JadeGreenEF9

Even though I don't really agree with the thought of nitrous being "forced Induction" I figure i'd posted in here so the "na is best" dudes over in All Motor don't get butt hurt.
My set up is..nearing completion. And im wanting to run a decent nitrous hit(100-150). I need insight though, no one around here runs nitrous on cars.My set up is as follows...

p72 head, no port work. RM genII springs and retainers. BC spec 4 cams. JG 65mm TB. AEBS intake mani. Hondata intake mani gasket. Probably going to order stock size aftermarket valves, in fear of the oem ones melting. Good idea?
OEM head gasket. ARP head&main studs, ARP rod bolts. B18a Block has a GE block gaurd. micropolished crank. all new honda bearing. eagle rods. Greddy header. Pistons im about to order are 82mm JE 11.5:1's. Im picking up a Holley wet kit monday.

My goal for the car is 200whp on a mustang dyno, off the bottle. Now onto the dilemma. I understand how Nitrous isn't like actual forced induction at all. But I know it does create SOME increase in cylinder pressure, and the jolt of receiving it all at once, will it be too much for stock sleeves bored to 82mm? The car is gonna be fully tuned on crome, with 310's or 450's, and the necessary timing will be pulled for however big of a shot I choose to run. At first I was worried about melting a piston or a valve. But I think the JE pistons will hold up to however big of a shot I plan to run(probably no bigger than 150). And I don't know how well stock valves hold up to such a big hit, so im considering aftermarket valves. But I really would rather not buy them and have to get them cut in and ****. But i'll do what I have to do. So the only thing im really worrying about is the sleeves cracking. I don't have the money to sleeve the block, im a broke *** college kid with a part time job. And boring it smaller for the fact of having room to go bigger if/when it goes isn't really of a concern. LS blocks are cheap as hell so im not too worried about that. But if the motor would be safer with an 81.5 bore on nitrous, then I will do it. The car will-not be constantly sprayed, im building the car to haul *** around turns. Make the occasional trip down the 1320 to see what it will do. And have the bottle for highway runs vs. cocky kids in SRT4's. The car will have a safe tune, and I plan on beating the car whenever its driven. I know safe and 150 shot of nitrous don't really go together, but im hoping to make it work. ANY insight/suggestions will be really appreciated. 82mm safe? should I go smaller? stock valves too weak? am I on crack even thinking about running this set up?

JadeGreenEF9

...please? I've been searching for dayssssssssss on the subject.

zexxbo

i would run the 100 shot, but i would suggest you find where you can maybe skimp a little or save more out of your next paycheck and go directport rather than singlefogger. definitely a good idea to replace the valves for aftermarket, id reccommend skunk2 or ferrea. the motor will definitely be safer at 81.5mm but i still wouldnt call cramming a 100 shot into a high compression ls/vtec "safe".

JadeGreenEF9

Correction! I just found out the kit im buying IS a direct port kit!!!!!! 100 bucks, complete aside from bottle. I was gonna buy it either way, and his forsale post said "lineS" so I kinda hoped it was, and it turns out it is. So thats awesome. Anyone on here HAVE a 82mm motor on nitrous with close c/r to mine? I really wanna talk to someone who knows nitrous GOOD. I want to find out exact increase in cylinder pressure. I've come to find out from reading all over, that it is "Very little". But still, could it be enough to crack the sleeves? Mainly, having the increase all at once instead of gradually brought on like a turbo car. Also, what power differences are lost between 81.5 and 82? Is it not even enough to notice?

Zeimbo, thanks a ton for replying man. I guess i'll go with aftermarket valves. I always stood by the "aftermarket valves are STUPID on N/A motors" because there is really no need for them, but in this case im a nitrous n00b that doesn't know the toll it will take on stock valves. What is the highest shot you can get away with on stock valves without them melting?

Wickedsol94

Big bore ls/vtec, high comp, and bc 4 cams, and only expecting 200whp off the bottle? Sounds like 220-240whp off the bottle is more like it.

Sick build, i wanna see some pics.

boosted92

Make sure it's an EFI direct port kit. A lot of direct port nitrous kits are designed for a low fuel pressure setup, in the 6-10 psi range like what you see from a carbureated fuel pump. If you buy one of these kits, you'll have to build a standalone fuel system which will definitely add to the $100 cost of the kit.

