Got the parts ordered! 
Dyno, need opinions please.
Staging Lane
Joined: Aug 2010
Posts: 82
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From: Louisville, Ky
Pretty sure they're sponsor's here. Fwiw, I just googled the springs and they were the first to come up. I have no dogs in this race.....
http://www.lmperformance.com/5031/1.html
http://www.lmperformance.com/5031/1.html
Teching In
Joined: Jan 2011
Posts: 1
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Turbo cars are alot harder on valve springs then supercharged cars. I have a ls1 c5 with 140,xxx HARD HARD miles that is on 14 psi and is running fine on the stock springs and pushrods. I would do something with the cats and try springs if you dont find anything else.
A little word of advice, next time you work on someones car don't claim that you own it cause you worked on it. I house sit for my sister all of the time. I don't claim that i own her house.
Dont pretend to be something you're not. Just be who you are. Thats what's really cool.
Exactly the opposite of what I would do, because the risk of hurting the engine from weak valve springs is much greater than the cats hurting it. Plus, it seems pretty unlikely that power would drop at exactly the same rpm on every single pull if it was a converter issue. It would vary based on how hot the cats were on a given pull. At least from my experience that's the case.
But that's the great thing about opinions.....
But that's the great thing about opinions.....
For what it's worth, I've had very few problems with centrifical superchargers and worn out valvesprings. The cats would be the first place I would look too as back at the old shop we often found clogged cats on forced induction cars. You'd be surprised at how often we'd have cars spitting out pieces of their cats right on the dyno. Bob
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Staging Lane
Joined: Aug 2010
Posts: 82
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From: Louisville, Ky
Originally Posted by Bob@BruteSpeed
You'd be surprised at how often we'd have cars spitting out pieces of their cats right on the dyno.
Actually Bob, I wouldn't be surprised. I've been seeing the exact same thing for over 10 years now, which is why I said I never like to use cats on boosted cars unless they are required (emissions issues, etc.). But in trying to diagnose his specific problem, I don't believe it's being caused by the cats. Simply because of the drop in power at the exact same rpm every pull. But I could certainly be wrong.
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Staging Lane
Joined: Aug 2010
Posts: 82
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From: Louisville, Ky
That seems to be more the case with NA engines in my experience. Boosted cars usually look more like a "drop" in power on the graph. My guess is that it has to do with the fact that most boosted cars pull through rpm's faster, leaving less dyno sampling time for it to look choppy. But again, these are all just my opinions.
Staging Lane
Joined: Aug 2010
Posts: 82
Likes: 0
From: Louisville, Ky
Here's a thread from nearly 3 years ago in which I posted that valve springs were the problem with the car. He's turbo'd with ls6 springs and his power also just drops off on his dyno graphs. He was super reluctant to replace them and spent nearly two months trying everything else. Patriot Gold's took care of it. Just sayin'.
https://ls1tech.com/forums/forced-in...-diagnose.html
https://ls1tech.com/forums/forced-in...-diagnose.html
8 Sec Tuner
iTrader: (2)
Joined: Jan 2002
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From: Wish I was in a boat fishing...
Trust me its valve float! Ls3 valves are heavy. Car pulled fine until you added more boost.
Also pushing lots of fuel through stock manifolds and cats on a boosted car is asking for problems.
Also pushing lots of fuel through stock manifolds and cats on a boosted car is asking for problems.
8 Sec Tuner
iTrader: (2)
Joined: Jan 2002
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From: Wish I was in a boat fishing...
Trust me its valve float! Ls3 valves are heavy. Car pulled fine until you added more boost.
Also pushing lots of fuel through stock manifolds and cats on a boosted car is asking for problems.
Also pushing lots of fuel through stock manifolds and cats on a boosted car is asking for problems.
Staging Lane
Joined: Aug 2010
Posts: 82
Likes: 0
From: Louisville, Ky
Teching In
Joined: May 2009
Posts: 1
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The same yellow car that has self made valve reliefs on 2 cylinders?
