ineeedmorespeed

OK. I've got a 355 with vortec heads, exhaust, etc. most of the details listed in my sig.

I want to run a nitrous shot in excess of 150.

I'm wondering other than the usual stuff (plugs, fuel delivery, etc) what could I do that would strengthen my engine for nitrous? i.e. piston upgrades, heads, etc...

In other words, what does an engine built for nitrous consist of??

I'm planning on adding 1 3/4 headers, 3.42 gears, afpr, 24# injectors, and a cold air intake not to mention suspension stuff like LCAs and relocators BEFORE I install a wetkit starting at a 100 shot.

Soon after (once $$ permits) I'm going to add a HSR, 58mm TB, underdrive pulleys, Be Cool radiator and all that other fun stuff. I just want a vehicle with good streetability, maybe 450 fly hp before the n20. I want my motor to last, and if there is anything I can replace or upgrade now to help ensure that I'd love to hear about it.

Thanks in advance!!!!

Sonix

iTrader: (1)

looks like you've got the forged pistons. That's good.

Better rods/crank (forged) are also usually in a nitrous motor.

Colder plugs, secondary fuel system for the nitrous (not as hard as it sounds)...

Biggest thing IMHO, is opening up the ring gap. If you used 4.5 thou per inch of diameter, go up to 5.0 or so. I think my rings were gapped at .016" out of the box, and I opened them up to .022" or so, in case I ever used nitrous. There's an article somewhere on the web showing how opening up your ring gap a few though gives such a small increase in area for blowby, that it's basically a moot point... Specially compared to butting your rings and popping off a ring land.

ineeedmorespeed

Thanks for the feedback...I'm definitely going to look into the rods/crank upgrade. If anyone has any suggestions on this that would be greatly appreciated. Thanks again!

Sonix

iTrader: (1)

you're re-tearing down the motor to build it back up for the nitrous?

I assume the pistons/holes are still good, so you're not buying new pistons.

Buy the crank and rods based on 650HP then, since 450HP + 200HP nitrous.
Some H beams with APR bolts, and a forged crank, balanced, that should be fine. Look at Ohio crankshaft, or locally, since you'll probably get it balanced by your local shop.

ineeedmorespeed

How much do you think those parts would cost? What about labor?

I'm only gonna do what is sensible. If we're talking about a 4-figure job than I might just take my chances. I mean, if I'm spending that kinda money I might as well just look to getting a whole new motor.

Sonix

iTrader: (1)

labor? what are you kidding?

oh, 01 lincoln... So you don't turn the wrenches yourself?

It'd be close to $1000. I don't think it's totally necessary. Forged pistons (which you have), and wider ring gap should be ok. I'd make sure the rings are gapped right, but thats a whole rebuild right there so....

ineeedmorespeed

I do a little work myself but I don't know too much yet, I'm only 20. Changing the crank and rods seems like a lot of work. I'm sure I'll get around to learning how to do all that stuff myself...til then..someones gotta help me!

Time2Fly

A camshaft with a wide lobe separation angle.

Sonix

iTrader: (1)

not to stir the pot, but I remember reading an article from car craft where they tested a few different cams on a ford 460 motor, with a 200HP nitrous shot. the nitrous cams added like 2HP at the top end, but lost 15HP throughout the range.
Anyway, didn't make much sense to me, the whole concept of a nitrous cam sounds "right", and this was a ford 460, but take it for what it's worth I guess.

ineeedmorespeed

Hmmm. This talk of wide lobe seperation angle loses me a little bit. lol. I was looking at a cam w/ a 244deg dur and .510 lift and 108deg lobe seperation. I'm not sure what the lobe seperation should be on the cam I have currently. I believe it is something lik 238 dur and .450 lift...

Sonix

iTrader: (1)

Is that a roller cam? Seems pretty tame as far as lift goes..?

LSA does a lot of things. A wider LSA is easier/possible to tune with computer controls. A wider LSA flattens out your power band, yet it's not quite as high. So a short LSA would have higher peak HP, but not as wide of a torque band.

More exhaust duration is usually what a nitrous cam consists of. That and wider LSA I guess.
Check out comp cams website, it's easy to navigate. Grab one that meets your needs.

ineeedmorespeed

I'm not that educated on cams but I believe the .510 lift cam is a hyd flat tappet and the one I have currently is also (Crane Hyd Flat Tappet Cam, .450 lift, 238 dur.).

How much +/- in these areas if need be would you suggest?

Again, I don't know a lot about cams in general, so please be patient! thanks...

On the Comp Cam website I found this:

12-415-8: HYDRAULIC ROLLER: Street machine with 125+ nitrous system or small supercharger. 2200 stall with lower gears.

Duration at .050: 224
Intake Valve Lift: 0.502
Exhaust Valve Lift: 0.52
Lobe Seperation: 113°

Here it is on Summit for $245.95:

COMP Cams Nitrous HP Camshafts: CCA-12-415-8 - summitracing.com

I'm going with 3.42 gears along with 1 3/4 headers, 3 1/2 flowmaster exhaust, intake, 100+ n2o wetshot, all that fun stuff...

How much HP do you think I would gain just upgrading from the .450 lift flat tappet cam I have now to the nitrous cam listed above???

xpndbl3

iTrader: (5)

for your basic 100-150 shot your forged pistons is fine. I think that personally after that amount you're really looking into spending some cash on 4340 cranks, rods and quality forged pistons, ie JE nitrous pistons. Realistically I'd just toss a 150 shot onto your combo now and call it good. A window switch wouldn't be a bad idea, just like a nitrous filter, fuel pressure safety switch, bottle heater, pressure guage, etc etc.....will all add up to over $900 to build a reliable system. Your 700R4 probably won't last, nor will your 10 bolt rear end, so this is a double edged sword.

brodyscamaro

Bottle heater is 100% necessary

ineeedmorespeed

Agreed. I've seen several "intake explosons" from under-pressurized n2o.

evilmonkeyracin

you should be fine, how often are u going to run nitrous on this motor? remember to back off your timing 2 degrees for every 50hp of nitrous though, we are running 100hp of nitrous on a 1995 Chevrolet Cheyenne 1500 with a 5.7l with 110,000 miles on it with a cam one up from stock, with colder spark plugs, headers, 3:90 in the rear with a auburn posi unit, and we havent had any problems but we only play with it , the nitrous gets shot maybe once a month for maybe 3 quarter mile runs.....

Sonix

iTrader: (1)

make sure you know what all is involved in going to a roller cam, from a flat tappet cam. You need more then the cam, just make sure you know that.

That cam will give you more power over your .450" cam for sure. Probably 20-30HP.

ineeedmorespeed

The n2o will probably be used on the weekends, during the 4-5 summer months here in MN and sprayed for all of maybe 5-6 runs each weekend. I'm not doing this religously, so it won't necessarily be every single weekend. I expect to go through at least 2 bottles a month during the summer, in the off-season she hybernates in the garage ;0)

ineeedmorespeed

By the way. Thanks for all the solid information. Hopefully this post will be as helpful to others as it has been to me!

brodyscamaro

You'll go through way more, trust me...

izcain

I think NOS says that @ a 125hp shot it will last only about 7 runs or so.