well so far I've turned it up to about 12psi from 8 and it feels GREAT!!! this motor is finally starting to feel like its supposed to

The only problem I'm having is somewhere between 10-12psi, is as far as I can adjust it accurately. last night on the way home in nice cold air (~46deg) I dropped it into 3rd, and stabbed the throttle. Downshifted to 2nd and noticed the speedo was gaining MUCH faster than the truck... and it definitely felt like the ***-end was wanting to go the other way. Am I experiencing tire spin at 80+ mph? I guess if I am, I can attribute it to the truck being lightened so much. It goes from about 80-100+ as fast as you can take your eyes off the road and look at the speedo.

I'm shooting to end up about 15psi. I'm thinking now, the last of the boost controller tweaking will end up happening at the track with traction and I'll turn it back down to run off the wastegate on the street on 8psi, anything more than that is pretty much pointless...

 

glad you go it workin lol. I didnt have that email saved...

 

When I first started making power, I started learning about moist areas on roads on cool nights, how slippery dry road salt is, how polished asphalt is, and the only safe place is a brand new, 4 lane, concrete highway with rain grooves.
Oh, yeah, and I learned how a puddle that appears out of nowhere at night on an otherwise dry road can really upset your handling when the gas pedal is mashed to the floor.

 

What kind of controller you using

 

manual turbosmart controller... took a while of adjusting and making test runs before it actually started engaging and working with the wastegate properly. This thing is touchy as hell to adjust LOL.

 

are you tunned for high boost

 

no I plan to run it on the same tune....












- j/k, I do my own tuning. I havent changed the fueling yet and its still good to go, on 8psi I was in the mid 10's AFR, and upping the boost has put me in the low 11's so its still good. I've just turned the timing down a hair. I keep a close eye on the wideband. I dont plan on going over 11.4ish with the AFR... probably around 18-20deg timing. 15psi, isnt exactly high boost yet either

 

Glad to hear you've finally got this thing running like you had hoped. Blowing off the tires at 80 is downright sick.

BTW, could you remind me exactly which Precision turbo you run?


Michael

 

the GT78H with .96 hot side, T4 flanged. I'd really like to step up to a T6 setup and more cubes, for EGT sake, but this one is doing the job for me as of right now. It does feel good to have this motor coming into its "comfort zone" finally. At 8psi, it makes power but you can tell the thing is holding back reigns so to speak. Finally letting it run is feeling good... the trans feels more comfortable with the more power I throw at it too. too jerky on low boost. IMO.

and FWIW, it did this on a fresh concrete 4 lane right outside town

 

What sort of T6 are thinking of stepping up to? What would you consider a good turbo in between a turbonetics T78/Precision T78 and something like a PT/GT88? I've been doing tons of reading and it seems like there is such a fine line in regards quick spool for response on the streets and then power up top at the strip. Also based on my reading I'm really liking your choice of 347 cubes. Less backpressure issues than say a 370, but you can still turn the wick way up and make 800+ to the tires. And you will maintain superior gas mileage to a 370. But I suppose there are worries (mine) about 347 cubes being enough to lug around a heavy truck....compromise I suppose.