S15 SR20DET in KE55 first drive

[SRE-55]

Hey guys,

Well after 2 and a half years, the old girl was driven today for the first time with the SR in her. First off I must say I loved it

The only modifications on it so far are a front mount intercooler and a GKTech dump pipe and a 3" front pipe. No exhaust at this stage, just wanted to get it running first.

Now what I found is that it was boosting fine and reached a max boost pressure of about 6-7psi. That seems fair considering it's basically a stock motor. However, once the car reached around 5000rpm it didn't feel like the car was pulling any more so it just seemed natural to change gears. Is this normal for a relatively stock S15 SR20DET?

I did notice that the car was backfiring a little bit and a bit hesitant sometimes. Now only have a dump and front pipe on am I right in assuming it's the O2 sensor not getting an accurate reading?

Another thing I thought of is that the ECU was chipped and remapped from ADM maps to JDM maps. The car is running 98 RON fuel, but could this have anything to do with it?

Also one more thing on top, I have noticed that the silicon joiner I have coming off the throttle body is very soft and could be compressing in with the pressure and that currently as a temporary setup I have the wastegate hose connected to a nipple in the cooler piping close on the cold side of the piping.

If any one can shed any light as to what may be happening that would be awesome.

Cheers,

Anthony

[StuC]

my first thoughts were exhaust blockage, but you're only running the front pipes so that wont be it. 02 sensors are a 60,000km servicable item and are generally shagged - 80 bux for a new one so do it. PLugs fouled? CAS and timing set correctly? Start with the basics and work youre way from there. I suggest getting a decent silicon joiner and not a worn rubber one as they do compress/pop under load and vacuum. Also, the wastegate hose should be run from the stock position on the turbo - no need unless it has been tuned for it. If it is a JDM engine they generally run around 10psi from factory

[SRE-55]

Yeah I might give a new O2 sensor ago and might try and get a better quality silicon joinr. the cooler piping is getting redone very soon as well as the exhaust so hopefully that fixes it.

The CAS and timing settings should be fine as the motor was pulled out of an S15 and put basically straight into my car. Everything about the car is stock standard bar the cooler and dump/front pipe.

Cheers

[StuC]

just because its stock doesnt mean it is set correctly. check timing and position of the CAS. They are only held i by 3 grub screws and have been known to slip all the way to full advance/retard.

[SRE-55]

Yeah sure will have a look at that.

Thanks heaps mate.

[thu187]

Hey buddy.
I think the above 5000rpm thing is normal. I'm really not a fan of the SR20. It feels like it pulls like an n/a but others like that smooth delivery so each to their own. But yeah from being in mates' 180sx and s15's it really seems to not do much at the top end of the rev range.

I reckon jump on nissansilvia.com and ask the people on there.

[SRE-55]

Yeah I jumped on there and they've thrown around a few ideas too. Some are saying just run more boost if I want more top end. Would that sound about right for a T28?

[Toy77]

i have been in a few sr20's

the stock ones feel how you describe - a bit flat, but thick through the revs, more like a bigger NA motor.

The upping of the boost totally transforms it. makes it into the boosty kinda monsta you want.

cheers
Stew