Nitros for a Crossfire

[Zora1]

I am planning on adding nitros to my 84 TBI crossfire. I have done most of the external mods possible, like Flowmasters, K & N filters, 160 thermostat, etc, and want to add a 75-100 shot of nitrous for occasional use, like when I visit the track with our club a few times each year. My car has about 70K and has a very stout engine, and I don't feel I'll damage the engine if I use it correctly. Does anyone know a good brand or source for a system I can add myself? Looing for a wet system that will control the shot based on rpm's. Thanks!

 

[Ken]

Check NITROUS OXIDE SYSTEMS (NOS) for GM Nitrous Plate Systems. They have throttle body & early tuned-port systems that are designed for all GM applications and are 100-150hp adjustable.

System Requirements

The stock fuel pump should be adequate, but it should be capable of meeting NEW pump specs. If unsure, replace. Use only premium grade pump gasoline (92+ octane) or unleaded racing fuel. In many instances, a high-output ignition system and a free-flowing exhaust system may benefit performance. WARNING: DO NOT use aftermarket chips or other devices that advance ignition timing, as detonation may occur.

Actual performance gains will vary depending on the engine's condition and configuration. The system can be used on an engine with stock rods, pistons and crankshaft. However, at power levels of 140 and above, it is recommended that heavy-duty forged components be used.

 

[Zora1]

Thanks Ken. I checked out the website, though it did not have much info that described the system. I sent an email to Holley, so I'll see what they say. Does anyone else have any experience with NOS on 84's?????

 

[polish41]

There are a few on the Crossfire Injection Forum that have some experience with nitrous. Get on the forum and do a search. Also check out the tech section.

http://www.crossfire.webhop.net/

 

[WhalePirot]

Want a used one?

I'll call my pal who had a NOS system on his X-fired 406. He since went TPI and it might still be available.

Ed would be a lot of help with his expertise and do's and don'ts, too. I know he found that limiting when it was available was a great idea. I think he decided that, while sideways on an on-ramp!

I have a call in to him, now.

Mike

 

[Zora1]

Mike,

Thanks. I would be interested if he's still has the system. BTW, what's a 406?? I saw a show on '2 guys garage' where they added a NOS system to a C-5. I liked the way it was controled by RPM rather than just hitting a switch. Seems like that would help prevent the sideways problem you mentioned.

 

[Mad-Mic]

how much money do you want to spend? with rpm control your talking about you need a msd 6a box. i think you can add a setup for nitrous rpm band that you are talking about. if not i know they do make nitrous % boxes. basically at a certain rpm X amount of nitrous shot is given till you achieve the rpm range for the full shot. the guys that race in prostreet classes use these for launches.

you can add upto 1/2 amount of HP your motor comes stock with. so 235 hp divided by 2 comes out to 117 HP you could add with a shot of NOS and be safe on a stock motor.

a 406 is just a 400 motor bored over .030 i believe it's still a 350 based sbc

hope this helps but my knowledge of nos is limited compared to supercharging.

 

[Zora1]

I was hoping to be able to find something for $4-500. I like the idea of keeping the car farily stock, and having the nitrous for those few times I do go to the strip. Appreciate the info.

 

[Mad-Mic]

i'm sure you can find a 75-125 dry shot with throttle plates that go between the throttle bodies and the actual manifold. i know NOS or holley used to make them. they should still be out there. this kit costs about 400 bucks or so if i remember correctly.

 

[WhalePirot]

No callback from Ed on his NOS system.

The 406 appears the same externally, as the 350, but is a different block. True, it is a .030 over, 400.

 

[Mad-Mic]

the only difference in the block is not external but internal. it's just meated out more so the swing of the 400 crank won't hit the lower end of the block.

 

[Zora1]

Thanks to all that have posted. I believe I found on the Holley website that they do make a NOS kit for the crossfire. I'm going to call Summit and see if they can get me one for my new year's resolution to add a little fire to the old 84!:xmas

 

[WhalePirot]

Check the quality of the Holley, first. I hear that NOS stuff is quite nice, and haven't heard a lot of great things about Holley, lately.

Mike

 

[Ken]

Hmmm... I just thought of another company that may be able to help you. Have you tried ZEX yet? Check 'em out, they're even in your part of the country.

_ken

 

[Zora1]

Thanks Ken. They don't make a kit for the 84', but I ordered a catalog and will see if I could assemble one.

 

[CorvetteArchives]

Darn It!!

I know that either CorvetteFever or Vette did an article on this in the past few years but havent been able to find it again in my back issues! The set up was fairly easy and the plumbing was very well concealed under the hood....the only way you'd know was if you saw a nice carbon fiber bottle in the hatch!

Will make effort to find that article again but cant promise for sure.

 

[JonM]

From the Crossfire site

 

[mynewc5]

Man, in all honesty, I wouldn't sink any money into the crossfire. JMO, but those motors were a mistake, and GM knew it as soon as they released it... Should have been called "caughtfire injection" because that's the only thing they did really well. Swap the motor out for an LT4 if you want some real power, don't mess around with that garbage setup..

Doug

 

[JoBy]

don't mess around with that garbage setup..

Doug

Do you have any personal experience of the Cross-Fire, or is that something you heard from someone else?

Ther CrossFire engine respond VERY well to Nitrous. The intake is restictive, but it is big enough to get the nitrous in. It is exactly the same engine as the 85 exept for the intake. It also has TRW forged pistons.

12.73 in the quarter from an almost stock Cross-Fire with a 125 shot of NOS is not that bad.
That Corvette had the following mods: 1.6 roller rockers on stock heads, flowmasters, high flow cat, 125 shot NOS, drag radials,and 3.73 gears. The intake was still stock.

I agree that the LT4 is a better engine, but it would be expensive to do the swap. It would be better to sell the 84 and buy an LT4 Corvette in that case.

 

[oldace84]

I don't know if this will be of help....but I feel it will....Have you checked out the CrossFire Forum...don't know the URL....but they have ton's of info on the CrossFire Vette's...I know they helped me alot.....maybe someone can give you the URL for this site...
Try it...you'll like it.....believe me....
tony