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I got 280kw at 16psi at 6000rpm. I had no cat. If im correct u had a cat in ur exhaust system?.....Get rid of the cat and I can almost guarantee you will see around 20rwkw gain and response gain as there is less back pressure on exhaust wheel.

Edited by adam999111

I've got something like this

http://justjap.com/store/product.php?productid=18066&cat=&page=1

Will order a mid muffler prob tomorrow or fri and see if I can fix it all up before I go to Japan then make appointment for when I get back for another run. Just wish it wasn't 2 hrs to tuner. Driving through the city with a twin plate was a nightmare.

How far back was your dyno sheet Adam?

Edited by t_revz

I got 280kw at 16psi at 6000rpm. I had no cat. If im correct u had a cat in ur exhaust system?.....Get rid of the cat and I can almost guarantee you will see around 20rwkw gain and response gain as there is less back pressure on exhaust wheel.

Based on what exactly? There is barely 5hp difference between my car with the exhaust on vs off...

I've got something like this

http://justjap.com/s...066&cat=&page=1

Will order a mid muffler prob tomorrow or fri and see if I can fix it all up before I go to Japan then make appointment for when I get back for another run. Just wish it wasn't 2 hrs to tuner. Driving through the city with a twin plate was a nightmare.

How far back was your dyno sheet Adam?

My dyno sheet is on page 292. that power and psi i stated was actually at 6200ish rather than 6000, mind you its did make just over 290 before some timing was backed off.

Based on what exactly? There is barely 5hp difference between my car with the exhaust on vs off...

Based on the laws off physics.. In an Ideal world nothing after the dump on the turbo, will obtain the best results performance wise. any restriction in the exhaust is going to result in power loss, thats inarguable, its just when the gains don't become significant enough to worry about. Please dont get hung up on numbers, it might not be exactly 20kw... As with your exhuast, it must be a good free flowing one

Edited by adam999111

^^^

On the same time you are also running an external gate. I've also made 290rwkws on 19psi peek at 6200rpms at 17psi on the same turbo externally gated off the turbine housing. It some appears the external gate has greater gain used on stock exhaust manifold.

I've got something like this

http://justjap.com/s...066&cat=&page=1

Will order a mid muffler prob tomorrow or fri and see if I can fix it all up before I go to Japan then make appointment for when I get back for another run. Just wish it wasn't 2 hrs to tuner. Driving through the city with a twin plate was a nightmare.

How far back was your dyno sheet Adam?

that's quite a restrictive cat once it warms up

Only when it's warm? ^^^

when the core heats up, becomes an exhaust restriction, this easily can be done with a few squirts on throttle on full song.

yeh sorry i keep forgetting i have ext gate and t_revz is internal, but he will still see gains non the less without at cat.

Will also see some decent fines from the EPA if caught :)

Soon enough it will be free flowing. Just have to find a suitable muffler to compensate noise and bring it down quite a bit

I might be biased here, but HKS Super dragger, it's dead quiet man. Seriously not much louder than a stock VL 3.0..

I've used Apexi N1, HKS Hi Power, DRIFT, St Mays all on RBs, and the HKS Super Dragger has been the most quiet one.

when the core heats up, becomes an exhaust restriction, this easily can be done with a few squirts on throttle on full song.

Why would it only be a restriction when it's hot? The substrate doesn't change, it just gets hot...

Will also see some decent fines from the EPA if caught :)

Eh, we're in WA ;)

Yeah that's a good point. Easy to check too. I can fully understand not making as much as ex gate versions up top but should be close as I've got extensive head work and cams etc but I would think midrange should be near identical. But looking at boost I have 13psi at 3700 while Stao's latest was at 21 so no wonder it's 110hp lower.

Going to check actuator preload next day off and see if that's ok too. Try to double check VCT ASAP. Come to think of it I haven't heard the solenoid clicking like it used to. Vct obviously affects boost curve in a big way?

Vct is practically make or break for an RB25 on vct based cams.

if that's not working deduct something like 1000rpm for boost threshold. its silly.

Well it was done but cos I dropped the car off before Sean got there and we didn't chat he set boost to 18psi max and very safe. Only made 340hp but he told me to ignore the number as he can never reproduce Hp numbers that hypergear customers expect. So I drove home and gave it a couple squirts and it feels good. Maybe it was similar power but just low reading dyno...until I compared my result to previous results and it seems lazy on boost. Might need more preload. So thinking of taking it back after doing the exhaust and Sean said we can try put 21+ down its throat

Any other thoughts? Mine is red

Power

photo_zpsfe9a9fae.jpg

Boost

photo_zps4956dc8c.jpg

That's a little disappointing...

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