A little word of advice, next time you work on someones car don't claim that you own it cause you worked on it. I house sit for my sister all of the time. I don't claim that i own her house.
Dont pretend to be something you're not. Just be who you are. Thats what's really cool.
A little word of advice, next time you work on someones car don't claim that you own it cause you worked on it. I house sit for my sister all of the time. I don't claim that i own her house.
Dont pretend to be something you're not. Just be who you are. Thats what's really cool.
My numbers 5 and 7 intake valves crashed over three years ago because of a 4-3 UP-SHIFT! Shortly after that I changed to LS6 springs and replaced the two mangled push-rods for those same two valves. And even when I did that Anthony warned me that those springs just weren't enough, not just because it's supercharged, but because I drive it on the limiter all the time. Now it's become even worse, not only do I continue to over rev the **** out of it, He's got it making so much more power the LS6 springs don't have a chance. But that will change soon, Anthony just bought me a new set of springs, in fact he's given me a lot of parts for my car. So if he refers to it as his, I can understand why. Even though he's never once driven the car, not even on his dyno.
Your one and only post was to call out a shop owner because he said "I've got a C5"? I called Napa and said "I've got a 2000 Ranger and I need a set of brake pads for it"...I really don't own a 2000 Ranger, it's my Dads truck, so shame on me for pretending it's mine.
Thread Starter
On The Tree
Joined: Jul 2009
Posts: 182
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From: Houston
Got in one pass tonight, clutch only had 250-300 miles on it. Spent all night on Thursday trying to break it in for the dyno above tonight. Headed out to the track, only got in 1 pass and they said no more. Baby launch.
http://www.youtube.com/watch?v=hkpqz3T6ltc
Probably could have got it down to a 10.3 or 10.4, but the officials said no more. I'll be running at HMP to get used to the car since this was my first time to launch it. Then I'll add some more power and see how deep in the 10's I can go on the stock block.
Thanks to everybody that posted in here!
Good deal, I'm glad you got it figured out! You'll drop a lot of time off that already great 1/4 time just be getting more time in behind the wheel at the track. Bob
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ATI ProCharger and Moser Sales 260 672-2076
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E-mail: brutespeed@gmail.comob@brutespeed.com
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ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
Thread Starter
On The Tree
Joined: Jul 2009
Posts: 182
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From: Houston
BTW, love the ACT twin clutch. Affordable, feels great on the street, and felt fine tonight.
Mark
Last edited by winters97gt; Jan 22, 2011 at 04:43 AM.
No problem Mark.
One more thing, looks like you could also pick up some power and torque down low with a little more tuning. The A/F looks GREAT as far as being straight as an arrow, but on a cent blower setup, it's better to be a little leaner down low and then ramp up the fuel along with the increase in boost throughout the rpm. If you look at your graph, you'll see that right around 2800, it starts getting richer, and at the same exact time the HP and TQ both drop right along with it. Then at 3500 when it leans out just a tiny bit, the HP and TQ both climb right along with it.
BTW, I'm not knocking the tune at all, just offering up a suggestion that might help out a bit.
One more thing, looks like you could also pick up some power and torque down low with a little more tuning. The A/F looks GREAT as far as being straight as an arrow, but on a cent blower setup, it's better to be a little leaner down low and then ramp up the fuel along with the increase in boost throughout the rpm. If you look at your graph, you'll see that right around 2800, it starts getting richer, and at the same exact time the HP and TQ both drop right along with it. Then at 3500 when it leans out just a tiny bit, the HP and TQ both climb right along with it.
BTW, I'm not knocking the tune at all, just offering up a suggestion that might help out a bit.
That thing is running hard! A 7.0 with a 108mph trap in the 1/8th, you're missing quite a bit in the launch. Once that thing gets going though, it rolls out!
I'm sure you'll be surprised when you put headers, cam, and valve springs on it!
I'm sure you'll be surprised when you put headers, cam, and valve springs on it!