler as long as it isnt too small or the ambient temperatures are not too high. Further, Water injection could be added on for further security on hot days. It would not be ideal, but it would work I think.

ehh im just talking out of my ass

Don't be like me and buy all cheap stuff shooting for 6psi only to buy most things again to chase 12 psi. Even at low boost you will have to deal with fuel and timing. Once you get something adjustable you can add more boost easy.

if i have Megasquirt, do i need a vortech fuel pressure regulator?
If not maybe this can Halcyon with his set up...

With megasquirt, you can control fuel and timing, but without bigger injectors, you will need the fuel regulator.

Oh one thing I forgot about is your fuel pump. If you are using the stocker, I dont think it holds up with higher fuel pressures, but is able to flow well enough for what you are shooting for at the stock fuel pressure. Since you are new, i just want to make sure you understand that with boost, you need more fuel obviously and the two ways to do it is with raised fuel pressure or with bigger injectors which can flow more fuel at the same pressure. Theres more to it than that, but thats basically it.

I'll probably upgrade the fuel pump. Are the stock 94 1.8 injectors good enough? I think I've read somewhere the 1.8 injectors are good for low boost. If the megasquirt will control timing and fuel and is easy to install and tune, I might go with that. I just don't want a bunch of stuff that'll need tuning and dyno time. (Boy, it's starting to add up.)

Don't think I'll be chasing 12psi. This is my commuter and I want to keep it somewhat reliable.

Also, I just remember I have a DSM t25 so the exhaust section has 3 bolts. I'm assuming I could go to any muffler shop and have them fabricate something for me. Is this the way to go?

Mouglie: I was told stripes is the guy with the banner on the top of this forum "Mx5projects.com"