redhat778

I have a 93 r1 with original engine and turbos with 90k miles. Everything still runs great and the car already has a racing beat cb exhuast. I'm about to put an M2 dp and probley an apex intake on it. Is it safe to run the stock ecu with these mods? I will still be running stock boost also.
If you do recommend an aftermarket ecu please put which one.

Mahjik

iTrader: (1)

As long as you keep it at stock boost levels, you will be fine.

ttpowerd

Exactly...keep it at or under 10psi and you will be fine

redhat778

I think by having these mods it will put stock boost up to like 10.5 or 11 psi. is it still ok to run it with these mods?

Mahjik

iTrader: (1)

Just search for the "Home Depot Boost Controller", and limit your boost (*IF* you need to) when you add on your intake and dp. I wouldn't risk anything past 11 PSI on the stock ECU, although others have done it.

Just check your boost pattern after the install. If you see anything over 10, do the cheapy boost controller mod.

ttpowerd

If you need help installing anything or whatever just give me a pm and I will send you my phone #.

Mahjik

iTrader: (1)

AH!

That's what I like to see. Someone actually offering help! Big props to you ttpowerd.

Silex

Yea, I got all them mods and luckily have my external wastegate to limit my boost . All Io can say is good luck saving up for an ecu !

trigeek37

I had DP, intake, IC, cb etc with stock ecu and had a perfect boost pattern. the same day I finished many of these mods though, I upgraded my ecu... I just wanted to see want my pattern would be with the stock ecu. so I guess it is doable, but I don't think it is a great idea.

DaveMc

You're playing with fire. All it takes is one or two knocks and before you even notice that you got a boost spike, your engine is toast. Spend the money and get an upgraded ECU - it's cheaper than a new engine.

Mahjik

iTrader: (1)

At stock boost levels the stock ECU is more than enough:

http://www.newwave.net/~flanham/wlan.../3modrule.html

And he did say he was going to keep it at stock levels.

PVerdieck

Correct. Unfortunately there is now way to limit the boost levels to stock without modifications.

Before my PFC, I was running Catback/Intake/Underdrive pulleys. With that I could see 12 lbs regularly (on an Autometer gauge). That was enough for me, as I was about to install a DP.

Redhat, do you have a boost gauge?

Mahjik

iTrader: (1)

Home depot boost controller. If you read the entire thread you would see where I mentioned limiting the boost if he sees over 10 PSI.

95R2-89TII Ground Zero

Exactly the truth....just keep it near normal boost.

dpasseto

Thanks for the link....I'm in the same boat as redhat. I don't want to blow up my car but I want it to breath better and run cooler. I didn't see the part about the Home depot boost controller though.

dpasseto

I checked out the link and that looks a little complicated. Anyone in the Maryland area done this before that wouldn't mind lending a hand like TTpowered ;-)

Mahjik

iTrader: (1)

That link was just information about the Air/Fuel ratios with various mods and ECU's.

If you are looking for the Home Depot boost mod, check this link:

http://www.rx7turboturbo.com/robrobi...controller.htm

Flybye

Even with the boost controller, you MIGHT spike during transition. You might have to also install a second controller on the prespooler. Every FD is different, and there is no way of knowing that you will or will not spike until you actually have the mods installed.

This site has a nice little diagram on where the valve goes. You can also see the prespool line there, too.
http://www.rotarypowered.com/howtoboostcontrol.html

DaveMc

I still think you are playing with fire. You are definitely pushing the limit of the stock ECU with these mods, so one mistake may cost you your motor. Do you feel lucky? I'm not the gambling type, so I upgraded my ECU before I ever got close to the limit and subsequently added a boost controller and J&S for additional safety.

You might want to check-out the information at: http://www.scuderiaciriani.com/rx7/computer.html. You can find many people saying "Joe has mods A, B, and C on the stock ECU and he's fine", but you also hear a lot of "I got a boost spike on this cold morning and my car's now runs like crap". You make the choice - do you feel lucky?

Montego

iTrader: (1)

Hey instead of buying an ECU make sure that you have yourself covered for an engine first. At 90K, a rebuilt might be in your near future. Just a thought...

BoOsTin FD

I also have dp, catback and apexi intake, And i'm running 12-10-12. I was runing that with stock air box, dp and catback. My air fuel gauge shows 3rd green at wot.

I just want to know if this is ok, I mean with intake or without it I was runing 12-10-12.

redhat778

Thanks for all the help guys. But since the engine has high miles i'm going to say screw it on spending the money on an ecu at this point. I might not even do intake (probley will in long run). I'd rather save the $1200 for a pfc and put it to a $2200 engine. No cost for labor b/c my dad is a mechanic and has alllllll the neccesary tools. (He's got a miata and a vette). He loves the 7 and has been driving every chance he gets.

SilverRX7

Here is a junior Q, but I had to ask... how do you control the boost levels w/o a controller? I assume you cannot and the stock ecu just raises the pressure related to how much intake air is coming in... I have a knightsports ecu chip that has unlimited revs and a richer fuel mixture... is this the type of chip you are talking about? So if, and I havent yet, I install a K&N air filter and cold air intake box, I should also put the chip in as well or else risk running lean?