MazdaMike

im just looking to br able to run 14-45lbs of boost with open exaust and intake (prolly an intercooler also) but mostly keep boost at stock levels with a profec b. i just want to be able to not run lean and up the boost when needed heh. which one will be better for the job i dont know i look at ur guys opinions as unbiased and value them much higher than when i call pettit/m2. just wondering what u all though
-Mike

Street King

For 45 psi go with the M2, Pettit only goes to 42.5.

Seriously, I think that the Pettit only let's you go to 14.2 psi with the unlimited chip, the M2 I have no idead but it is said to not run a mid-pipe with the M2 ecu. I have the M2 ecu, haven't got my car back from the shop to put it on.

MazdaMike

ah **** that was a mispring lol 45psi i would **** my pants before they spooled up heh im sorry obut the misprint. 14-15

Blade7

uhhh. why don't you just invest in a power fc or similar units? You can go as high as you want and low. plus its a better unit over all.

YayeR

I've always wondered the same thing..

Chaz

Well to me it sounds like he doesn't have any big plans for moddifying his car, espicially the fuel system. He wants to run a lightly modified car and only wants to be able to safely turn up the boost on those "specail occasions." So if this is all he's after I think he's better off saving his money and buying a chip rather than spending the money on the Power FC and then finding someone to tune it correctly for him. Seems like smart reasoning to me.

YayeR

ahh cheapness, good word and it makes sense.

Chaz

Why do so many people here think it's a bad thing to spend the amount of money on your car based on what your wants/needs are for your car rather just going out and buying whatever happends to be the most expensive or has more "toys" than you really need? Just because he doesn't plan to heavily modify his car and doesn't need to spend over a thousand dollars to upgrade his ECU you act like it's a bad thing. There is nothing wrong with the M2 or Pettit chips, they just don't allow you as much flexibility down the road if you have further plans to heavily modify the car or for going single turbo or something like that. Buy a used Pettit Unlimited and then if you change your mind down the road and decide that your modifications justify or necessitate a unit like the Power FC or Haltec, then you can sell the chip and probably break even on the cost. Considering his specific circumstances I'd like to hear your reasoning on speding more money for functions he's not going to need or use, at least with his current plans. Not to mention with a chip it's simply plug and play with no tuning experience required.

Chaz

I think it's a lot more helpful to everyone on the forum for giving some reasons for your answers rather than just replying "Buy a Power FC/Pettit Unlimited/M2/etc." Give the guy a couple of pros and cons of each so that he can make a reasonable decision on what unit would be best for him. One of the reasons for posting the question on the forum was to try to get an unbiased answer after all.

BTW, MazdaMike, I believe this topic was discussed fairly recently so you can find some additional help for your question if you do a search. Good luck with your decision!

Red-Rx7

I agree with Chaz on this one..

When looking into an ECU system to buy, I recomend asking yourself these questions:

1) How FAR do I want to go with my car?
2) Where is the nearest dyno shop?
3) How much money do I have to spend?
4) Is gizmo's important enough for the more complicated systems?

If someone is looking to do power mods for the "everything up to single turbo", then most look at either the PFC/AEM/Remapped unit.

I asked the following questions above and gave a recomendation. Each person is different.

I personally believe that if you are going to go with a full setup, and planning on not running more than 14-15psi of boost, then I say grab a Pettit Unlimited.

We have a car here locally that puts down 357 rwhp @ 15 psi of boost. He runs full exhaust, intercooler, intake, etc. He also uses the Pettit computer.

Also on the dyno, A/F #'s were displayed. Under max load (5100 - 5500) rpms, the highest A/F was 11.7:1. The average was about 11.3 : 1, and in some areas down into the 10.7-9:1 ratio.

This is reliable A/F power. All he needs to do is keep the engine tempatures down, use good clean gas, and a good spark plug... he is set.

On the flip side, he CANNOT tune for more horsepower.. but really.. is it worth it? To him its not. Is it for you?

shaun.sheldrake

Can you expand on the etc .. 350ish is my goal .. would like to know what he has done to achieve that ..

Mahjik

iTrader: (1)

He's done that.


Check this thead:

https://www.rx7club.com/forum/showth...threadid=98411

Look for RTS3GEN, and you see can a list of his mods. I know that list isn't up to date (he just ran 11.77 in the 1/4 mile today), but it's close.

shaun.sheldrake

Thanks .. looks like a good 18 month long shopping list for me!!

MazdaMike

thank u guys for sticking up for me. heh my goal is more like 300, im only 18 and to be honest its hard controling myself as is but i dont have the money or the responsibility to handle 350+ although 350 is soundin kinda nice now either way it is more of my street car than track.

thanks for the help im leanin towards the pettit unilimited now.

-Mike

Marshall

Mike,
I made 351 rwhp with the M2 at 14 psi. The ECUs are identical AF wise (petit unlim/ M2 III). M2 may be a tad more conservative with timing but I'm not sure. Either should suit you fine.

jpandes

Damn Majik, That's one sweet looking engine bay!

jpandes

Marshall,

Can you post your Mods? I'm running the M2 Stage III ECU as well. I want to make sure that I haven't missed anything on my way to 350 rwhp.

~ John

Mahjik

iTrader: (1)

Thanks, but it's not my car. I wish my engine bay looked like that.

His forum name is RTS3GEN. He ran 11.77 last weekend.

rynberg

If you live in California, I would get the M2 chip. The timing is programmed for our crappy 91 octane, while the Pettit is more likely tuned for 92 or 93.

I agree with some of the points Chaz made but there are advantages to going with a stand-alone such as the Power FC, such as:

*no more 3k hesitation

*car runs much smoother overall with a 16-bit computer running things

*you can control things such as when the fans turn on to help keep your temps lower

Marshall

John, only thing I have that you don't is a resonated midpipe, profec B, and greddy pullies.