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Hi guys i was wondering what and how whould an engine behave if the turbo housing is to small. Not using a dyno just pushing it hard. Im thinking the housing is a bit small on my gtr, but im a bit mixed up because the car runs so good. Any clues would be appreciated.

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If you guys listen to the motor can you be able to tell from the sound of it. Sorry question sounds dumb. But all the other stuff seem ok. Im at around 1000f on the EGT gauge when im in the gas. What im hearing is like at top rpms when doing a durn out or lauch the rpms seems to get like a scramble sound. Dont get me wrong when i dump the clutch the car goes. I had a friend do a burn out for me so i could record the sound. Cant you by any chance tell what it might be from the sound of the exhaust. ??

Well i cant tell torque drop off no dyno:( timing im not to sure about.

I can say its all cheap stuff.

Cheap ebay 38mm gate $69

Cheap ebay manifold. $159

Cheap hx35 diesel turbo. $370

Stock injectors

Wolbro 450 pump intank $ 110

Power fc. $800

Twin rb25 afm. $180

The motor is stock rods and pistons

Just rebuilt fresh with arp head studs acl bearing, MLS head gasket. Its also has a racefab sump.

And a fully refurbished head.

Its really a budget build.

Juat wish i could figure this out

Edited by MJTru

Well its not detonation. The power fc is at 42 knock max at 14psi. Thats ok to me. My work tends to be tidy with nothing hitting the block (false knock) well untill i get a dyno i guess ill have to stay guessing. Or using my god given talents. I know about the torque drop off part just have no way to figure it out.

Makes me want to move somtimes. So much guys blow up motors here due to tuning issues. Even i did. Untill i first learned my limits and some road tricks to follow, by no means is it a method that is better over using a dyno.

I stop spending big money on parts and turbos. I use cheap ebay and Chinese crap to build, well other than the motor part. I keep it stock just fresh and push the oil issues to the limit. This whole build was under 2k.

The performance is ok. But well worth the money. The only think i have going for me is i can build my own motors. Thats it.

Thanks anyways guys. For everything

Standard injectors are only good for around 400hp to the tyres so if you're making any more than that they're probably at their limit.

What times and mph are you running?

Standard GTR or GTST injectors? Also - dirty injectors may only flow 2/3rds of clean injectors...

You guys might just be right. The injectors are maxing out. And fast. There rb26 injectors. I do want to buy a set of injectors but to tell you the truth. I dont have a dyno so only injectors that come with the lag times would be the set im interested in. Like the stuff on rhd japan. Once i do the formula and input it into the power fc. Its just a matter of clean up the fuel map a bit. Thats all i can do lean some mistakes maybe even blow this motor up and start over again. People say the those injectors are old fashion and i should go with some newer stuff like mega squirt or somthing like that. Does any of.you guys know what would be a good option in this situation. I really wouldnt mind a set of upgraded injectors.

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