Why not NOS? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

dmcutter · 08-08-2008, 01:24 PM

A buddy of mine just got a custom nitrous system for his 70ish Buick Skylark GS. He said "I bet you could get your Boxster sprayed for about $500" which piqued my curiosity. I searched this forum and found a thread from about 3 years ago where someone said Toolpants had sent him a pic of a Box with a nitrous tank in the trunk, but no technical details. Obviously, nitrous is not something you need in the twisties, and okay, it does seem a little juvenile on a car like the Box, but for cheap, straight line horsepower, why not? Is it doable, or is there something about the engine that makes it a nonstarter?

ekam · 08-08-2008, 02:07 PM

Quote:

Originally Posted by dmcutter

it does seem a little juvenile on a car like the Box

No it's plain dumb.

dmcutter · 08-08-2008, 04:06 PM

Hey, thanks. That's just the kind of insightful, technically competent and thorough explanation I was seeking.

RandallNeighbour · 08-08-2008, 04:13 PM

I don't think I'd do it to my boxster because it could blow the engine.

It could blow any engine in any car, but replacing the motor might cost $2k or less for a rebuilt one... whereas a rebuilt boxster engine is $7k plus installation, right?

It seems to come down to risk.

I do wish someone would do it though.... and it should be YOU.

Get busy and come back to this thread with pix and video of it in action. We have a need for speed! :dance:

Jeph · 08-08-2008, 04:27 PM

Quote:

Originally Posted by ekam

No it's plain dumb.

And that's why I fully support your decision to do it. Ha!

I too have always wondered about juicing a Boxster. Most people, I find, have little to no experience with Nitrous. That's why you hear cries of caution when approaching the idea. They don't know much about it or have had little experience with it. (People fear what they don't know -who said that, Batman?)

In my several years of participating on this forum, I have never come across an individual who has juiced their Boxster. You'd be a pioneer!

I think it's something I would do to mine. I'd go SMALL though, nothing more than a 50 shot. I don't think I'd trust a $500 job though. I'd track down a Nitrous expert and some one that knows Porsches. Ask the right people the right question.

Anyway, go for it and post your results. You shall be the 986forum guinea pig!

dmcutter · 08-08-2008, 05:36 PM

"I don't think I'd do it to my boxster because it could blow the engine."

But WHY could it blow the engine? What does that mean? The crux of my original post was, what are the technical limitations of the engine, what would the failure mechanism be?

Sorry Jeph, I haven't bought into this idea yet-I just said my curiosity was piqued. After all, Boxster drivers typically say that on the track they can carry equal or better speed through the corners compared to 911s, but they lose time in the straightaways, which is where the juice could be used.

Boxtaboy · 08-08-2008, 05:52 PM

Quote:

Originally Posted by dmcutter

"I don't think I'd do it to my boxster because it could blow the engine."

But WHY could it blow the engine? What does that mean? The crux of my original post was, what are the technical limitations of the engine, what would the failure mechanism be?

Sorry Jeph, I haven't bought into this idea yet-I just said my curiosity was piqued. After all, Boxster drivers typically say that on the track they can carry equal or better speed through the corners compared to 911s, but they lose time in the straightaways, which is where the juice could be used.

But would it be practical to use NOS on a track when you're doing multiple laps? I thought NOS was more for single sprint runs for 1/4 mile races and such.

Jaxonalden · 08-08-2008, 07:08 PM

In the early days of being "on the bottle", novice individuals gave the concept a black eye by not properly metering the squirt. To much gas tends to get a little to hot and things that are suppose to move will become welded together.

Current systems are pretty much full proof. They come with jets that meter the correct amount of fuel and fog and solenoids that will shut down if pressures aren't enough. I wouldn't worry much about blowing the motor, then again I wouldn't go putting in a 300 shot and expect my bottom end to hold together unless I strengthen it. Any car should be safe up to a 150 squeeze.

RandallNeighbour · 08-08-2008, 07:22 PM

Mr. Cutter, that settles it. You have no excuses.

We want to see a juiced boxster ASAP and it should be your car!

(See how easily I appointed you instead of me?)

fragdude · 08-08-2008, 10:12 PM

Spraying a car that is used reguarly just does not sound like a good idea. I have heard some horror stories about using nitrous (one involves the crank coming out of the block).

What I do know about nitrous is that it adds oxygen to the fuel/air (for those that know chem N02) mixture which creates a more intense explosion plus the release of the bonds from the no2 mixture. This in turn creates power (which we all love). But it effects the parts of the engine. I assume its like putting a turbo in that adds the same amount of power. The seals get worn, the bottom end gets tested and the engine gets worn out because when it comes down to it the engine isn't meant to take much more power than what it puts out.

I think asking, "what happens to the engine when you spray it," is like asking the same question for turbos/super chargers. The engine isn't meant to put out 50% more power than it does normally. If it was, it would probably put it out stock.

As much as I would love to see someone spray their car, I would cringe just as much. If you want more power just get a turbo. Its more expensive, but I would argue that its not as bad and you don't have to refill a tank. Or if you have the $$ just get a bigger motor.

I personally have no need for more power. I raced an m3 today on the highway and I kept up with him from 65 to 130 (neck and neck). Granted he would dust me from a stand still, but I could have bought an m3 instead if I cared that much about traffic light racing....

