[Infern0]

Originally Posted by VAZL1

Something to consider! Where is everyone buying E85? I usually get my gas from Costco because it's Top Tier fuel but they don't carry E85 at least not where I live.

http://www.vacleancities.org/station...ation-locator/

Looks like Dale City, Manassas, Potomac Mills, Quantico near 22193.

[KyleL]

I planned on doing an intake first, followed by a cat delete, ported to/snout, then pullies/tune. I'm in the same boat as you with deciding on headers and from what I've seen, the power gains don't justify the cost and time to install. A cpr 2.31 upper and iw 9% reduction lower will spin the blower to 25k rpms at 6500, which is already 3k higher than recommended, but what a lot of c7z owners get away with. An 18% reduction puts blower rpm closer to 30k which means you'll be rebuilding it soon. All of this will run between $3-4K and put down somewhere in the 650-700 rwhp range and will drive like stock and be close to maxing out stock fueling without having to worry about running out of fuel.

Another one of my options is to do the intake, cat delete, ported tb/snout and nitrous. Cost would roughly be the same, power would be roughly the same and I'd drop iat's instead of just creating more hot, pressurized air. Downside to this is having to refill a bottle. I can get medical grade nitrous from a shop about 20-25 min away from me and it's reasonably priced, but it's a extra trip which consumes extra time and money. But I can also control when and where I use it too.

I have no intentions on meth injection bc I've seen people destroy their motors when the pump fails or they're careless and don't monitor their level, it seems like too much of a liability on a 70k car

Another point worth mentioning is your ultimate goals. Taking a look at the fast list, it seems as though the only blower cars outrunning a nitrous car are the ones with meth kits. Also, the fastest zl1 to date did it with nitrous. If pullies from c7z's will work on our cars, why not just go that route and try to bust 9's that way? Also, if I decide to do auto x and drag racing, all that power all the time may be too much for some tracks so you have the ability to run a bolt on setup for the twisties and a nitrous setup when you're chasing an et.

[STUNNAH]

Originally Posted by VAZL1

Would be interesting to see what those mods would gain. I'm with you on the catch can was waiting on that until I decided to pull the trigger on other mods and not void the warranty any sooner than I had too. Considering one without the clean side separator since the 17 model comes with one.
Do you think changing the X-pipe would be worthwhile?

The mods that were mentioned previously should net 70 to 80 rwhp gain the higher # with a manual tranny, money would not be wasted because you can continue to build on this platform...That's without any change to the exhaust system, X pipe would be of no benefit, pull the fuse to leave the cutouts open...

E85 conversion is a good option but the cost of the initial setup would be 3k -5k depending on the choice of injectors, flex fuel sensor, and fueling (BAP vs dual pumps)...I would never choose E85 as a 1st mod, 2nd stage mod at best...

[STUNNAH]

Originally Posted by KyleL

I planned on doing an intake first, followed by a cat delete, ported to/snout, then pullies/tune. I'm in the same boat as you with deciding on headers and from what I've seen, the power gains don't justify the cost and time to install. A cpr 2.31 upper and iw 9% reduction lower will spin the blower to 25k rpms at 6500, which is already 3k higher than recommended, but what a lot of c7z owners get away with. An 18% reduction puts blower rpm closer to 30k which means you'll be rebuilding it soon. All of this will run between $3-4K and put down somewhere in the 650-700 rwhp range and will drive like stock and be close to maxing out stock fueling without having to worry about running out of fuel.

Your build appears to be the opposite of what many of the members choose to go...If you go as planned you have not accounted for the additional fuel upgrade/injectors...Your pulley setup is to aggressive and will cause failure to the SC or motor, unless you cam it...Wasted money on porting the snout, without a porting of the heads...Upper pulley should be 2.5 with a lower of 8.6 which is 31% over driven and well within the safety margins...You may want to rethink your build...IJS...

[KyleL]

Originally Posted by STUNNAH

Your build appears to be the opposite of what many of the members choose to go...If you go as planned you have not accounted for the additional fuel upgrade/injectors...Your pulley setup is to aggressive and will cause failure to the SC or motor, unless you cam it...Wasted money on porting the snout, without a porting of the heads...Upper pulley should be 2.5 with a lower of 8.6 which is 31% over driven and well within the safety margins...You may want to rethink your build...IJS...

