nos + LA 360 = ?

[Mooky]

I have a 1975 plymouth arrow that is a sideline race car project that I am slowly piecing together to run with my boys... I have a 1971 360 with a decent set of worked heads and a 509 purple shaft...runs a weiand 180" intake and has an adjustable rocker assembly...big oil pan and good pump....I have a holley 190 electric pump and regulator for fuel......am running a mallory unilite dizzy..and using a recon 850 double holley vaccum carb atm...I know I will need better rods and forged pistons for the nitrous, but any of you run a 360 on nos...any pointers or should do's...I have never run nos so all I know is what I read and hear and see form other users...any help will be greatly appreciated and I am sure I can speak for my car as well.

 

[Budnicks]

Mooky I ran N2O for years, the biggest problem I usually see is people don't run a dedicated separate fuel system for the N2O alone, separate fuel pump, regulator - bypass style preferably, separate fuel lines & filter, you can use the same cell or tank, you should have a way to back out some timing when you hit the switch or at least back off the timing 4 or so total degrees at the point of application, keep the bottle warm so you can keep the pressure up depending on what size & style of kit you plan to use you will need multiple bottles, if you plan to make several full passes with N2O, start out fat on the fuel side & creep up/lean out on your tune up in stages until it's correct for the conditions, it will help to save parts in the long run... Mount the bottle so the pick up tube is facing at the rear of the car & at a slight downward angle the fitting for the hose should be pointing straight down after bottles are in the bottle brackets...Good quality Balanced bottom end with Forged Pistons & Rods or Aluminum Rods, quality head gaskets w/good head seal, fully charged & well functioning battery, manual arming switches so you can over ride if necessary & run every thing thru relays to keep the voltage spikes from effecting your ignition & battery capabilities of keep charged up, "if you use stock rods make sure they have quality rod bolts" & bearing at the least, a hot spark coil & ignition is also a must (your going to put a bunch more fuel into the combustion chamber & need a hot ignition to be able to burn it all completely).. There many style of kit, there are kits that are under carburetor plate kits (easiest), spray bars plumbed rite in the intake manifold (hit hard & easy to tune), & down nozzles in the combustion chamber (really for professional only)& Fogger kits plumbed in the base of intake runner like FI nozzles (popular with most big hp kits) point the nozzles at the intake valve contacting the seat as close as possible or towards the top of the runner if you can't have line of site to the valve, to get the best flow & performance, there are also dry kits no added fuel if you have a fuel management system like EFI computer types... Always have an adequate supply of fuel going to the Solenoids, always have a couple of full fresh bottles have plenty of jets or pills for adjusting you system... There are a few companies out there that make electronic management systems I would highly recommend using 1 if you plan on using more that 75-100hp N2O kit..... Happy Moparing

 

[Mooky]

well heres the deal....I had a edelbrock victor pro plate system for a tunnel ram given to me for moneys owed...brand new in the box...10lb bottle and all the wiring books and all else is there....did some reading and I am sure i can put the motor together that will handle it.....just wondering if i should use belt drive timing or gear... and the timeing issue weather to use a digital comp box for spark or skip the carb and go holley fuel injection...plus this is a programable kit 350 hp 2 stage with man trigger and over ride features...and how many bottles would a guy through ata a day at the track?...say 10-15 runs.....just don't want to scatter on the first run...guarantee I will learn the hard way but would like a few learning curves before the car does


thanks for the advice I have it bookmarked for reference....any books or site you would recommend?

 

[Budnicks]

I have had some bad luck with belt driven timing I had a Jessel timing set, it was great as long as I didn't get on & off the N20, I snapped a belt & destroyed an expensive engine in the process, I used only gear drives after that (I'm not saying they are bad, I just had a negative experience & went back to what I knew worked with out any issues)... I would go with a program-able tuner for sure with a big kit, I'm not going to recommend any specific 1's though... Do your research get the one that fits your exact needs... With a 350 shot maybe 2 passes safely per 10lb bottle, you will probably run out during your 3rd run or not have enough bottle pressure (900psi) to maintain the full power, it really depends on how & when the system or multiple systems come in & how long, at that rate consumption 15 passes man that's a lot of passes on the juice 7 bottles safely maybe 5 it won't take a full 10 lbs to refill them because they won't be completely empty just not at the desired bottle pressure, with a tuner you may get better rate of consumption than I did... I haven't ever run the Holley fuel injection couldn't comment on them, there is a company F&B Throttle Bodies they are great with electronic fuel injection contact them they can build you a great system you can send them your kits & manifold they will set up a great EFI set up for a competitive price & they are great guys to deal with, I haven't used them for quite a while now but they are still in business, I'm sure... Fowler Injection & BDS are also a great resources also an Enderle or Hilborn hat on a tunnel ram works great (I believe they also make EFI versions of them now), I have used them in mechanical FI configurations & N20 apps, they look very cool & work extremely well... What kind of budget are you dealing with? FI can be costly to get set up, but are great once you get past the initial price, multiple race carburetors set ups, aren't exactly cheap either...

 

[Mooky]

I was planning on a msd 7 or 8 digital box depending on the size requirements ... and I was already thinking gear drive timing, and that confirms that for me...I have heard other negative elsewhere about the belt drive systems..was just feeling out waters for people such as yourself that have used them....I miss wrote previous comment on the amount of usage on the bottle...that would probably be a whole summer for me ..so sounds like 2-3..cool..at 6.49 a pound and hazard fee I can handle that.....I'm not trying to cheap out but don't have a wad of cash for just the engine fuel management either...I do have a set of polished holley 660 performace carbs off from a big block tunnel ram with very little usage so far..both tuned and run with rocket brand fuel...now if it helps..the car I am building is a 1975 plymouth arrow..2x3 chassis full cage ..shortened 9" with 31 spline axles and moser gears 4:88..locking diff...4 link with pan hard bar and coil over shocks...has a mustang 2 front with a heavier strut..mid plate with front stabilizer rod and mount....the trans currently in it is a beefed a904 short with b&m kit and a 3200 stall...that can all be changed...it currently has a 10 wide 29 tall hoosier tire on the back with in a min tub running ansen magnesium bean slots with fenton 4.5 wide 14" rim front.....has home made wheely bar but not finished or mounted currently...I strpped it down for a new paint and thought after getting the kit...what the hell it might be fun...the engine has a forged crank with recon stock rods...Ima have to get forged pistons and maybe boost for the Ibeam's...the car is literally the size of a dodge omni, maybe a frog hair longer...and it is still a door slammer and would like to keep it that way if I can manage.....I just don't want to hit the button and wad the car up within the first 40 ft on the first attempt ;) The wife would literaly kill me ..and I am not just saying that.....I actually plan on making her the driver..hopefuly..she enjoys racing and runs our v8 chevy mini van in street tire 1/8 pretty good......just has a problem staging to this day and I still smile till she tries to smack it off my face;)

 

[Budnicks]

With a N20 management system you can make it come on softer lower percentage of flow or hit hard with full pressure, sounds like a really fun car, I had an ex Pro Stock Arrow many moons ago, it was lengthened 4-6"s actually, short wheel base cars & N20 can be a handful, a looser converter designed for N20 usage & a trans-brake will probably help stage the car a little easier.. Start out at test & tune & small shot & creep up on the tune up, if she isn't use to powerful car on slicks, it sounds like it will be easily in the 9's you will need all the appr. SFI rated safety equipment, fire-suit & a competition license, maybe even chassis certification, I would put a 10'-12' chute on it too, it's a good way to straighten out a car if it gets crazy (like short wheelbase car can do) & fix the wheely bars for sure...