LNF and nitrous
 

Before I get flamed for not posting this in the nitrous section, I want you to hear me out. The old threads are mostly for the LSJ and the "all you need to know about nitrous" or whatever the name of the thread is, is coming up on 2 years old and there's been some huge improvements in tuning and software since then. For example does HPT 3.0 make nitrous any safer on the LNF? I've always though a wet shot is safest, but I'm only thinking about using a 35-50 shot. I've seen cold side/preMAP and MAF set ups on MAF relocated cars. I'm making around 400whp, is a 35 shot safe on the stock bottom end and 4t45e? Obviously a bigger and better turbo would be a better idea, but I cant afford that with the 70 cent exchange rate..

The only real changes between 2.24 and 3.0 is the scanner is faster so is way better. The problem with running nitrous on a stock LNF bottom end is the torque spike. A turbo gradually delivers the torque to the wheels vs nitrous is a major torque spike. If you were gonna run nitrous I would do a specific tune that runs a bit richer and has the appropriate amount of timing pulled.

What turbo do you have by the way? Maybe a meth kit and new tune would be a better choice

I was thinking about running a nitrous specific tune for the strip, or asking my tuner if we can use one of the unused pins on the ecu for it like trifecta used to do: and I have a gt2871 .63a/r. I'd be using a window switch and a wot switch after 3000rpm (I'd be getting pretty much full spool by then anyways) and cutting out before 7100

A progressive controller?

That actually seems like a really good option. Do you think a wet shot would be safer to run? I've heard it's the best way to use nitrous on FI cars, but the gms3 LSJ's used dry shots and I've really only seen dry kits used on our application

Yes use a wet shot it'll keep the engine from going lean. I'm worried about the 400hp plus the shock of the nitrous kicking in on the rods. A Progressive controller will solve that but then you get close to ZFR money

It is entirely possible to run nitrous on your setup, but the other posters do express valid concerns for the health of your stock bottom end. Also, your poor transmission (goodbye 3rd gear!)

Another thing to be considered with nitrous is that it is jetted for HP, and if you spray at a low rpm you will see a much higher torque increase than the rated hp increase. So it is possible for a 35 shot to pump up your torque by like 75, and that you need to be very careful with adding to the stock engine and transmission at your power levels.

In your tune you will also need to be VERY certain that you are removing ANY Intake Temperature related or similar timing adders. You wouldn't want to be making 400whp on some ethanol fuel and then go hosing down the intake with freezing nitrous, only to have your intake temps drop dramatically enough to scavenge over to the areas of the IAT modifier tables that actually ADD more timing advance.

Yeah, that's what I'm worried about too. I'm building the bottom end next fall. And then if I have the nitrous set up, I'll just ditch the 35 jets for 75 and swap my gt2871 for a gtx3076, I already use a t3 manifold and external wastegate

I would go with the 7163 or 257. I've made threads of both you should check them out

Will do, im sort of stuck with Garrett right now because of the 4 bolt housing. Once I build my engine I'm aiming for around 600whp and trying to get into the 10's

You mean a t3 flange?

Yeah it's a t31. But 4 bolt compressor housing
https://cimg2.ibsrv.net/gimg/www.cob...19b2043c4.jpeg

I'm in the middle of building my transmission, I bought a raybestos red forward clutch pack, 3.91 gears (as opposed to 3.29 stock) and a team green LSD insert. I might get my tranny cryro treated while it's all apart, but I'm not sure if there's any point after it being driven 80,000miles... I'll be tuned on 93 or 94 (ethanol isn't available in Canada). I'm not so worried about torque because my window will be after 3000rpm, and I'm actually expecting that I lost a bit of peak torque going from a k04 to a gt2871 and it help up fine before I had a good tranny bushing. But yeah I'm trying to stay away from bending rods or blowing ringlands. I'll size the jet according to my dyno results. I'm just waiting on the dollar to rise enough for the $700 edelbrock wet kit on summit to not be over $1000CAD

A 257 is a t3 flange and I'm waiting for him to dyno but I'm expecting close to 500. I'm in :ca: too so I know your fuel issues but 94 isn't that bad compared to :usa:'s 91

Yeah, our 94 is actually pretty good. And yeah, I saw an lsj roll race a gtr with one of those and win on 1320 video. Do they have much lag? I should be looking for a bigger turbo I guess because it'll boost ramp itself and the automatic holds boost through gears. I just like how quick the gt and gtx turbos spool, but I want the nitrous for more on top. I might look at the DBB 6262 or a big gtx for later in the build

I didn't realize you had gone Single Scroll. yeah, you probably wont have the torque problem.

It's a big heart breaker going from the immediate response of a twin scroll down to a single scroll. You pretty much erase about 2,000 rpms worth of torque advantage.

A gt2871r should spool plenty fast on an LNF prob pretty close to stock

That's what I'm thinking, it should push more air at a lower rpm than the k04

I had the 2871 on for a summer and decided to go to an s257sxe. Since I did that I ended up doing pistons, rods, neutral balance shafts, valve springs, 2.4 throttle body, upgraded timing chain tensioner and I'm swapping to a built 4t65e-hd. I'm starting to think about running nitrous on the new build

If you do buy the nitrous express turbo kit so you can just use the spray on spool