Nitrous Oxide systems for our Boxsters
 

Given the advances in NOS with gradual,measurable power and improved reliability over the years, I wonder if anyone has had any successful experience with this power addition. Maybe Jack Raby and other engine builders can weigh in.

I'm not poo-pooing the idea, but there are limitations regarding applications. I believe every autocross sanctioning organization prohibits nitrous. For DEs or track days you might sneak by tech, but a full bottle might only give you a half-dozen or so Cinderella shots down the straight before your carriage turned back into a pumpkin. Might be able to surprise a few folks at the drag strip. It would be stunning to see a 10 second 986 kicking some mustang/challenger/camaro butt.

How much HP from Nitro could the engine handle?

spray and pray!! If I can still find my old dry kit from my old car, maybe i'll give it a try summer.

Only Mustangs I can't take (not modded) are the new Coyote motor cars, can't take SS Camaros either. Tried to get a Challenger to play, but he wouldn't go for it. The Boxster isn't a slouch, but a nice little burst would be cool to have.

Yup. I've had my fair share of straightline toys(ls1 fbody, lt1 fbody, notchback fox body, a couple Hondas even, and stretched/nitrous motorcycle), but the Boxster is by far the most fun toy I've ever had. Even though I don't consider it by any means fast. .......Maybe a turbo LSx powered 986 will change my mind oneday. ;)

I thought NOS was a fad and had not really heard of it since 2006 or so.

Then I met a kid at the high school. V6 2009 accord, fastest car at the school thanks to NOS. He always wants to race, I wish I could say that I say no for safety reasons, rather, I say no because I'm pretty sure Id lose to a Honda.

You'd just be losing to the NOS bottle, not the car it's attached to...
Like comparing apples to oranges.
Back a few years ago, a kid in an insanely modded '95 Civic wanted to run me in my bone stock '88 Mustang GT.
Whatever.
Of course he would have wiped me up with a full B18C1 driveline swap from an Integra GSR.
And he would have beaten up on an all-original low mile 22 year old Mustang.
Good for him.
I told the punk I'd get back to him after I did a total driveline upgrade on my ride, and then we'd run.
For some reason he wasn't interested then.

The factory pistons are way too weak for Nitrous in these engines. Once upon a time I designed an engine combination that would be optimized with Nitrous, but never had any interest in it from owners.

Done right, nitrous can be very impressive, done wrong its guaranteed to be explosive.

Address all the engine weaknesses before adding spray, or you'll learn the hard way.

Thanks Jake! http://forums.evga.com/upfiles/smiley/thumbup1.gif

About the only good use for nitrous in my opinion is drag racing. I don't see any Porsche as being a great drag car, and especially not with an M96. I consider Porsches to be more road racing/endurance type cars where balanced performance is key, not a few seconds of all out performance. Putting NO2 on one just sounds like a great way to blow head gaskets, break pistons or crack sleeves, and these cars already do a good job of that without spray. ANY failure on an M96 is expensive and almost always catastrophic.

I would put my money into correcting some of the inherent issues before turning up the wick.

So can we retrofit our M96 engines with cheap Japanese production car parts?

Dunno about you guys in USA and CA but here most of the street ricers owning Japanese cars uses NOS systems. Not all but a lot of them anyway (NOS are cheap kit here now). I can see their bright bleu anodized NOS bottle standing right there next to their hand brake level, center console, showing off and all. Never heard about a Jap car breaking down alone because of NOS boost

Are our German made cars really 'that' cheaper that Jap prod cars? Different compression ratio is what cause the issues maybe, higher rev? what is it?

Not too sure about Boxsters, but I was spraying a 75 dry shot on my Integra(with a stock bottom end) for 2 -3 years with never any problem.

......would have never guessed that you were into poetry!

I had a poet in my last M96 Engine Rebuild School.. Sharp guy!

Yes, the Asian cars have much better internals than the M96 in general terms.

Did someone say Poetry!?

When I blink, dim, then mine eyes don’t see,
A flash, was it my thoughts or eyes that looked on thee?

‘Twas a Boxster for all things highly respected,
Darkly bright, wildly fast, city streets directed;

To the clear day this Boxster shines a different light,
Thou building shadows do not make this Porsche less bright;

How would I say, mine eyes be blessed made,
Glossy black nine-eight-six racing through shadow’s shade;

How could thy shadows form such a beautiful show?
When to sunglass eyes thy shade shines stunningly so!

Behold, tis thee Boxster in the living day,
Through shade thy bright shine doth stay!

A blink, a moment, a Boxster mine eyes no longer see,
Ah, but closed eyes will always see bright when this Porsche memory shows thee to me.

