I have a 94 a4 with 112k on it, all stock except for SLP intake flowmaster catback and Hypertech. I was wondering what if any n20 i should run. I dont want a to mess up the car since this is my daily driver, and I have heard that every 100 shot ( Icant remember what it was) you have to retard your timing 2* and I didnt want to mess with getting an ignition box for that but any opinions here would be great.

 

If you are worried about dependability, then I would go with a 100 shot. I wouldn't cut corners though, run the safety devices and it wouldn't hurt to do a compression and cylinder leak down test to make sure the motor is healthy. There is a good sticky at the top of the page.

 

Honestly, nitrous is NOT for you.

Your gonna be a pity-party 3 months from now when you blow it up. Everything you do, other than basic bolt ons, to make more power out of the car, is hurting reliability. Spraying 100 more horsepower through it, without wanting to do any of the safety equipment on a daily driver, is a grenaded engine (And one more person to complain about how N20 blows engines) waiting to happen.

You CAN NOT run nitrous without an ignition box, window switch, WOT switch, and Fuel Pressure safety switch. Well, you can, but then it blows things up, or blows intake manifolds apart, and bends throttle blades on the conservative side of things.

Nitrous is an excellent way to make more power, reliably, and in a very cost efficent way. But you can't get spoiled and cut corners. You wouldn't put a cam in and not tune the computer, so why would you run nitrous without its required safety equipment?

Honestly, my best advise I can give you is this: Research, Research, Research. And in the mean time, stuff all your extra money away. Find yourself a beater vehicle to daily drive (If something would happen to your Camaro, and in my case, so your not letting salt rust your car apart all winter long) for $1000. Once you have something to fall back on, then do something such as nitrous. Going fast, and going fast reliably are two entirely different things. You dont want to cut corners, and especially not on a vehicle you need to have up and running/reliable.

Waiting another year to run 12's wont kill you.

And dont get pissed off, just take it for what its worth. You dont want to have a awesome clean daily driver with nitrous ... and a blown motor.

 

I would also suggest a simple compression and leak down tests be run before purchasing a nitrous system. This will verify that your motor is healthy enough for the extra cylinder pressure nitrous is going to produce.

If everything checks out fine, here is what I would suggest.

Safety features:
Window Switch $129
Fuel Pressure safety switch $49
Remove Hypertech tuning...(advances timing) Free

I would keep the shot to 100 or under and alway use good gas.

Now on the ignition box...I can get you the Mallory 685 for $245 this is only $116 more than the window switch alone.....they are easy to install and will improve NA performance also.

 

I didnt say I wasnt going to run the safety's and as it is a daily that is the main thing that would be my concern. I was just wondering what limit would be on a mainly stock engine with my milage. Thanks Ray for all your info Ill let you know what I decide.

 

I would do the mechanical checks on the motor first as Ray suggested. On a stock motor, I would say a 100 shot would be the safest route and people have gone up to 150 as well without any problems. I wouldn't go above a 150 shot though.

 

... Yea I guess I was a little **** about it ... Im just saying, if its your only vehicle, your best off not to run the spray through it. That aside, LT1's will take a 100 shot fairly well. And MANY on here are spraying 150-175 and even a few using a 200 shot. Most of the people running a 200 shot on the stock hsort block though are running some dual stage set up, or progressive controller (Which is pretty awesome btw)

 

Ok... just to let you know this is not my only vehicle, just the one I choose to drive daily. My other vehicle is an 87 camaro SC with a newly built 355 with an 750 cfm edelbrock (just incase you were wondering). So needless to say the LT1 gets better gas mileage. Anyways, when I do the compression check what should it be for me to consider running some N20. Also next question, if you do have to retard the timing 2* every 100 shot (or whatever shot it is) if I only run a 75 will i still have to do that. Thanx for all your help guys.

 

With the compression check, you are mainly looking to see that the cylinders are pretty close to each other. Shoebox has a good writeup of the procedure: http://shbox.com/1/4th_gen_tech2.html#compression_test If you are only going to spray a 75 shot, you shouldn't have to pull any timing.

 

Actually you will have to pull timing. You have a Hypertech, and they add a couple degrees to the spark timing tables in the PCM. Or at least I thought they did.

So you will probably have to pull 2-3* for a 75 shot. The rule of thumb is 2* per every 50 increase.

And sorry for busting your ***** on it, I thought it was your only vehicle ...

 

or just remove the hypertech program when spraying

 

I think you could get away with a 75shot and pull no*, arn't most kits sold are kinda dummy tuned, a little on the rich (safe) side.

 

That's what Iv'e been told also, but why chance it?

 

yea, i was going to return the hypertech to stock when planning to spray but does any one know if i can return the timing to stock while keeping my shift firmness setting and rev limiter setting. Dont worry I wont be spraying till redline its just seems to run so much better at that few hundred extra rpm. i guess i can just mess with my hypertech to make see if i can do that. Thanx for all your help guys and Dave i will contct you when i am ready to purchase.

 

Sure, you can take out the tune part and keep the other options down loaded.