question about SR tuning

A place to discuss the systems and methods of tuning Nissan engines.
dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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my planned mods for the future include a S15 turbo, 550cc injectors, and a Z32 MAFS...will a SAFCII take car of all 3 of those as far as tuning goes????(im not looking to put down MASSIVE numbers...those 3 things are about all im doing as far as power upgrades go) or do i need to do ne thing else for extensive tuning...i wanna keep the car daily driven and reliable (i only plan on runnin 10psi on a normal basis as i do now with my T25)...as far as i know those 3 things are pretty simple as far as upgrades and dont need tuning other than keeping the fuel injectors from leaning out (and yes i already have a walboro low flow fuel pump...ive gone thru 2 high flows already...next pump is a denso or Z32)


USsil80
Posts: 1949
Joined: Sun Sep 07, 2003 6:21 pm

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yes you can change all those with the afc.... and you don't need any eletronics to change a turbo.... the afc is a good unit you just can't change many things around besides injectors and the mas unit.... and some moves on the fuel map... i think you will be a ok with just a afc... and happy with it to

SRdave240
Posts: 276
Joined: Fri Apr 11, 2003 8:16 pm

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SAFCII is perfectfor mild upgrades like the one you are planning. I'm doing pretty much the same thing.

Only thing that sux is we will be stuck with the crappy stock timing maps. Oh well.

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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well im not looking to change the timing on the motor...im shooting for 350-400HP to the fly wheel...shouldnt be too hard with that setup (and all the standard bolt ons ie:FMIC, catback, exhaust mani)

msaskin
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The biggest gains do come from timing changes however. If you look at most of the guys who have dynod 300+ rwhp from a T28, a majority have been running a ROM tune (JWT, secret services, etc...)

It's even more of an important thing out here on our crappy 91 octane gas.

~matt

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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i tend to run 100 more than 91...makes the car run smoother and smells ALOT better =)

Phax
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Car: Control dynamics

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dj_lennon_franz wrote:...and yes i already have a walboro low flow fuel pump...ive gone thru 2 high flows already...next pump is a denso or Z32)


Sorry for this being off-topic.

How did you go through 2 Walbro pumps? By high flow, do you mean the 255lph version? I currently have a Walbro, and I thought that it was a good pump when I bought it. Yet over the last six months, I've been reading a lot of things about them failing, and people having to 'hot wire' them to get them running right. I'm starting to think that my fuel pump might suck.

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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walboros are crappy fuel pumps...remember u get what you pay for in car parts...why do you think denso pumps are so expensive??? in the last year 3 of our main shop cars have gone thru at least 6 hi flow pumps...theyre just cheap pumps

also there is 2 version hi flow and low flow...the low flow seems to last longer...they both flow 255ml

msaskin
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dj_lennon_franz wrote:also there is 2 version hi flow and low flow...the low flow seems to last longer...they both flow 255ml


what you said is a bit contradictory, no??

what you meant to say is High pressure vs. normal pressure. The only difference is the HP version can flow the same volume (255lph) @ a higher pressure under higher load. where the normal 255 pressure drops off at higher load conditions, the HP version goes on strong.

That said, I ran a walbro 255 high pressure in my 400+ hp galant vr-4 for over a year with no problems, and am running one in my 240 for 3 months now without issue.

Also, before anyone says my galant may not have been driven hard, it made numerous drag strip passes as well as plenty of auto-x and road course abuse. Running at 100% throttle for the majority of a 20-30 minute road course lapping session tends to show hardware flaws with a quickness :)

~matt

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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anyways...no matt...there are 2 versions of the pump...hi flow and low flow...u can call walboro and ask em yerself

most people i know who use walboros hate them alot...im waiting for this one to die so i have an excuse to spend 280 bones on a denso pump that will last till armageddon

msaskin
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dj_lennon_franz wrote:anyways...no matt...there are 2 versions of the pump...hi flow and low flow...u can call walboro and ask em yerself

most people i know who use walboros hate them alot...im waiting for this one to die so i have an excuse to spend 280 bones on a denso pump that will last till armageddon


Lennon, saying "hi flow" and "lo flow" yet both flow 255lph makes no sense what-so-ever.

Walbro makes 4 pumps that are commonly used:190lph - P/N GSS242/250/278190lph high pressure - P/N F20000141255lph - P/N GSS307/315/317255lph high pressure - P/N GSS340/341/342

Trust me on this :)

~matt

TruboostPerformance
Posts: 310
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and SAFCII will be perfect, the SR is such a awsoem motor, it can handle all kinds of upgrades and with an afc to control fuel you can get so much horsepower out of it, on the other note I have been running a Walbro 255 for two years and it has worked flawlessly, an awsome pump

dj_lennon_franz
Posts: 496
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Car: 1992 240sx

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matt stop being a mr know it all

msaskin
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dj_lennon_franz wrote:matt stop being a mr know it all


I only do it when I'm right...if I'm wrong about something I'll be the first to admit it :)

Prove me wrong and I'll apologize profusely.

~matt

toledo240
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Joined: Sun Sep 28, 2003 12:42 pm

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i think your better off with a bigger turbo if your looking at those horsepwer numbers, with bolt on your going to have to boost the crap out of that little t28. go for something bigger like a t3 or something in that nature. What clutch are you running on getting these horsepwer numbers?

msaskin
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toledo240 wrote:i think your better off with a bigger turbo if your looking at those horsepwer numbers, with bolt on your going to have to boost the crap out of that little t28. go for something bigger like a t3 or something in that nature. What clutch are you running on getting these horsepwer numbers?


He said crank horsepower, not wheel.

While 400hp (~340rwhp) isn't too likely with a T28, he should have no problem hitting 300-320rwhp (350-375 crank hp) with it, albeit at high boost.

~matt

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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im not sure...i think it may be an aftermarket clutch in my tranny (i never pulled it off to check) the clutch is pretty grabby and ive kicked the crap out of it drifting and its still as grabby as the day i got the motor...i plan on putting a ACT stage 3 clutch in it soon though

Mikel
Posts: 84
Joined: Mon May 12, 2003 3:18 pm

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Matt's right about the fuel pumps.

Pressure is highest when flow is lowest. That's why the high pressure pump is desirable for turbo cars that use a rising rate fuel pressure regulator that increases fuel pressure with boost pressure. I've had one in my Grand National for 3 years with no problems, like all pumps, they are just sensitive to voltage variations. You need to make sure you're getting reliable power to the pump.

msaskin
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Amen to that :)

Lennon, have you just been installing them with stock wiring? I have mine hardwired from the battery (10ga. wire) with the stock power wire providing the trigger for a relay. I know ideally I would just replace the factory relay and make it a 1 relay system instead of 2, and I'll get around to that eventually :)

My pump gets battery voltage all the time, so pretty much a constant 12.5-14 volts depending.

~matt

TruboostPerformance
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Becareful with a really heavy duty clutch and a lot of horsepower, the SR tranny does not like to hold more than 450 and geat be beat up really hard on, 2nd gear goes real easy, broke 3 myself.

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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my 4th gear grinds...all the gears grind when im throwing the car around in turns...its just a typical nissan RWD tranny

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S14Life
Posts: 719
Joined: Sat Feb 15, 2003 12:07 pm
Car: b5 s4 stage 3, 2001 pathfinder, 91 s10
Location: bay area

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Yeah what exactly are you supposed to do when you hit your trannys peak power capabilities? You can't buy an upgraded tranny can you?

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

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yah...actually...theres quite a few people who make racing trannys for the SR...im pretty sure greddy makes one


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