sr20det tuning pros help

[nismo200sx16]

I just finished my rebuild on on my sr. I changed my set up a little bit and have lost all my mid range power. I run a gt2876r , deatschwerks 740's, nismo rom tune, z32 maf, crower stage 3 cams 272. hks springs , and a knock off greddy intake mani. their is more but I figure thats all you will need to answer my question. my old set up was almost the same as it is now. only differences are used to run nismo 740's , stock intake mani , and hks 272 stap 2 cams. I have also added a safc2 now to tune for the slight difference in the injectors. the car has very little power below 6k rpms. I can watch my boost gauge and I have about 10 psi at 3k but no power. the rpms slowly climb till around 6k and then the thing screams. in third gear traction loss at around 65mph. but the thing is a dog till those very high rpms. are my cams screwing me? the old setup would pull like nothing else through the entire rpm range. and my air fuel ratio i know is to lean but around 12.5 when it is dogging through the rpms. timing is set to stock 15 and plug gap is .029. pleas help explain my turd sr.

[lok]

why did you switch injectors?

the tune was for an off the shelf rom tune right?

[jspaeth]

Seems bootleg to be honest. Just ditch the ROM tune and SAFC and get a standalone.

And why would you get Deatschwerks in place of Nismo injectors?

Sounds like a tuning issue.

[nismo200sx16]

jim wolf rom tune was for nismo 740's z23 maf. long story about the injectors but to make it short they are in my s14 with a ka-t now. injectors are close to the same. but not exact. upped the fuel pressure to 50psi at idle. correcting with the afc on low throttle to 26% and haven't messed with the high throttle settings. air fuel ratio is lean at 12.5 in the lower rpm but when it gets to 8k its in the 10's. seams like when it starts to pull hard it starts to run rich. I am guessing because of the jump in air flow. the car started with the deatsch injectors with the old setup and pulled hard all the way through the rpms but ran lean like it does now. I had no way to tune and took the nismo injectors out of my s14 while I was working on it. now I can tune for the injectors so I am using them again. haven't even started to try to tune for wot yet because of this problem. and I have no way to see what the timing is doing.

[jspaeth]

In all honesty with injectors that big and a Z32 MAF, and for the power you appear to be going for, you should take the car to someone that knows how to tune it properly....it's worth the money IMO

[BoostinGST]

sounds like something is messing with your timing, maybe when you changed the cams you didnt line it up correctly? i suggest selling the safc and taking the car to someone that can dyno tune it with the eprom ecu. also just because they are both 740cc injectors does not mean they will have the same pulse width.

[nismo200sx16]

the tune is really close. I tuned my ka-t the same way. and it has the same setup basically but has a sc6176. but it has a jim wolf rom tune for the same stuff. 740's and a z32. and I fine tuned it with a afc2 as well. I understand the tune is not perfect yet. but have only driven the car 3 or 4 times since the rebuild. I have just bin driving around getting the low throttle settings perfect. which they are now. have only gone wot a couple of times. I dont know whats killing the power. wot correction is at 0 so far. may be I should try adding fuel and see what I get. could be their is knock that I cant hear in the low rpms and the ecu pulls timing. then when the rom tune adds tons of fuel in the top end like every one that has a jim wolf rom tune knows it does it stops knocking and putts the timing back in. thats really the only thing I can think of. engine sounds clean though I cant hear any knock. but that dosent mean its not their.

[slider2828]

Do you have a wideband logger. If not... don't bother.. Keep your eyes on the road nad it is safer for everyone... Trying to drive and tune and correct = fail... Get on a dyno if you want to tune it yourself.

[nismo200sx16]

cams are in correctly and base timing is spot on. I know the lag time on the deatschwerks injectors is a little more than the nismo. but its not that much. and no one any where near hear does any nissan tuning.

[nismo200sx16]

plx m500 with wireless data logger

[BoostinGST]

Originally Posted by nismo200sx16

cams are in correctly and base timing is spot on. I know the lag time on the deatschwerks injectors is a little more than the nismo. but its not that much. and no one any where near hear does any nissan tuning.

looks like its time to take a trip.

[steve shadows]

Just sounds like tuning to me.

Power FC + Plane ticket + Discounted tuning rate from me

ps: The car will be A LOT more fun with 264 cams.

272 is overkill. They belong on cars that rev out to 9k

[nismo200sx16]

yeah I want to try some diffrent cams. I got a good deal on them and are the same specs as my hks ones and I liked the way the car ran before with them.
an fc would be nice. but the thing is the car worked with the injectors before and pulled good through the rpms. may be I could try swapping injectors from the ka-t and see what happens if more time tuning does not help.

[s14teen]

Ok sorry for this but af ratio is perfect burn at 14.7 to 1 and to break this down for you that is 14.7lbs of air to 1lbs of fuel. This is perfect for emission but as far as for performance a 12.5 af mixture is rich not lean and on a turbo car that is about right. perfect is 13.0 on a turbo it allows for cooler piston temp. as well as creates better exhaust expansion. lean would be anything over 14.7 on you af. If i was you I would look for leaks on your iac as well as anywhere on you intake manifold. two I would double check your timing try doing it by putting a spark plug wires on number 1.

[nismo200sx16]

I started this thread to get help from tuning pro's. not people that think an af of 12.5 is rich on a car running a fair amount of boost

[V8slayr]

don't want to be redundant but it sounds like the cam timing to me. with the minor changes you made w/ your setup seems like it should feel the same. I had the same problem when I put my SR together, and I even double checked the cam timing and thought it was good. turns out when I took it to a local performance shop it was the cams, I was a tooth or 2 off. It's kinda easy to mess up the cams based on the factory service manual, but enthaply has got his own simplified cam installation process on his website.

[rb25_s13*CHUKI]

What the problem seems like to me is timing... My sr does that with bad timing too so yea... As for your setup i dunno maybe standalone??

[NINJAS14]

Dude the same thing happened to me, all I had to do was switch out my exhaust bearing and all my power came back.
I got mine here: http://kalecoauto.com/index.php?main...products_id=10

[nismo200sx16]

I am going to have to pull the valve cover and triple check the cam timing. highly doubt I screwed that up. but their is a first time for every thing. and I will just order up a new exhaust bearing to be safe. smart ass.

[steve shadows]

who did your tune?

Deatshwerks want to run 0.00 injector lag time correction

because they are rebuilt SR injectors (most commonly from deathwerks)

If they use a KA body, then the tuner would have to change the lage time accordingly.

This is why a power FC is nice, you can change lag times instantly with commander or data logit.

[johngriff]

You had the same rom tune before and after?

What is the AFM setup like in the AFC?

Should be 1 in 1 out.

[nismo200sx16]

thanks for the help guys. I found that the problems I was having were caused by timing being retarded to much. thread can now be closed