Thread: Tuners help needed

Good call Ben I missed those commas. It's been a long night/morning

it won't be at 25 at torque peak. Torque peak is at about 5000-5500rpm and timing in that area of the map based on this airflow is only 13-15*. The 19* base seems to be really happy there based on the airflow it is seeing. I am going to knock it down just slightly.

Torque peak is really weird though because on the dyno it shows it dropping off. Normally the torque curve is flat, and doesn't start going downward until 7000rpm on high boost. Low boost it is flat all the way to redline on the log manifold.

I think 17* may be the sweet spot. Don't wanna detonate at all. I am going to take the car out tonight and see if I can get it to run good without any boost leaks. I thought I didn't have any boost leaks before, but I was wrong. Hopefully I get all of them this time! Shows my log manifold spooling way way faster than the new setup, this dyno was terrible.

Good news is we had a lexus ES300 dyno. He had a boost leak half the size of a BB, my buddy shawn plugged it with his index finger, and the 2jz managed another 45whp on the same boost pressure. This car uses a map sensor so I am guessing boost leaks can hurt power a hell of a lot more than I initially thought.

I honestly didn't think it would affect power all that much, but I will have to see when I get back on the dyno.

Boost leaks are no joke... Now did he make 45whp peak on top of what he already had as the peak or did it give the 45whp throughout the powerband?

There is a thread about this, where one of the forum members patched up a boost leak and got around 30whp but only thought the power band not at the peak.

I can't seem to find that thread for the life of me, someone with better searching skills please try

Jp fixed a small boost leak and only gained spool. But imagine how inefficient your T28 or T25 would be trying to make 15psi with a boost leak at only 50% efficiency.

The ES300 gained tons throughout, the 45whp was at peak on a 71mm turbo. It was a big precision turbo. 45whp at the 900whp level though is so small lol.

Found it... He gained a lot!

http://www.sr20-forum.com/turbo/17326-look-what-little-leak-fix-can-do.html

I see that now. I wasn't paying close enough attention to your log. It seems you might be safe at 17-19 degrees base timing. Maybe...

Well, I think I fixed a few leaks. Car running pretty strong, I lowered timing to 17* per Ben's suggestions. I instantly notice that my idle is about 1000rpm higher lol. I figured it was because it was cold, but the car warmed up and idle stayed around 2000rpm, dropped to 1500 or so for a bit. I am going to get right on that.

I haven't gotten a chance to see what the TPS volts is at. I think I backed it off but not sure. The datascan will tell me lol. my DMM batteries are dead.

The response of the engine is very very noticeable. The throttle is much more snappy now, and the midrange power out of boost is very nice. Watching the boost gauge hit 7-8psi before 3500rpm is really nice. I think I can hear just a hint of surge but it is very very quiet. The blowoff sound was missed for sure though. Since this one big leak was fixed the blowoff can actually be heard now. It is much louder than before... actually I don't ever remember hearing it before lol.

The turbo sound is awesome. You hear that thing spinning all the time. Any touch of the throttle at any rpm results in the turbo pitch increasing.

Rolling on throttle at 4500rpm or so in 2nd the car hits the rev limiter so silky smooth-like that I thought the clutch was slipping! The power delivery was so smooth, It was like the tires were on ice. Awesome. Way better than when I dyno'd it. Hell, when I dyno'd it the car wouldn't spin 2nd when rolling on the throttle. It would only spin if provoked during a shift.

So I took the car to the onramp...er racetrack. Normally about 130-135 is what the log would do at the end. 135 was in the cold around mid march. Well today I had to let off because I nailed 145 and that was as far as I wanted to take it. 65* out, so nice and cool. I need to get this thing back on the dyno. It feels much better, but I will need about 4.7V on the maf to hit around 400whp.

I don't wanna speak too soon, but it seems that a "little" leak fix can do more than just increase spool. We'll have to see the numbers! Appreciate all your help guys, wish me the best!

drove the car today. Blew a coupler off giving a ride. Car felt good, but not as good as last night in the cold. I will check soon to see if it helped with power. If not, I will try putting the VET cams back in and see what happens.

Is there any reason why switching the intake cam would NOT cause a power gain? I shouldn't have any reversion, but the power gain from switching the intake cam were negligible at best. Maybe 4-5whp on the top end. I figured the bigger intake cam would improve power by a lot, but it seems like the exhaust cam is where the power is made. I bet the VET exhaust will do even better.

Who knows? Maybe the VET cams are just better unless huge turbos are used. I did everything I could in order to prevent reversion so I could use big cams. If the VE cams don't make any more power, I will switch back to the VET cams and see what happens. Maybe they will work better?

I will pm you tomarrow.
cheers .

It shows here not hitting peak torque til 5000rpm, but with the leaks (the ones i could find) fixed the car hits 5psi at 3000, 10 by 3700 and 15 by 4000rpm.

You can see the power drop on the top end and this should only happen if the turbo is not happy and VE drops off. On the VET and log manifold setup the top end just kept going and needed more revs.