I would just stick with 81.5mm or even 81mm if you can. When you spray 100 horsepower worth of nitrous at say 4000 RPM's you're adding 131 ft-lbs of torque. If you spray that at 3000 RPM's you're adding 175 ft-lbs of torque. There is a lot of cylinder pressure created by spraying nitrous especially at low RPM's, so I would run as small of a bore as possible. You arn't going to notice a difference between 81mm and 82mm bores on your motor.

And on that note, I don't understand why zeimbo thinks 100hp worth of nitrous wouldn't be safe on a very mild 11.5:1 LS/VTEC build. Before I went with turbos for my Mustang I was running a 363" small block at 12.5:1 compression. It made 600 RWHP naturally aspirated (yeah, that's about the same specific output as a 200 WHP b-series ) and I would spray as big as a 500hp hit into it. Almost as much nitrous as the motor made naturally aspirated. Run some race gas, knock out some timing, run colder plugs and you'll be fine.

zexxbo

i would not bore to 82mm on stock sleeves. especially since youre daily driving it and have a high compression ration. going to 82mm, you wont even see a power increase maybe, a very small maybe, might see +-5whp depending on a bunch of variables.
figure it like this, if you build the head and do it right, you can use the head on a turbo or all motor application and it will take abuse. youre a lot less likely to float a valve if your head is built.
i dunno, im sure you can run 100shot on stock valves and not melt them. however, im not sure how long you could lol. i mean you can put a gt42r turbo on a bone stock b16 and boost 20lbs, but the motor will blow up after 2 minutes ya know.
youll be around 200whp. i mean youre running relatively conservative headers for a crazy all motor setup, i would also do 2.5" or 2.75" exhaust to the muffler with your set up. my friend has a similar setup but higher comp and bigger bore (sleeved) and hes only putting down 230whp.

JadeGreenEF9

Yea, the header is weak. But its what is on my car. I want a better header, but gonna have to sell some more **** to buy one. Also, the exhaust is a Greddy SP which kinda sucks. I have a ton of **** that NEEDS TO SELL (DHR fully built LS head with crower valvetrain, arp ls head studs, skunk2 ls intake mani, misc. b series turbo ****, stock bore SRP 9:1 pistons, want it?) but Cincy is broke dick haven, and everyone rocks D series with 4000 dollar wheels and JDM quarter panels....... I've been reading up on valves, and seeing that they are safe up to a 125 shot. True? Im a broke *** college student, so saving 175 on buying valves, plus another like 150 having them cut in would be rad. Im thinking of just going 81, since boring it wont see that many noticeable gains, and the risk that come with it aren't worth it. Plus I can just beat the expletive out of my motor, and having some meaty stock bore sleeves will give me more peace of mind. also, I plan on doing all this on pump gas(93). I plan to have my tuner pull whatever timing neccessary for the shot, when the nitrous is armed.

And yea its an EFI kit. Im pretty stoked on that deal. looks like im gonna have to order some different jets then(comes with 150's). And to wickedsol, dude if it dynos 2xx im gonna be psyched. I just want it to run 12's, and its going in a sub-2000lb EF hatch. Hopefully my goal can be achieved.

THANKS for all the help dudes

zexxbo

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted92 &raquo;</TD></TR><TR><TD CLASS="quote">
And on that note, I don't understand why zeimbo thinks 100hp worth of nitrous wouldn't be safe on a very mild 11.5:1 LS/VTEC build. Before I went with turbos for my Mustang I was running a 363" small block at 12.5:1 compression.</TD></TR></TABLE>

your block in your mustang is also made from iron or steal, which tend to take a little more abuse than hondas bottom ends . everyone knows that ls/vtecs have a shortened lifespan, even with the type r oil pump and the oil line, etc.
spraying 100shot into that baby with high compression pistons is not something i would use as a daily driver. if it was a car that saw less use, i wouldnt think much of spraying the 100shot.
they are safe up to 125shot, just like stock sleeves are good up to 500hp. doesnt mean that they will last long tho. i just kinda got the feeling that you wanted to set your car up for reliability while still retaining power. btw, your car might be boggy when youre not on the bottom because your timing is gonna be retarded. and also, youll prolly be in 12's with your motor off the bottle assuming that youre in a sub 2000lb hatch. run some deflated mickeys and i think youd be in 12 seconds. my friend had a similar setup and he would roast evos and wrx's on the freeway

JadeGreenEF9

The car will not be daily driven. Maybe during summer time I'll drive it for a few days at a time maybe even a week, until driving a totally gutted, fully caged, loud *** car with 13/11k coilovers and a fixed bucket seat gets annoying haha then i'll switch back to the Vdub daily beater.

