1999 ACR Big cam or Nitrous kit

[Venomess]

I have a 1999 ACR with 41k miles on it. It currently has smooth tubes, headers, no cats, Borla S-Type mufflers and an X-pipe out the back. With no tune done and id like to get more power. Im looking at doing a cam kit (lifters, springs, push rods) but I have no idea what size cam or who to get the kit from. Or... looking at maybe just a 150hp shot of nitrous with a progressive controller (to make it more safe), bottle opener and warmer with a 15lbs tank. Which would you guys go with and suggestions?

[Fatboy 18]

Subscribed, always wondered about Nitrous, think it looks cool seeing it purge, like the idea and added power but also agree I don't want to blow my engine! I dont know much about it as it only ever seems to be fitted to drag racing V8s overhere?

[BrianACR]

Sent you a PM.

[nrs1]

I have a H/C car Gen 2 and a Blower/N20 Vette; here's my opinion:

If you're looking for more power for racing (1/4mi, or 1/2 mi) N20 can be done safely with a complete wet system like from Nitrous Outlet. Lots of safety switches/controls built in to ensure safe operation, but you have to buy the add ons. The Nitrous works great for planned events, but if you want it for just cruising the streets, its a pain in the ass. You have to make sure the bottle is installed, heated, purged etc. But you shouldn't store it in the car with the lines pressurized and heated. So depending on where you live, it may take a while to heat to the right pressure. If you're in a hot climate like AZ, you have to take the bottle out, so it doesn't over pressure in the summer. Also, some areas, the Nitrous is still scarce due to the Florida Nitrous plant explosion. AZ is one of those states where it is very scarce (the shops have to drive over to CA to get it). Like I said good for pre-planned outings.

A H/C will give you power all the time, and preserve the ability to use the power on the road race track. But it is much more expensive than the N20 system. Probably around $6K-7K depending on what you do and where it is installed. Also, not sure you would like the gains/$$ with a cam only approach, unless you do the work yourself.

Another approach is to do FI (Roe or Centrifugal Supercharger about the same cost as H/C). Will give you the Nitrous HP, but it will be available all the time, and it will come in smoother. Nitrous will tend to blow tires off at a 150 shot, unless you start running drag radials. (which you might need to hook up anyways with a S/C anyways).

I use the Nitrous in 1/2 mi racing and it works ok there. The only issue is the rate of depletion in the 1/2 mi. with only a 125 shot. I only get about 6 runs on a 15lb bottle, since you can only drain it about 1/2 way or so, before it starts losing pressure. The other problem is that it hits hard, which makes it difficult to manage traction. With blower only, I can modulate the power delivery to match the tire condition, track condition and weather. Nitrous is kind of on or off. The progressive will help, but the ramp will stay wherever you program it.

S/C may cost more up front, but I think it will serve you better in the long run for instant HP and everyday driving.

[Fatboy 18]

Good info, thanks for that.

[nrs1]

Good info, thanks for that.

Fatboy 18, since you're a road racer, I'm sure you know you don't want a S/C. It will generate too much heat. You could install nitrous to mess around, but it wouldn't be practical to use it on the track, unless you were really racing and just needed to get by that guy on the straight :drive: It's why my Gen 2 is NA

[BrianACR]

When doing a heads and cam, what's the most lift and duration you can get without having to worry about valves contacting pistons? Springs are good for 0.625, stock gasket thickness.

[nrs1]

Myself, wouldn't venture to guess and give you misinformation. I would suggest contacting the engine experts e.g. Greg Good, Dan Lessor (VSP), Dan Cragin (SPT), Arrow, etc. Too expensive to be guessing/trial and error, labor-wise and reliability results :)
My cam specs are:

236/242 .615/.621 @ 112 deg w/1.7 rockers
.050" milled head; .027" head gasket

Springs/valves are not stock

[BrianACR]

Thanks for that info. Maybe one of the guys you mentioned will chime in here...

[nrs1]

They are not typically on the forums, you'll probably have to call the shops.

[99RT10]

Do both, heads and cam for good power all the time. Then add nitrous for a fun little boost. :D

Call Greg Good to pick the cam profile. Really great guy to talk to.

I have a set of Gen 2 heads, Ported, ready to bolt on. PM me if interested.