Tool Pants · 08-08-2008, 11:04 PM

What picture....

insite · 08-09-2008, 04:49 AM

if it's done properly, it's pretty safe. probably more so than turbo or supercharge boost since the charge is cooled & has a cooling effect on the motor. it's important that it's done right for two reasons: first, not enough fuel = lean mix = detonation = bad. you have to add larger or extra injectors. usually an extra injector is wired in just aft of the throttle that just dumps fuel when the bottle's on.

the other thing to be wary of are the cylinder pressures. we already run 11:1 compression. this is why if we turbo/supercharge our cars, we can only ad a LITTLE boost. if the cylinder pressures get too high, things start to break. a properly engineered system would be fine in any car.

j.fro · 08-09-2008, 04:56 AM

NOS on the Boxster would be a lot more than $500. For around $500, most of the kits are plate or fogger systems to be used with wet intake manifolds (ie, carburetors). This is what you see on Chevys and Fords. It's a plate sandwiched between the carb and the intake. It's plumbed with the nitrous and fuel, which usually has it's own dedicated fuel pump. During combustion, things get hot enough to release the extra O2 molecules from the nitrous. The extra fuel helps to slow the burn and cool things down. Without the extra fuel, things get lean and temperatures skyrocket. The problem with the Boxster (and most modern cars) is that we've got fuel injection with a dry manifold. You can't just put a plate in after the throttle body. To add nitrous, you would have to put nitrous injectors and solenoids in each intake runner as close to the fuel injectors as possible. Then, you would need to either enlarge each of the injectors to flow enough fuel to get the correct ratio with the nitrous (likely resulting in a very rich condition when the nitrous is not flowing), or you would need to add another set of dedicated fuel injectors to work with the nitrous, which would make for some very crowded intake runners. Along with the injectors, you would probably need to plumb a dedicated fuel line and add a fuel pump. The stock system would not be able to handle the added load. To top things off, you would need to reprogram the ECU to, at the very least, retard timing during the nitrous application. Whew!!

And with all of that said and done, the only place you'd be allowed to do any competition would be the drag strip. PCA and SCCA prohibit use of nitrous in all classes, as do most other AX/track organizations. The folks at he drag strip would be happy to take your cash, being that lots of those cars are in the 1000+ HP range. I used to have a 71 Camaro (no nitrous, but I've worked with others who had it). It was like getting shot out of a cannon.

Rick V · 08-09-2008, 05:13 AM

Simply think s Nitrous as liquid forced induction. Would you add a turbo, or a supercharger to your car? If the answer is no, then there you go. As for the $500 system, go for it. I make very good money cleaning up after the people who like to cut corners. A proper system with the correct DME reprogramming would be ok but when you start dropping $$$$$ on bottle refills you will come to realize that it isn't cheep.
We, just for kicks installed a 250 shot on my sons Eagle Tallon, (it was on it's last legs anyway) Man that was a fun 150 miles.

The car is yours, the choice is yours, the results are yours too. I wouldn't do it to my car, but that is just me, and I would be staying in the "nause" cause I am a speed freak.

Brucelee · 08-09-2008, 06:12 AM

I suggest you peruse the IMS posts on this board. Given that their is a structural flaw that allows engines to greanade, personally, I would be loathe to experiment with MY engine.

Of course, we are happy to have you try it and report back.

Good luck and go with God.

dmcutter · 08-09-2008, 07:41 AM

I have no intention of being a guinea pig. Since the car has been out, what, 11 years, I thought somewhere someone must have given that idea some thought and I wanted to know the nuts and bolts of why it couldn't be done. I figured $500 was overly optimistic because nothing can be done cheaply to a P car. The key, as many have pointed out, is a properly designed system and it doesn't look like there is such an animal available off the shelf. I would prefer a turbo because I know that's been done and it would be usable on a daily basis.

RandallNeighbour · 08-09-2008, 07:52 AM

http://www.andysautosport.com/porsche/1997_2004_boxster/performance/nitrous_oxide/nitrous_oxide_kits/nos/

I'd prefer a turbo too. It's just 10x more $$$. However, it's under your right foot any time you want it and there's no bottle to refill.

HB. · 08-09-2008, 07:20 PM

Quote:

Originally Posted by RandallNeighbour

I do wish someone would do it though....

I will be working on it within the next month or so

jay3000 · 08-10-2008, 03:34 PM

Quote:

Originally Posted by RandallNeighbour

http://www.andysautosport.com/porsche/1997_2004_boxster/performance/nitrous_oxide/nitrous_oxide_kits/nos/

I'd prefer a turbo too. It's just 10x more $$$. However, it's under your right foot any time you want it and there's no bottle to refill.

Well. Looks like you've found your kit. The questions now are, where do you put the fogger? Where do you get a TPS signal? Where do you mount the bottle? Etc..

Surely this motor can support a 75HP shot. ( a honda civic can) If the bottom end can support 75 HP from a turbo or SC then this would be no different. The cool thing about EFI is that if the jets for the nitrous are slightly rich or lean the system will make up the difference in a matter of milliseconds. Another cool thing is that the engine likely has a knock sensor and can retard the timing if that should prove to be an issue.

Brucelee · 08-10-2008, 03:55 PM

Quote:

Originally Posted by jay3000

Well. Looks like you've found your kit. The questions now are, where do you put the fogger? Where do you get a TPS signal? Where do you mount the bottle? Etc..

Surely this motor can support a 75HP shot. ( a honda civic can) If the bottom end can support 75 HP from a turbo or SC then this would be no different. The cool thing about EFI is that if the jets for the nitrous are slightly rich or lean the system will make up the difference in a matter of milliseconds. Another cool thing is that the engine likely has a knock sensor and can retard the timing if that should prove to be an issue.

You seem certain that the Box can deal with the NOS hit. I am curious as to why you believe this?