Considerations for a motor running N2O

[Alpine TSi]

Besides the regular machining and precuations for building a motor are there any other things I should consider for a motor that is going to be running nitrous?(and for those who don't understand nitrous I mean NAWZ!!!111)

I am planning to almost always use pump gas on this motor as it is my daily driver and I really don't feel like having to run and get race fuel just to have some fun on the freeway. And please hold the comments back on this one but I have no intentions on using any other size turbo than my current EVOIII16G. I know it may sound dumb, but I don't want one of those uber laggy popcan swallowing turbos that are found on the local 500 and up hp cars. Plus the motor is only a 2.0. I currently enjoy full spool by 3700 RPM, mainly thanks to a perfectly ported head(thanks mike!). I don't want to sacrifice that in the least. But I do want to break 400whp, hence the spray.

I will be running some less aggressive pistons compresssion ratio wise in order to run 20-22 psi on pump with the appropriate fuel mods. I really want to only build this motor once as I am not loaded financially. I have already picked the shop the shop that will build it(they don't know yet), and want to go there with everything in hand and a good idea of what needs to be done to block to hold up with my plans for it.

Shane had mentioned getting the block o-ringed(or something like that) in order to keep all that spray in the chambers. I am not really sure what this does as I am an internals noob. I will be running a 50 shot that may be upgraded to a 75 if I decide it is needed.

Are there anyother considerations I need to look at inorder to get the most out of this block? Any and all POSITIVE feedback is appreciated.

Thanks in advance,
Matt

[slowbubblecar]

a little off topic but 3700 rpms to get full spool seems slow for a 16g since my 20g got it by 4000. That was on a stock 2g head, tb and intake manifold.

[Enes]

um, guys.. my 50 trim gets full spool by 3900 and that was full 25psi.
on colder days i've seen full boost as early as 3600, my t28 spooled at 2900 full boost 18psi.. honestly, i think you should upgrade to 50 trim, whe ever had them was pretty happy with them..

-E

[JET]

Yep, my PTE 50 trim got 23 psi by 3800 rpm. It really sounds like you need to just switch turbo's and not build the engine. 2.0's have made 430 whp on pump gas pretty easily with a 50 trim. I would definately go that route. Nash made 531 whp on stock internals, so you should be safe without building your engine too.

The head porting may slow spool a tad, but it shouldn't be much.

[Alpine TSi]

Well then maybe I have my number wrong, I was mainly looking at the torque spike on my dyno sheets and placing it there, does that sound right? I haven't driven it in a while so I am unsure exactly where it hits full spool. Hmmm... Maybe I will have to get it to run again just to see where spool is.

And the reason I am buiding a motor is because the current one is 177k old and every seal in that that is supposed to hold oil in, doesn't.

If I were to look at a 50trim I would probably look at a FPGreen as I am told that it is one of the fastest spooling 50trims out there.

Thanks for the input thus far.

[Shane@DBPerformance]

Turbos spool slower on a dyno, thats why the number seems higher than usual. You probably don't have to O-ring it, if you aren't going for crazy high race gas boost numbers, plus nitrous on top of it. Just try to get a good seal on that headgasket. If you are just going to run an AFC, get a socketed EPROM ECU so that some changes can made to the top few rows of the stock timing map.

[john]

I assume you are going with a wet kit right? Direct port or single nozzle? You should be fine with a 50-75 shot on a stock motor assuming you have ARPs and a new HG. I knew a couple kids who ran a 75 shots on a 14bs perfectly fine.

[Alpine TSi]

Yeah, wet with a single nozzle. And I will definately be doing ARPs and a Cometic HG.

[Raptor]

I agree with shane, for that level of boost/spray, I don't think the O-ring is necessary. Matt already has a socketed Eprom so he is good there. If you want, Matt, give me a call tomorrow, I have some ideas for you.

[Alpine TSi]

Cool, will do do doodely doo!