my ls turbo is losing boost at 5000 rpm
t3-t4 turbo with replica blow off valve and a replica external wastegate
all stock internal stock injectors pretty much stock b16 tranny getting a ls soon
it was boostin good before i took out the wastegate and added the ring that sits between the manifold and the wastegate. not sure if i install the ring right.
turbo boost good until it hits 5000 rpm then it feels like i have a rev limiter



thank guys
leave yo negative comments to yourself

 

get rid of the replica stuff. get engine management and bigger injectors first. And stop boosting until it gets tuned. a ring between the manifold and wastegate?

 

Prolly a thread that would be better answered in the FI forum, but...

I would guess a leak near the wastegate, or the wastegate itself...esp since you just worked on that part of your system.

"Replica" parts, moreso for those that have moving parts, are known to have horrible quality (leak). I'll see if I can find the thread that shows the difference.

 

He probably means a gasket.
at least hes not building a Z6 =P

 

i like my 12 second z6.

 

What spark plugs are you running? It sounds like spark blow-out

 

im running stock ngk spark plugs
i got 550 rc injectors but no install
and for the ring its suppose to seal the air blowing through the other side of the wastegate
before i have the ring on it was blowing at idle and now its not but after 5000 rpm feel like theres a rev limiter

 

There's your problem. If you're tuned, then swap in a set of NGK BKR7e spark plugs. They come at a factory gap ~.30. Just double check that and toss them in...problem solved

 

can i just gap the spark plug

 

ok so wat do u guys think about me getting a fmu, fuel pump, get the rc injectors in, and a chip ecu and get it tune.
what kind of hp am i gonna get with this, what should i be axpecting at 7psi

 

tune it

 

not much at 7 pounds but definaly get it tuned with a fuel pump and injectors its prob starving for fuel.

 

no. You have to get a colder plug...its not all about the gap. If you can't afford the $7 for a set of plugs, you may as well sell it now.

FMU - f**k no. Get something else
Walbro 255 - yes
RC Injectors - sure...size them correctly
Chipped ECU and tune - now you're on the right track

As for the power you hope to make...none of us can tell you that because of your vague turbo description. I would be less concerned with the 7psi thing (since PSI doesn't mean or determine anything) and just keep your goals under 300whp on the stock block

 

A set of Stock DSM injectors should do it for the amount of boost your running. DSM injectors should be easy to come by

 

I take it you already have the RC injectors?
If you don't have them yet, I'd just get Precision injectors from Phearable.net. They're less expensive than RC injectors and work just fine.

 

thank guys but i already have 550 rc injectors and planning to get a fuel pump and a p28 and chip it. im guessing its not boosting at 5000 rpm because im not getting enough fuel in the system so imma do this and get it tune and well see what happens
thanks for all the comments. one last thing should i get this part call the missing link if im gonna chip a p28

 

Well if you weren't getting enough fuel your engine would lean out and after too much of that it would blow or whatever.
Go get your tune, your tuner will be able to figure out what's wrong.