My quest for ~300whp, keepin it safe

[Rookie84]

I've been searching around on what is needed to reach around 300whp with my s15 engine. I just wanted to double check for sure before I pulled any triggers.

I already have a FMIC, full exhaust w/ dp, and an intake.
I'm looking to purchase a z32 maf and debating weather or not I will need injectors. My car will be in drift events so I need a good reliable set-up.
If needed, what size injectors do you guys suggest? I was thinking 550cc.

Also, is the stock radiator enough for these levels?
How about an oil cooler??

[ripnbst]

Definately get injectors, and I'd also recommend an oil cooler if you will be tracking the car

[liv2drift045]

A z maf and 550's is about all you need (hopefully you upgraded your fuel pump when you did the swap). Actually the stock 480cc's will do fine. I'm just not sure about the stock maf. Also the stock radiator should be fine,but I would upgrade your fan. A lot of people say factory fans cool the most effieciently but I like electric fans. So maybe get some of those. Lastly, if you're going to track you're car, I'd recommend an oil cooling setup. Good luck. Have fun at the track.

[Rookie84]

So I guess I'm set with the stock 480cc injectors.
I wonder if anyone made it close to 300 with the stock maf?
is the s15 maf different?

I will need to upgrade my fuel pump though
Glad to hear that the stock radiator will do fine..
How bad is the oil cooling set-up on the stock SR?

[wootwoot]

Clutch fans always will flow more then air then almost any electric fan. If the car is moving over 30mph it doesnt matter. If you run the stock radiator you are retarted. It will NOT be fine at all. You will need an oil cooler too. You will need bigger injectors, you will need something to tune it very well. Why does everyone think tracking cars is cheap?!

you can do almost all of this for cheap though.

a 280zx radiator is a 3 core copper design, very thick and fits in there pretty decently. (I think its 280zx, search)

an rx7's oil cooler will work very well, just make your own lines out of real braided stainless stuff: 2nd or 3rd gen oilcooler. Cheap rubber whatnot fails!

Use a Walbro fuel pump, they are cheap and will be enough. Look into getting fuel cell foam, running lean because your fuel runs away from the pump sucks. The stuff isnt expensive anyway.

Run a welded diff. If its a track car the price difference between it and a high quality 2 way or something is not worth it unless you CAN afford it. To be on the cheap, skip it. A lot of Miata's run welded in the SPEC class.

good engine managment you cannot be cheap on.

injectors you can get Deatschwerks which I just spelled wrong, but they'll do fine.

300whp cannot be done on the stock MAF, it is beyond its voltage rating. There are ghetto ways to make it work but people dont do them with 240's since it is possible to use another MAF easy.

how can you say the stock baby baby worthless radiator is ok for tracking but recommending an oil cooler?? SR's dont run to hot under spirited driving for oil temp but coolant?.. Have you even looked at it? Single row super super thin thing. Worthless!


p.s. I bet you dont do any of this when you begin to realise how really expensive it is to track a car. Because this is NOTHING. You have way way way way way more to worry about

[Rookie84]

Whoa... calm down there.
I never said tracking the car is cheap ;)

the car has already been a track car without any problems on stock boost.
I already run a kazz 2-way lsd,
I have plans for engine management already...

I am new to the sr motors though.
But is 400 for a greddy oil cooler kit a good price?
BTW, I'm in korea so I have to get all of my parts from japan..
and 280zx radiator is out of question(too hard to source)
So I'll go for a koyo unit.
I plan to spend whatever its needed to get it done right,
I don't like taking short-cuts unless it has been proven.
Overseas shipping is a biatch!

I can always live with 280whp and skip the fuel pump and injectors..
Keep in mind I already have 480cc injectors.
Any opinion on this? Will the MAF hold up?

[sean350z]

Yea a Z32 maf is pretty much all you'll need. The injectors will flow to 300whp with a Walboro 255/HP. If you go larger injectors you'll have to do standalone as I don't know anyone who ROM tunes S15 ECUs in the states.

On my S15 MAF I hit 4.8V 275whp @ 15psi on your same setup which is not safe seeing when I tried to add more fuel via SAFC the MAF couldn't keep up at 4k rpm giving me a a/f that was above 14.

[Rookie84]

I'll probably end up going standalone with a power fc or this thing called samecu in Korea as they have done couple of s15's already.

So z32 maf and walboro 255/hp will be the two things for 280whp?
Any possibility of getting away safely with SAFC if I don't use bigger injectors?

[devonkyle77]

where did you get your motor? i live between your two listed locations, and would love to be able to pick up a motorset rather than have it shipped

[eastcoastS14]

^^ use bigger injectors i ran 740cc making 350whp also ran a enthalpy ROM tune idk if he does international orders

makin 350whp i had: 740cc inj
255lph walbro
z32 MAF
t3/t04 .63 ar 57 trim stage 3 wheel w. v-band exit
top mount mani
38mm wastegate
hks ssq bov
koyo rad w/ electric fans
phase2 intercooler
plus alot more stuff but those r the basics

[Rookie84]

I already emailed enthalpy and they don't do s15 ecu's yet...