Also, the car will hardly ever be sprayed. I plan on BEATING the car on backroads, hopefully a few track events. And only use the bottle for the "damn I really need it" cases. And maybe a couple times down the 1320 just to see what it will do. And the ecu will only pull timing when the nitrous is "armed", well thats the way im tuning it anyways. And yes, I do want the car to be reliable while still mainting power. But im also doing it on a budget..which kinda sucks.

JadeGreenEF9

derrr. I meant its gonna be tuned to where it pulls timing once the solenoid is open. Lack of sleep, and I posted that like like 3 in the morning

92redhatch

if you plan on making 200whp on motor go with the 440cc's. I would run aftermarket ss valves because i melted my stock valve on a 75 shot.

harhoosh

B20 Block, stock (sleeves, pistons & rods)
PR3 head, stock (valve, spring, retainer, cams)
340cc injectors & Boush pump
110 turco racing gas

Two stage nitrous 190HP (single fogger for both)

11.02 @ 127 mph

alex86

Don't forget a fuel pump, upgraded ignition, and Nitrous safety equipment such as an MSD Window switch (which turns the juice on and off a set rpms) and a fuel pressure switch (which shuts off the N20 if the fuel pressure gets too low). Valves and a good clutch are a good investment too. You should really start out at a lower shot such as 70 or 80hp till you learn more about keeping it tuned correctly so you don't blow it up. You should also check your plugs after spraying too. Good Luck!

JadeGreenEF9

Harhoosh, THAT is what im looking for. You had no problems burning valves ?

Im gonna run a walbro 255, msd blaster coil and probably an msd 6a or sci since I supposedly need to with the msd 2step controller.

harhoosh

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JadeGreenEF9 &raquo;</TD></TR><TR><TD CLASS="quote">Harhoosh, THAT is what im looking for. You had no problems burning valves ?
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No, i dont have any problem with stock valves. and i am going to go with bigger shot this time (230 to 250)

I will see what she can do

N.Y.C.E.

the set up you are thinking of doing will work out fine! 150hp shot on stock 82mm sleeves with 11.5.1 is not the issue you should be concerned with. with this set up i suggest running a nitrous progressive system so you can ramp in the 150hp of nitrous without shocking the bottom end with such a hard initial hit. we have run stock gsr engines with 150 direct port and never had an issue ignition timing and fuel octane is the key with nitrous setups and will determine the outcome positive or negative

JadeGreenEF9

is it better/safer to go to 81 if I can? Im just STUCK on what kind of pistons to order at this point. I want the motor to be as safe as possible. And I found a really good deal on some 82mm 11.5:1's. I just dont know what to do. And N.Y.C.E, on a 150 shot, you think the valves would be ok?

Civich22ybrid

That set up would be fine. I would run your valve lash on the loose side to help the heat on your stock valves. MSD, window switch, retard box (nice to have), 255 pump, run good gas (110).....Use a wide band, learn to read plugs. NGK 8's would be good...Good luck!

JadeGreenEF9

110? So this is impossible on pump gas? Or should I just run race whenever I srpay. that is confusing me as well

Civich22ybrid

You're going to have to run race gas when you spray. You can use pump for motor with a little tuning. But you will need to drain it or use it, then add good gas for the track etc. With 11.5:1 I wouldn't use pump gas for any shot of nitrous

JadeGreenEF9

err damnit, that blowss. I found some used stock bore srp 11.0:1 pistons for 100 bucks locally, im thinkin about picking them up. since it seems to be safer than boring it out?

ramhorn15

Pick those pistons up (11:0:1) srp, we had a crx with a direct port system that had a 85- shot ls-vtec 11:8 compression, bored .20 over with stock valves and head. It went 12.8 @ 115 traction problems (bad traction problems)

JadeGreenEF9

thanks for the reply man, it really helps. im definately picking those pistons up. hell yeaaaaaaa