Ryans99ls1

iTrader: (16)

Put this up in the dyno section too, figured you guys might enjoy it more.

Swapped my turbo out from a TC78 to a Precision 7675 GTS-H. The bigger turbine let the car hold boost better and it made 690 right off the street.. no changes whatsoever. threw another degree in it through the entire range and fattened it up to 11.0AFR throughout (was 11.4-5 through the first pull). Tuner said my 80lbs were maxed on this pull but it was pretty cool to see.

Timing at peak torque is 14deg, at peak hp its 19-20deg.
Boost was at 16psi and fell to 15psi by the end of the pull.
IATs went from 67* to 98* by the end of the pull (4" thick ebay intercooler)
Left the dyno at 12lbs so its back down to 680-690. I still may bring it down some more cus the rods are going to be extremely angry with me, all depends how i gear the car.





Side note: when it made 630 last year, the car had stock heads(853s), stock head gaskets and stock head bolts.
Link to last years results: https://ls1tech.com/forums/dynamomet...hp-inside.html

This year: stock untouched 317s, ls9 gaskets, and ARP head studs. NO other changes, at all (besides turbo).

So realistically, i picked up 60rwhp by switching to the PT7675 and putting on the 317s, not bad.

Ill get a video this weekend when i go back for the dyno day, we had to sit on the rear to keep if from spinning so i couldnt get one.

Nismo Kid

iTrader: (3)

Nice numbers man. How many miles do you have on the stock bottom end? No matter the mileage its impressive.

Ryans99ls1

iTrader: (16)

Thank you. 50k on the bottom end. Also put in BR7EFs and switched the oil to Rotella T6.

Just for justification, at ~600 last year, the car ran dead even with a proven 133mph car. So the power/trap speeds are on for a 3600lb car

itsslow98

iTrader: (18)

If you pick up an eboost street boost controller for like $250, you can correct that boost drop off in the upper rpms and make it hold the boost rock steady. Damn impressive numbers for the mods.

Ryans99ls1

iTrader: (16)

Thanks! But yeah Ive been meaning to buy an eboost street but have literally not had the time to buy/install it. Ive got a 2step/wot box i need to install as well.. along with a clutch and new rear gears lol

With the TC78, no matter what i did it would spike to where i wanted it (12lbs) and then fall back to wastgate(9.5lbs) by redline. I put the the PT76 on, didnt touch the **** from last year and it held it to 11lbs. The backpressure was the biggest issue. Ill get an electronic controller on it this year.

LT1RAY

iTrader: (21)

Awesome results, I hope my T7875 performs the same.

Burken01

iTrader: (88)

dang!!! this build is very similar to mine...

this thread makes me wanna hurry the f up and finish my car

very nice, I bet its a blast to drive

itsslow98

iTrader: (18)

Yea for the money I love mine. I had the same issue with my manual BC dropping off up top. I wired up the eboost street and never touched the rpm correction and it hit my target boost perfect and held it perfectly all the way to redline. At half the price of the eboost 2 its often overlooked for some reason.

Ryans99ls1

iTrader: (16)

No reason it shouldnt! things really started taking off past 12lbs.. it was wild. Amazing what a turbo in its efficiency range can do huh? haha

Oh that it is. The m/t's hold perfect in 3rd and 4th. 2nd too if let it spin a couple times. glad i could serve as some motivation!

i like the big digital readout too. much easier to see if things are where you want them to be.

Burken01

iTrader: (88)

because its big and where can you mount it, do you have pics of how you have it in your car? and what can the 2 do better than the reg eboost?

OP you sould do video soon of your car, I need motivation

Ryans99ls1

iTrader: (16)

the street and 2 use the same solenoids to regulate (from what i remember) the eboost2 can just get a lil more in depth in regulating boost. If all you want is rock solid boost and a couple different boost settings, the street is the way to go.

heres vid from when it was around 600 with the TC78. i need to borrow my buddies go pro, gimme a week and i should have a few. Graduation and what not is taking over this week for me.

Burken01

iTrader: (88)

looks solid! I hope to make similar numbers

My engine guy has had my shortblock for almost 6 weeks, Im ready to put the car together I havent driven it since Oct 2011

Ryans99ls1

iTrader: (16)

Numbers are great but last year i told him i wanted a 130mph car, he gave me that. Its got atleast 7-8mph more in it now so im happy. Your combo should be very stout judging by your sig.

itsslow98

iTrader: (18)

I put mine in my glove box because there really isnt a need to have it in sight when you have a boost gauge already. The 2 can do boost by gear and I think more then 2 boost settings. Other then that they use the same solenoid. I dont need boost by gear so that is a useless feature IMO. I also only have a high boost tune and low boost tune.

Burken01

iTrader: (88)

hmm good idea, Ill look into that.. 2 settings is all Id really need come to think of it (fast, faster) lol

Burken01

iTrader: (88)

Yeah I'm building my for the track and some grudge dig racing...

I didnt plan on going overkill parts on this 347 ci engine when everyone is doing 6.0's and lsx engines... but I wanted something I could beat on for a good year or so and not have it break for any reason.. then I can sell it to help fund my future build, plus I can reuse half the stuff on my next build..

dang 138? if you can hit that good for you bro...

Jetn3

What does your exhaust consist of and what size after the pt7675?

a4ls2goat

Great numbers.

I will be dynoing my 7675 billet wheel on a 4.8 tomorrow. Looking forward to the results.

racegirl7111

Holy crap, that's impressive. Congrats on the numbers

02sleeperz28

iTrader: (26)

Very nice numbers! Maxing out the 80 lbs, wow! What was your duty cycle at that power level? What fuel system do you have?

Does anybody know what power level the pt7675 can handle comfortably without maxing it out? 800, 850rwhp?