need advice on a downpipe

[toomanymodz]

yeah ss thdp's are **** i will buy yours for $100 if it is ss ?

I already sold the THDP. Sorry.

 

[toomanymodz]

Compare this with post #14. The WG hole is much larger now.


Primed the engine, then installed cam sensor. Engine is ready to be installed.

 

[Warp6]

Do you have good control of boost with the new downpipe?

 

[~JM~]

Please excuse my ignorance, but what does enlarging the WG hole accomplish?

Thank you
~JM~

 

[jasjamz]

Please excuse my ignorance, but what does enlarging the WG hole accomplish?

Thank you
~JM~

Helps control boost creep and has an effect on how low you can get boost levels. If he did not port it, boost would be 29-30 minimum. I had that issue. Bolted my 6765 on and hooked the internal gate up with barely any tension and saw 30+. Ported the hole some and got it down to 22-23psi worked my way up from there. Still had 2-3 psi of creep that I could of fixed but sold the turbo.

 

[rmar]

What he said......

John.
It allows you to control the boost on these new fangled turbos a little more precisely....With a internally gated downpipe.
Otherwise you can't hardly get them to 20/23 psi.

 

[northerngn]

Please excuse my ignorance, but what does enlarging the WG hole accomplish?

Thank you
~JM~

It allows you to lower the boost on the turbo...these new ones are crazy on how efficient they are...
I recently picked up a 67/65 with a 4 inch inlet and a .85 (the larger option) exhaust housing through Hartline Performance...
Even with the engine just being a 233, having the larger exhaust housing on the turbo, and having the d/p be a 3.5 in, with the wastegate rod having little to no preload on the puck arm this new little turbo wanted to run 25+psi...and i mean RIGHT NOW...
It was only after conversing with Cal (Hartline) I was referred to RJC and informed of the bigger puck...
After installing the puck and opening up the hole as well as blending it on the inside of the turbo i can run wide open with the boost as low as 18psi now...

Sorry the explanation is a little long but, I'm sure your onboard with why its needed now:smile:

-Dan

 

[~JM~]

Great explanation guys. I understand now. Thanks.

~JM~

 

[oldsracer]

View attachment 148713

Just thought id say it since no one else did...BEAUTIFUL MOTOR:biggrin:

 

[jasjamz]

Just thought id say it since no one else did...BEAUTIFUL MOTOR:biggrin:

He has another thread that shows the engine and install where he has receieved a ton of comments along the way. This one was more downpipe oriented and I just can't bring myself to compliement another guys downpipe...LOL:biggrin: Im sure he understands.

 

[toomanymodz]

Thanks guys. Just to follow-up on the ported WG hole. It works wonderfully. When I first started the engine, I set the WG rod extended, and I had just a plain rubber line running from the turbo to the actuator. I wanted to see what the lowest possible boost was. The result was about 11 psi of steady boost, no creep. So porting the WG hole like I did definitely will allow total boost control as low as you want it.

 

[Warp6]

Thanks guys. Just to follow-up on the ported WG hole. It works wonderfully. When I first started the engine, I set the WG rod extended, and I had just a plain rubber line running from the turbo to the actuator. I wanted to see what the lowest possible boost was. The result was about 11 psi of steady boost, no creep. So porting the WG hole like I did definitely will allow total boost control as low as you want it.

Have you run high boost yet with the ported hole? Curious if it will still hold solid at 25psi. Thanks for the update.

 

[toomanymodz]

Have you run high boost yet with the ported hole? Curious if it will still hold solid at 25psi. Thanks for the update.

Not yet. I'm working through an issue with some oil mysteriously accumulating on the back of the engine. Gonna change valve cover breathers to see if it helps.