Poppa G

Hi guys I have a some questions for the few of you who have added a large supercharger to your motors.
I have a 2002 c5 corvette with stock (rebuilt) LS1 short block with
Dart pro 1 heads
Fast 102 intake
comp cams .617/624 lift at 113ls
ls2 t/b
DeWitts radiator
C6 zo6 exhaust system w/ borla straight pipes
RPM tranny and Diff w/3.73 gears
I'm a newby to hp tuners pro.
I recently added a V7 YSI A&A kit with required fueling upgrades. I am looking to have a start up tune done and spoke with Doug at ECS for that. I was planning on running it this way till winter then building a 427 forged boost motor.
My questions are how much boost should be acceptable for this setup?
Does any body have hp tuners that I could get a copy file from to analyze (with similar setup)
I have a 3.8 pulley on it right now to keep boost low till new motor, what do you think?
MAF or Speed Density tuning ?

Any input, feedback or suggestions would be appreciated.. Thanks guys

Turpid porpoise

Check out the HPTuners repository for tune files that are similar to what you will need.

I wouldn't recommend driving around on just a start up tune without getting it dyno or street tuned to clean up any potential issues that can't be predicted.

Most stock LS1's seem to stay fairly happy around the 550-600whp level and they seem to come apart more frequently above 600WHP. Rings and rod bolts tend to be the culprits. Can't tell you what boost level will generate that power but I have heard from a number of reputable guys that 10 psi is the most you should run on stock rings.

I've been running SD for 2+ years now on the street with no issues and no more MAF to deal with so I'd recommend that as well.

ysb02

I'd run a 4" pulley and speed density.

stevieturbo

You dont mention what compression ratio, you dont mention what fuel.

Two of the most important factors.

BLOWNBLUEZ06

Since Doug is tuning it, you should consult with him on what he's comfortable with. I would guess his answer will be around 10-12psi although, like me, he's run 20+ on cars with stock bottom ends that have lasted for years without issue. That's on pump gas and meth. It takes a certain customer to run big boost on a stock motor.

Millenium Z06

Wayyy too much gear to. 3:73's are going to keep you at the upper end of the rpm range anytime you're on it (spinning) further stressing the rod bolts and ringlands

SBCGENII

The less time the engine spends at lower RPM and high torque the easier it is on the rods. I rember some some 97-98 motors having rod bolt issue way back in the day. Could have just been a bad batch. You will bend a stock rod before the bolts break.

C5Natie

You'll need to go with a big pulley to keep boost low since a stock bottom end can't handle what that Ysi is capable of. More than likely it'll feel lazy since those blowers like to be spun hard.
I have a Ysi putting out 25psi into a forged 5.3L

Millenium Z06

We're talking rod bolts and ringlands, not rods.

Poppa G

Compression is (unfortunately) 11:1 it made over 400hp at the tires NA.
Here in ohio we have access to 93 all day and even race gas at some places.
I will add meth sooner than later.

Poppa G

I was goona keep it NA for awhile, but when I came across this ysi kit I had to buy it.
When I bulld the 427 cube or bigger it will handle those gears... I will need alot more tire though!!

Millenium Z06

No it wont, you wont stay in your power band long enough to utilize the power, you rev and spin then run out of motor and gear. A boosted 427 will make a lot of power and a lot of torque, that doesn't require a lot of gear. Look at most of the big power guys 700+ whp, they are 3:42 or higher (numerically lower). Unless you're planning on running the 1/8th and have the drive train for the tire, you'll run out of gear and be north of 7k rpm

ysb02

it seems that the c6 z06/zr1 rearends only have the option of 3.42 from what I've found. That's probably why it's such a common ratio to see.

Millenium Z06

Its a good all around gear for fuel economy vs performance. Big power (and torque) doesn't need a lot of gear; gear is a crutch for low power. Thats another reason why the C5Z guys that make power get rid of the MN12 and go to the M6 or the 6060, better gearing

ysb02

I agree on it being a good jack-of-trade gearing but I've seen guys use 3.90s with ZR1 ratios on the road course, 4.10s for drag racing, 3.15s for mile, etc. It really depends on what you're going to use the car for and if you want to specialize in certain areas.

I'm ready to sell off my MN12 and install the MN6 gearing of the t6060 I picked up. 12 is fine for N/A road course work but MN6 is much better for centri setups.

Millenium Z06

Ytue. I'm looking for a 6060 swap too, I'd like to stay in 2nd and 3rd a little longer