How far can you go before needing to upgrade the fuel system?

[M.Piedlourde]

Speaking hypothetically here...

In the RX-7 FD world, because the rotary is so vulnerable to detonation, you're only supposed to do a handful of engine/intake/exhaust mods before you start upgrading the fuel system.

I'm assuming that an SR20DET isn't as picky about fuel as a rotary, but how far can you go before you need to start putting in aftermarket ECUs, bigger fuel pumps, and better injectors?

Could the following theoretical setup manage itself OK with the stock SR20 fuel system and the stock ECU?


Redtop SR20DET
Aftermarket intake
Aftermarket downpipe
FMIC of your choice
Aftermarket exhaust

Assuming we're not messing with the boost settings, can you run the above setup without needing to mess with fuel?

Also, how does the stock ECU react to a BOV venting to the atmosphere? Not recommended?

I hope these aren't stupid questions, I did search.

[AKADriver]

That should be fine, with a good enough fuel pump (walbro, 300ZX, etc).

BOV venting to atmosphere is going to cause problems in any car with a MAF. I have no idea why people do it.

[Foxcolt]

I'm running an HKS 2540 at 8psi on stock fuel system, including fuel pump. No problems yet!

I've heard of people making 320hp to the wheels on completley stock fuel.

[Kookaburraz]

I've heard of people making 320hp to the wheels on completley stock fuel. Heard of...yeahhhh. Most people max out the 370s at 240-250 hp. No one is pushing them to 320 hp.

[Foxcolt]

Originally posted by Kookaburraz
Heard of...yeahhhh. Most people max out the 370s at 240-250 hp. No one is pushing them to 320 hp.

That's what logic tells me...I'm currently doing more research on it.

However a friend of mine did dyno at around 260-270 on 370's. So I'm starting to suspect the stock fuel system is capable of more HP than people think.

I'll get my car on the dyno soon and see what numbers I can pull with that turbo.

[fleaf]

a fuel pump is supposed to pump out twice as much an engine needs/requires, that is why you have fuel return line back to the tank. Hypothetically, you should be able to use the stock fuel pump on an SR, but most people don't just as a precaution.

[Dousan_PG]

Originally posted by fleaf
Hypothetically, you should be able to use the stock fuel pump on an SR, but most people don't just as a precaution.

its well known you'll blow your engine if you push it on the stock pump (or bump the boost)

ive known of 3 people who are too cheap to upgrade their stock 240sx pump and blew the motor.

ask any motorswap business. im sure they have a few customers who cut corners and are out on their ass now because of it.

im sure drift freaq knows folks a few too :)

[M.Piedlourde]

Originally posted by dousan36
its well known you'll blow your engine if you push it on the stock pump (or bump the boost)

ive known of 3 people who are too cheap to upgrade their stock 240sx pump and blew the motor.

ask any motorswap business. im sure they have a few customers who cut corners and are out on their ass now because of it.

im sure drift freaq knows folks a few too :)

Dousan, would you recommend going to a Walbro or 300ZXTT fuel pump almost immediately, if a person is planning on doing mods to the engine? Would it be best to just get that out of the way?

[Dousan_PG]

Originally posted by M.Piedlourde
Dousan, would you recommend going to a Walbro or 300ZXTT fuel pump almost immediately, if a person is planning on doing mods to the engine? Would it be best to just get that out of the way?

DEFINATELY! Its not even expensive. i think the walbro is like 100 bucks or something, its chump change

in japan i think the 180sx/s13/s14/s15 pump is more then the US 240sx one so it can handle more

anywyas, z32 is nice but i hear takes modification. side note: US GTR owners, when their fuel pump goes out, use Z32 pumps...

DEFINATELY upgrade the pump, no doubt. its cheap and you'll most likely never have to upgrade it again! most people wont come close to making more then it can handle. its definately something that you shouldnt cut corners on when doing the swap!



and for a 100 bucks....

if you cant afford 100 dollars when doing an SR swap YOU SHOULDNT BE DOING A SR SWAP!

[89s132b]

W3rd, that is the first thing I did. I also got a 300zx TT fuel filter for like 9 bux at Autozone.