THEhomelessONE

I'm planning on swapping my 89 crx hf. I have a donor 94 prelude with an h22a1, was going to get it REF'd then build an all motor h23v. Best I could realistically do is ~275whp max effort on pump costing thousands of doll hairs. I took a quick look at nitrous and it seemed like folks were saying it was a waste of time and these engines don't hold well to n2o so I let it be, settle for 11s NA. Obviously some bad info as I'm reading about stock B's getting near 400whp. Goal is 10's, I should be able to hit it with 325whp and 1800lbs including driver. H makes sense since I already have the donor but I'm mostly just curious. This way I'm still in the 12s na vs 14s(?) with a b16 with light mods. Closer to 400whp would be ideal.

Anyway, main point is, which stock engine is best for nitrous? It seems like H's like to have ringlands let go above a 150 shot or around 350whp. I'm thinking a b16 is the way to go. More ridged block, meat between cylinders, better RS ratio, etc. Also I'm not sure if it's the total HP that kills the engine or the size of nitrous shot. I don't mind going through bearings but definitely don't want to replace engines on a regular basis, so no exploding pistons or blocks cracking. Honestly I just started reading up on nitrous but I'm getting totally different feedback from just searching, mostly stuff 10 years old, hoping for some solid advice here thanks!

K7-1Ktrevor

K7-1Ktrevor

2kdrift

Thing I didnt like about nitrous was the cost/hassle of constantly filling up the bottle. IMO for something casual its a waste of money, if its stictly going to the track its more understandable

THEhomelessONE

Thanks for the info guys. Trickiest part for me would be getting the b16 approved by a referee. Reason I bought a complete running, smogged and registered prelude as the donor. I found it for only $1,000. Only obd1 b16 in the US is from a 94/95 del sol and they're going for over $4k near me. Doesn't look like an option for me. It's way harder to get a JDM engine past a ref even though I have a federal emissions crx. When I called the bar station, basically told me a JDM engine would be okay to swap in after the USDM engine was BAR'd and the JDM engine is considered a direct replacement. Even then, any emissions components would have to be transferred over. Going straight to a JDM engine to a ref would end up being at that particular refs discretion. Any CA emissions vehicle is now not allowed to have a JDM engine period. Lol should've done more research on even being able to run a b16 before making this thread, sorry guys. Stupid CA bullshit laws.

So I will be sticking to the h22a1, if it blows I'll drop in an h23v. IMO anything over a 100 shot should have a progressive controller behind it. With ringlands breaking, that's usually from not gapping rings properly correct? Maybe the piston or cylinder is expanding too rapidly under constant high pressures causing contact? What makes a turbo engine able to hold more power than nitrous? Once I have a second engine set aside and some free time, I'll see what a stock high mile but healthy h22a1 can take with supporting mods. Just wondering if there's someone here that's been there and done that with these H engines to save the rest of us the trouble lol. I know most racers and builders are hush about this kind of info, but with popularity dying down hopefully they can shed some light.

I get the hassle of maintaining nitrous. I'm lucky to have some refill stations not too far our, as well as many welding/gas suppliers if I wanted to keep a mother bottle at home and fill myself. Even off the bottle, she'll be a quick little car, I'd rarely use it but love knowing it's there if needed. Plus I don't need a ton of it like a heavy v8 vehicle would, I think I'll be happy with it. Worst comes to worst and I get sent back to a ref, removing a nitrous kit isn't a big deal, getting rid of a turbo system would be a huge pain.

Sorry for the huge posts, really liked the idea of the b16 though. With BMW's the non vanos m50 is kind of like out b16. Strong cylinder walls, very nice rs ratio, smooth inline 6, double valve springs. Guys in sweeden were pushing close to or over 1k hp and 9k rpm out of a stock bottom end 2.5l engine, many people in the US don't give it much attention and go for the m52b28's or something with vanos and they give out around 700hp. Swapped one into my e30, got it bar'd. Was going to boost it but ended up t-boning a guy who made an illegal turn in front of me. Ram 2500 right into the side of his axle.

turboLScrx

Aradin

It's not really the ringlands you have to worry about. That's just an old internet myth. People were breaking ringlands in the early 00s because they were "tuning" with garbage FMUs and VAFCs. They will last just as long as any typical cast Honda piston, which is further than most think, as long as the tune is in order and there's no detonation happening. I have messed with a lot of H/F series engines/setups over the years and I have only seen one bust a ringland. That was only because the guy had an injector that didn't flow enough to match the rest and ran one cylinder dumb lean while he was out beating it to death around town.

It's really not horsepower that is the problem. It's torque and how the power is delivered. In your average turbo setup for example 300wtq is generally the high end of the safe limit on a stock H/F series block. A good, efficient, high strung setup with a tubular manifold can use that torque and carry it into the upper rev range to make 400whp+ and typically it will survive for a good while. The power comes on much more gradually with less shock to components. Most of the power is in the higher rev range so the engine is doing things a lot faster so it's seeing a lot less time "stressed" as all the combustion events are happening so quickly.

With a straight nitrous shot it's totally the opposite. You hit the button and it's instant power and torque. Instantly shocking the whole rotating assembly with the increased power. You go from maybe 160wtq to 260wtq+/- on a 100 shot in an instant. Shock loads like that can very easily bend/break rods. It's even worse because most people want to hit the button low in the rev range for that immediate response. At lower RPM everything inside the engine is happening slower so the engine has more time to experience the brunt of all the forces going on.

If you're dead set on 150 shot then you will definitely need a progressive controller to shift some of the spray into the higher RPM range for engine longevity. Somewhere a bit beyond peak torque, say 6k or so. That and a really good tune. Nitrous is volatile, unforgiving stuff. One mistake, bottle pressure too high, etc etc and it's gonna cost you a block. With that said an H will take 100 shot no problem usually. Anything beyond that and you're in serious rod snapping territory. Don't forget all stock engines aren't created equal either. One may like 250wtq just fine while another may open a new inspection window at 200wtq.

K7-1Ktrevor

THEhomelessONE

Thanks for all the great info everyone. I'll stick with the H, have a shop hog the manifold and will go with a 4-1 header, don't mind the mid range loss vs 4-2-1.

Without going full standalone $$$$, what would be the best route for me to take tuning/ecu wise? Sounds like the s300 is the way to go, but I've also read people say hondata sucks etc without an explanation why or what they'd suggest instead. I honestly haven't even begun to search on the tuning/ecu side of things. Has been an extremely stressful last couple weeks and my head will explode lol. Fired at the worst time, hired the next day, off a week waiting for a call back, first day of work today, I AM BURNT. Thanks again guys, really appreciate it.

K7-1Ktrevor

hondalocal

LOL'd hard at this. "Inspection Window".

THEhomelessONE

Thanks for the help K7! Drove up past Oregon to Seattle a few weeks ago, people there are super friendly. Makes me feel like a dbag for being a Californian lol.

Haha I totally missed the second part.

K7-1Ktrevor