What is the potential power limit of the stock fuel system? This setup I mentioned should put the car between 650-700, which seems to be where I'm seeing people get to on stock fuel. This is the formula I used to calculate s/c rpm...crank pulley/sc pulley=x. X * engine rpm = sc rpm. So based on that, the 9% reduction (or 8.75) lower with a 2.31 upper, when divided, yields 3.787878. Multiplying that by 6500 rpm equates to a sc rpm of 24,621. This does overspin the blower, however, from what I've seen from c7z's, that seems to be an rpm that makes decent power without boost falling out on the higher end, which would be the case if you were to really overspin it, say closer to 30k rpms on top of almost guaranteed sc failure. I don't see the lt4 not being able to take a few extra lbs of boost and hurting the motor, unless it runs out of fuel or has a shitty tune. A cam will help ensure it won't run out of fuel but won't have any bearing on over revving a supercharger since that forumla I mentioned is based on engine rpm

There gains shown of 15-20rwhp from porting the snout. Do I think that is a waste of money? That's all opinions since intakes don't pick up a whole lot more and cost the same as the port work. Headers are picking up about the same but costs 3x as much. I think the 2.5/8.6 you mentioned are stock sizes to begin with.

Then there's always the stock pulley setup with a little spray on top too

[Can'tHave2MuchHP]

Originally Posted by STUNNAH

Your build appears to be the opposite of what many of the members choose to go...If you go as planned you have not accounted for the additional fuel upgrade/injectors...Your pulley setup is to aggressive and will cause failure to the SC or motor, unless you cam it...Wasted money on porting the snout, without a porting of the heads...Upper pulley should be 2.5 with a lower of 8.6 which is 31% over driven and well within the safety margins...You may want to rethink your build...IJS...

Originally Posted by STUNNAH

The mods that were mentioned previously should net 70 to 80 rwhp gain the higher # with a manual tranny, money would not be wasted because you can continue to build on this platform...That's without any change to the exhaust system, X pipe would be of no benefit, pull the fuse to leave the cutouts open...

E85 conversion is a good option but the cost of the initial setup would be 3k -5k depending on the choice of injectors, flex fuel sensor, and fueling (BAP vs dual pumps)...I would never choose E85 as a 1st mod, 2nd stage mod at best...

Hey do you realize you're on the 6th gen Forum lol? All that info is correct for the 5ths but not for the 6ths lol.

[VAZL1]

Originally Posted by psalmon123

Lingenfelter basically told me headers were a waste of money on the pulley tune mod.

Wow that interesting news!

[VAZL1]

Originally Posted by Infern0

http://www.vacleancities.org/station...ation-locator/

Looks like Dale City, Manassas, Potomac Mills, Quantico near 22193.

Awesome! Thanks...

[mlee]

Originally Posted by VAZL1

Something to consider! Where is everyone buying E85? I usually get my gas from Costco because it's Top Tier fuel but they don't carry E85 at least not where I live.

It's all over the place in Texas. No worries for me and with flex fuel you can go both ways.

Originally Posted by psalmon123

Lingenfelter basically told me headers were a waste of money on the pulley tune mod.

Exactly... If headers don't provide large HP gains then you're losing the boost you just added with pulleys by adding headers.

[bybcous]

Where are you in VA? There are e85 stations not listed on that website earlier in Hampton roads and several other areas.

[hawk02]

Originally Posted by mlee

Exactly... If headers don't provide large HP gains then you're losing the boost you just added with pulleys by adding headers.

Yes, but isn't the theory that even though you lose boost with headers you're still gaining power because the engine is "breathing" more efficiently?

[Can'tHave2MuchHP]

Originally Posted by mlee

Exactly... If headers don't provide large HP gains then you're losing the boost you just added with pulleys by adding headers.

The boost is still there, same HP, but the PRESSURE is lower.

Originally Posted by hawk02

Yes, but isn't the theory that even though you lose boost with headers you're still gaining power because the engine is "breathing" more efficiently?

[VAZL1]

Originally Posted by Can'tHave2MuchHP

The boost is still there, same HP, but the PRESSURE is lower.

Agreed, less pressure more volume!

[utsteve98]

Considering these engines are putting out 650 I imagine GM designed the exhaust system well. With a SC not sure how much gain you will get from headers given the higher pressure of the exhaust already forcing itself out.