And I thought the Boxster S's came stock with forged pistons... no?

Not all of them, and even if they were, they are still junk in regard to spraying them.

https://fbcdn-sphotos-b-a.akamaihd.n...9a79d2d5e797f2

My word...they are all coming out of the wood work!

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There was a guy in the UK that added a nitrous system before he sold his car. I asked him about it out of curiosity, and he said it was a wizards of nos system. Don't know how the internals would fare after many sprays. I am pretty sure he was very conservative.

Honda vtec motors are pretty spray and boost friendly. Low compression and stout internals. The 986 is a grenade with the pin pulled. Very different animals.

Yeah, I'm bumping an old thread.


This is the conundrum I always see with "boxster talk." There are always large numbers of people attesting that the 986 boxster-s is intentionally detuned to a degree, yet when someone inquires about gains through bolt-ons and dyno tuning... they are quickly shut down.

And once again, with nitrous, I've been thinking about it lately, though really am quite content at just having 99.9% of my fun flinging the car through corners.

With that said, would a conservative and progressive shot really be that bad? Forced induction is really out of the question and even if you can do it -- it costs a lot of money.

Nitrous can be controlled to come on like light boost and gradually add more power through the entire RPM range. (throttle and window switches along with a progressive controller)

I have no plans on doing it at this point, but would is this engine (3.2) really incapable of reliably holding a shot that progresses up to somewhere in the 50-75hp range?

that could add another dimension of fun to the car when you just have that urge to rip through a couple gears, and you wouldn't be just dumping a giant load onto the engine all at once... If the engine can handle a SC kit that adds anywhere in that range, there's no reason a progressive shot should be any more stressful. Plus we're not talking about using a **************** ton of giggle gas here, so you could use a fairly discreet system and not be filling it up all the time.. I don't care about drag racing -- I just sometimes miss having a bit more power.

Has anyone actually done it?
How much has this engine handled reliably with any other form of forced induction?

11:1 is low? I've put ~450whp through those engines on stock internals and have absolutely flogged the crap out of them for endless miles. I understand it's a different engine altogether, but low compression just isn't true for most turbo hondas.

Sounds like you've read the opinions. I wouldn't expect those to change - you're likely to get more of the same here.

And no, most people have not tried this because they don't want to take the risk of sacrificing an engine for an occasional 50-75 hp.

Someone would have to step up and give it try. Until then, we're all guessing...

Is there a ring land issue with the 3.2? With the successful turbo builds I've seen here and there on this forum I see no reason a progressive shot would be very detrimental. It's easier in the engine than a blower... you don't need the crankshaft to spin a bottle, but you need it to spin a blower

My other real questions here

The fuel system, is there enough injector and pump to hit it dry, or would a wet kit or injectors/pump/tuning necessary? If the fuel system has some wiggle room I wouldn't be too scared of a dry hit, if it doesn't , I absolutely wouldn't even consider risking it.


Hoping someone who has dealt with forced induction and stock fuel systems can chime in on the logistics with this subject.

I love the car the way it is, don't get me wrong. I still want a c5 or c6 project car to have forced induction fun with someday, but I bought the boxster because the power was not nearly enough to make the vette even hold a candle to the boxster imo. It puts a smile on my face every day and has made me a better driver in the process. I spent most of my life saying "meh" to Porsche in general, but now wonder what I could possibly rather have than another Porsche as a daily.


I've had plenty of way faster cars. I wouldn't mind giving this one a VERY mild kick once in a while. Engine weakness points and fuel systems are where I am having trouble finding reasons why it wouldn't work reliably, especially with the successful forced induction cars that have popped up. I haven't seen a thread where someone boosted a boxster and blew it up.

If you can find out the "smallest" wall thickness of the cylinders and its material composition, I can quickly run a sim and let you know what sort of psi you'll be able to run 'safely' within, both during detonation and compression for that 986.

Those 986 pistons and conn rods also (material), especially at the pin. Whether it is a conventional alloy, cast or not. That pin pivot point is where the force will be greater so the material of the pin is equally important. Shall it fail, the piston pivot point will let go before the pivot on the crank.

I bet the rings are heat treated 8620 conventional alloy already so this should already be good enough (just guessing here).

Start with that mate, obviously there are other pressure points that needs consideration but if the above sim fails there is no point carrying further analysis.

edit: Interestingly enough and confirmed; I've just found out that my boxster is all made of cheap cast (pistons, rods, all of it, literally). Could be wrong also of course (source: the Internet!). Frustrating... could have been fun to look into. There are tons of nos kit avail here and quite popular with the Japanese cars. In fact I don't know of anyone owning a Japanese car (at the track anyway) who doesn't have nos. They all seem to be running just fine