My twin supercharged tbi 350 miata build

[1project2many]

I believe Bob used the 7749 and $58 from the Syclone / turbo Sunbird. It's workable code but some people have found it takes a bunch of time to get some of the transitions worked out such as switching from decel to accel. Even if the car wasn't that fast, it had a cool factor that's tough to match. I agree that a single, properly sized SC might be more fun and easier to tune.

Regardless, you're going to have a cool car when done.

You might also want to check out a turbocharged TBI Cavalier that used to be on v6z24.org. Username was 1redry. Car was built (IIRC) without an ecm that was boost specific. IIRC he made decent HP numbers for a mild car.

[Shawn1989]

I believe Bob used the 7749 and $58 from the Syclone / turbo Sunbird. It's workable code but some people have found it takes a bunch of time to get some of the transitions worked out such as switching from decel to accel. Even if the car wasn't that fast, it had a cool factor that's tough to match. I agree that a single, properly sized SC might be more fun and easier to tune.

Yeah, i have no clue about the computer stuff. I can wire it all up but when it comes to tuning, i'm at a loss, hence why Dave is in the picture.
I am running a 16196395 PCM that was previously tuned by eagle mark. Unfortunately, he can't guide me anymore. I don't see how a single supercharger will be any different than twins..... turbo's most definately, but superchargers are belt driven so a projected RPM will be the same every single time [single or twins] rather than a turbo which will fluctuate.

Regardless, you're going to have a cool car when done.

I sure hope so! :D

You might also want to check out a turbocharged TBI Cavalier that used to be on v6z24.org. Username was 1redry. Car was built (IIRC) without an ecm that was boost specific. IIRC he made decent HP numbers for a mild car.

I'll see if i can get ahold of him. Thanks for the info.
With you saying without an ecm which was boost specific, do you mean that he just has a timing box, and a 2:1 FPR controlling it?

[1project2many]

I don't see how a single supercharger will be any different than twins.....

Heat! More heat. And the noise, noise, noise, noise! Like my Grinch impersonation? :)

With you saying without an ecm which was boost specific, do you mean that he just has a timing box, and a 2:1 FPR controlling it?

I don't remember what he had for additional controls. But the ecm had stock programming so something had to be adjusted.

[Shawn1989]

Heat! More heat. And the noise, noise, noise, noise! Like my Grinch impersonation? :)

lol well i knew that, it's going to be intercooled with water/meth so i don't think heat will really matter that much.... As for the noise, the more, the marrier! Haha the more it screams, the more it intimidates :]
Yeah, first thing i thought of was the grinch lol.

But, i was talking about how the tuning would be different from twins vs single

I don't remember what he had for additional controls. But the ecm had stock programming so something had to be adjusted.

Ok well i just emailed him because he hasn't been on v6z24 since October of 2014, so; my fingers are crossed.

[Shawn1989]

his reply word for word:

wow
were talking apples to oranges here, but I will let you know what I've done and you can take it for what it is. I sold my cavalier about 2.5 years ago as I was unempoyeed and did not want to file bankruptcy, so luckely that pulled me through until I got a job, sad day that was..

In anyrate,

My ECM was not tuned, however I did have a custom tune from superchips. Since my TBI was an high impatence injector to start, I was already in good shape. I had a 10:1 FMU for fuel manaement. Only thing I had done was port and polished the heads, all stock bottom end. Through the research that I've done, I know that the block was good for about 350HP (no kidding). My goal was no more than 300 (which I've never reached) reached about 213 or so at the wheels. (still isn't bad consitering that the stock was 90HP from the factory. Poor 2.2.

In your case, not sure where to begin on that one since your dealing with a supercharger over turbo. In my opinion, turbo's are easier to deal with but each case is different. No wide band. I had mine tuned in from a local speed shop here in dayton, did an ok job. drove it about 3000 miles with no issues, check engine line or anything so I'd say it did ok for me. But mine was more for show. I've taken it to many of shows and won. But didn't want to be one of those guys who did all show and no go.

I hope this helps.

[Shawn1989]

http://home.windstream.net/mcfly/tuning_fuel.htm

i just read this whole thing.
he didn't tune his via the pcm, how reliable do you think this is and how good will the engine run?

[Shawn1989]

Progress.



I began painting the inside, but then the wires wanted to put up a fight going where they needed to go. So i ran the wires and now i'll go back in, sand down, tape, and spray around them to clean it all up



Running engine stuff through the trans tunnel rather than the firewall. It should help clean it up a little bit.


Painted the bay, came out good for being the good 'ol Rustoleum rattlecan.


Ran the fuel, brake, and clutch lines today since it was all dried up.



I should be able to get the inside of the tub completely redone tomorrow. I'll post pics; then it will be time to work on the engine again.

[Shawn1989]

Does a free tune come with it ;)

[dave w]

Does a free tune come with it ;)

Likely not.

Once you figure out what computer you want to use, the next decision is the bypass valve control.

"Bypass valve: I should also mention the Bypass valve. The bypass valve is a release which vents off pressure in a rapid de-acceleration situation. When the Supercharger is producing boost and you abruptly let off the gas, closing the throttle plates, the boost has nowhere to go - kind of hard on everything. The Bypass helps relieve this and also helps smooth out your idle. Under idle or normal driving (vacuum) the valve is open. When it sees a boost signal it closes. This is also helpful in building up boost quicker. I have tried a standard Bosch 1" and a Vortech Race Bypass Valve."


dave w

[Shawn1989]

I have a bosch one from a saab/audi for each blower. When it hits boost; it closes

[Shawn1989]

A local guy MIGHT be able to tune it...... however, before i do that i would like to run it on a rising rate FPR through a load to see if it going to throw this belt..... if not then ill take it to the dyno and see what he can do :] need to grab a 2 bar map sensor though.

anyway, fleabay came through lol

[dave w]

I wonder if the local tuner uses a similar AFR spreadsheet to tune with?

dave w

[89S10_Project]

The car is just SICK.

It also looks vaguely familiar. Are you by chance in Charleston, SC (please god, yes.... I'd love to see this thing!)

[badbrad]

this is hideous....I love it....I'd love to rent it one weekend!!!!