I'm actually in Korea so I have to get all my parts from Japan.

[johngriff]

The Title of the Thread was 300hp.

IIRC it should be pretty simply done on a S15 engine. Everyone always tells me how great the MAF system is when turning up the boost. So start turning it up?

Do you have a shop in korea to tune the car as you do this?

You should make a decision about engine management before getting the 300zx air flow meter, it might not suit your needs at all. You might find a system with a MAP sensor.

[crazyikimasho]

The Title of the Thread was 300hp.

IIRC it should be pretty simply done on a S15 engine. Everyone always tells me how great the MAF system is when turning up the boost. So start turning it up?

Do you have a shop in korea to tune the car as you do this?

You should make a decision about engine management before getting the 300zx air flow meter, it might not suit you.

Agreed, definitely figure out your engine management first. Like personally Im not a fan of MAF so Ill either be running Haltech or Power FC DJetro. If you go that route theres no reason to spend money on another MAF ($100-150 used). Another good option if you decide you want to run MAF is to use a ROM tune such as RS Enthalpy. This route has worked well for several people here.

In all this, Im assuming you are running the stock S15 turbo (which should be fine). To be safe Id run 550cc injectors, so you can turn up boost and as men tioned previously, an upgraded fuel pump that you should do on any US chassis with any SR anyways.

A good tune via proper management, good fuel supply and some added boost should get you in that direction safely.

[Rookie84]

I meant to imply somewhere close to 300hp by putting ~300hp.

Anyways, I have a shop in korea to tune the car but I'm still wondering if I can get away (safely) with apex'i afc. I'm going to check with the shop if their ecu module has a map sensor or not.

[Rookie84]

Im going to skip the injectors for now and go with a fuel pump. If the duty cycle is really high, I'll get a re-tune with some new injectors later on...
I wish enthalpy can do s15 ecu's.

[liv2drift045]

You DO NOT need injectors for 300whp. I don't know how high the duty cycle will be but I know two people locally w/ s15 motors, stock turbo, injectors, z maf and fuel pump thats what they have (and a rom tune). As far as a radiator/fan situation goes, do you have an accurate gauge (and not the factory one either)? Watch the gauge, make your own conclusion.

[Wei240]

injectors rule of thumb is take the number and multiply by .66 or something, so 480's should be fine,
ems is more important (it'll determine if you'll need a maf or not)
safc kinda sucks imo, but it probably can get you to 300, (need a maf)

if you have a cat, it'll rob you of some power, not even sure what it's like over there...

[bshotts]

Doing some injector math....which I know has shown up here many times

cc single injector flow rate / 10.2 = lb/hr single injector

lb/hr single injector * # injectors (4 in this case) = lb/hr all injectors

lb/hr all injectors * max duty cycle (95% or .95 for SR side feeds) = lb/hr all injector capacity

lb/hr all injector capacity / brake specific fuel consumption BSFC (.55 to .6 for turbo) = total hp

So as Wei240 ^ said, it works out for a turbocharged 4 cyl to ~.65 * the injector size you are using:

480cc * .65 = 300 +- 15 hp
550cc * .65 = 350 +- 15 hp

You could always look into an adjustable fuel pressure regulator and raise the fuel pressure...make sure you use a higher flowing fuel pump in either case.

Fuel pressure/injectors calcs found here: http://www.rceng.com/technical.htm

Need a higher flowing MAFS to support further mods as well.

[wootwoot]

That isnt at the wheels and raising fuel pressure works but there are better solutions by far.

[johngriff]

The 550's are probably a good idea for 300, too high of duty cycles over extended periods will wear injectors quickly.

Oh. NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC NO SAFC

I found this the other night reading an interview:

What Is The Singular Aftermarket Product That Makes The Most Power?
ECU/ECU tuning. Most don't realize that tuning is the beginning and everything. I'm not talking about piggybacks either. People, piggybacks are f*@$ing jokes. Take them off your car and sell them to all the cheap-asses who buy crap from eBay. Always use a standalone or have the factory ECU ROM-tuned.

8ggalant: Can you track down who did the ROM tunes, that will probaby solve this guys problem.

[ronmcdon]

try to find out who are the reputable local tuners in your area and check out what standalone systems they work with. i like the aem ems, but it would be totally useless if nobody knows how to tune that over there.

[Rookie84]

I agree.
I will do that for sure.
I'm trying to find a tuner with dyno dynamics over here... I'm not a fan of dynojets.

[street240]

You can do 300 on your setup. But for the sake of safety go 550's and a maf. Not only that remeber that you can sell your maf and current injectors (they will go ) to offset the cost.

[jspecusa]

Z32 Maf
Fuel pump
Clutch
Boost controller
s14/s15 N/A throttle body
ECU(tuning is the key)

[liv2drift045]

8ggalant: Can you track down who did the ROM tunes, that will probaby solve this guys problem.

I am deployed at the moment so I can't.

If you(poster) want me to look this up when i get home, just shoot me a pm.