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Since this post I've found a number of people boosting the LS7, from stock to forged, that have no problems and have been doing it a couple years or so. Some are boosting the stock engine as high as 10 PSI with no issues. I found one guy that says he regularly runs 15 PSI on his forged block and has had it as high as 18 PSI(though he did that only temporarily, because he had to run higher than 93 octane to WOT it).

Some people, not necessarily engines, don't need to run boost.
In battle, even in a devastating loss, some folks survive. That doesn't mean it wasn't a loss.

Point being, because a few have run higher boost on an LS7 and haven't blown their engines (yet) doesn't necessarily make it a safe and practical method.

Just curious, of those people you discovered running high boost, how many of them had gone the route you are planning (stroke the engine to 441) and then boost? How many of them run WOT often on the street or strip?

Don't get me wrong, I really hope your build works out for you and you have many happy years of driving but I still don't think it's the best plan of attack for the engine (but maybe I'm just one of those people you mention at the end of your post). :crazy:


As for tuning, I couldn't agree more of its importance, especially in boosted engines, but great tuning can't always make an unsafe situation safe.

Mike
 

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Procharger stopped selling there blower to a and a because od conflict of interest since they sell a kit. Vortech is apparently right down the street from them.
 

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zmy my this thread is wearing my fingers, im going to try and post simple replys now lol :lol:

racingvette:

Yes i spin very fast, to the red line :lol:

Did you expect me to explain every single detail of the setup on my first post? Every little detail?

I gave a general idea:

LS7 + E85 + Vortech supercharger will make around 650-700whp safely.

Do you expect me to explain everything all at once? Get everysingle detail in one post.

I stand by my original point that LS7 can make 650-700whp safely, in a "stock" form. Obviously some things will need to be modified. What did you think i said to keep every single thing stock about the car, keep original exhaust? keep original intake filter? Keep everything stock and just add a supercharger? And if i upgraded the injectors on the engine that will count as something that i failed to mention, and im adding things to the setup?

Obviously some things on the engine will be modified, but i still consider the engine stock in my opinion. Yes maybe i should of added this in my original post, but what am i gona sit there and worry about somebody every single little thing that i didnt mention and that somebody might poke at me for that little thing.


To me the engine is stock, if youre just adding easy "external" boltons, kind of like adding an intake, an engine with an intake is stock in my opinion.

So if you want the details what needs to be done to this engine then i will cover as much as possible, but dont poke at me if i left some little thing out, because its "implied"

Heres the setups:

Factory LS7 with:
-FAST intake manifold
-Upgraded injectors
-Knife edged throttle body
-Streetable long duration cam with factory spec lift
-Big fuel pump
-Full exhaust
-and maybe some other little thing i forgot, but the heads will not be removed, oil pan will not be removed. thus internally motor is stock.

if you say the engine overheats from boost, add a thicker aftermarket radiator, also the E85 will help the engine run slightly cooler during the combustion procces, im not saying it will lower the engine temparture because the thermost controls that, but e85 might help the engine not overheat. again things like this were implied in my original posting, i wasent gona list every single thing. just the general principle of the setup.

In my post #10, i posted to start at 5psi and slowly go up in boost untill you reach 650-700whp, you will probably need much less then 8-9 psi to make the HP, but even if you need the 8-9, E85 is a very safe fuel, and even at that boost will not detonate, and will run cooler which is a nice safety feature.

And you say supercharger companies recomend 4-5 psi with thier superchargers. That number seems like its right, but those companies assume you will be running 91/93 octane, and possibly meth injection. If they knew you ran E85 they would warranty a higher psi number. Also depending on what kind of supercharger you run, for a roots type supercharger it will be harder to make 5 psi then on a centrifugal type supercharger. If its harder for the supercharger too build boost therefore there will be more strain on the engine.


Intercoolers: Yes the bigger intercooler you can fit in there the better! im not saying to block off your engine radiator with the air-to-air intercooler, but run as big of intercooler thats possible without negative side effects. and its a air-to-water intercooler then place it properly, not just shove it on top of the engine. make things work right.

Not many cars run at sealevel? Please somebody give me a beer lol. Obviosly, the supercharger setup will make less power on a higher elevation, but dynos are corrected for altitude and humidity ect ect. My point is the car will make 650-700whp on a dyno, dynos use correction factors to tune for the atmosphere conditions. Or are you trying to prove that the car will not actually make 650-700whp at an elevation of 10,000 feet? hahaha thats true for any car it will make less power, why are you trying to poke holes at my setup :p :eek:wnd:


Yesss everybody knows a LS9 engine is better then the LS7, why are you even bringing it up hahaha. oh and the intergrated LS9 air-to-water intercooler bar in the supercharger is not placed in the best place, on top of engine it heatsoaks. but it was placed there because of packaging reasons and a more simple compact setup....

bloated dyno queen numers? if the enine make 700 hp then it makes 700 hp, theres no bloating about it. that 717whp thru an automatic ls6 that i talked earlier about? it ran [email protected] in the quater mile. and his engine ran with this insane amount of boost making aroung 950 hp at the crank for two years i believe, sure he might of went a little far with the 950hp on stock motor, but it proves lower hp can be run for a very long time.

doesnt matter how much boost your running even if you run 3psi, when the chevy dealer sees that you have a boosted engine they might not honor the warranty either way


8-12psi? where the heck did you get 12 psi from. i said start at 5psi and go until you reach 650-700whp, or 8-9 psi, which ever comes first.

calibiration tables, air to fuel maps, ignition timing, its all in the software, it not hardware haha:lol: and were not talking about ecu's here

E85 is unsafe for todays engines? i ran mine on a old ass 1994 engine. i live in a country that hypes that stuff? im in colorado you... :rofl:
ive used both pump gas and E85 ethanol in the past, and ethanol is superior in almost everyway performance wise.
you know nothing about E85 performance, and you dont want too listen.

yes E85 will reduce greatly the chance of cracking, due to detonation, also lower combustion temp help, cooler metal is less prone too crack.

so if you really hate the idea of e85 and dont beieve me about its amazing properties, then just stay out of this conversation :moon:

if you live in an area with speeds like 50mph, then why are you even on this supercharging topic, you obviously dont need boost, what are you doing here


posterchild of boost? booms and bangs? this is what this is all about WITH E85 THERE WILL BE MUCH LESS BOOMS AND BANGS, ITS LIKE RUNNING 107 RACEFUEL ALL THE TIME. which you dont seem too realize.



IF YOURE GOING TO LISTEN TOO ANYTHING AT ALL, REMEMBER THIS, WITH BOOSTED APPLICATIONS RUNNING E85, THEY WILL ALWAYS BE MORE RELIABLE. THEN PEOPLE RUNNING GASOLINE, OR EVEN RACE FUEL WITH AN OCTANE OF UP TOO 107. E85 WILL MAKE POWER MORE SAFELY
Truth is starting come out ..E85 performance, .
 

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I put an Edlebrock E-Force Super Charger on my 09 Z06 in February the first weekend I had it I to took it Houston Raceway park 1/4 mile and ran it. Just wanted to see what it would do on the track. After all it put 574 rwhp on the dyno at Corvettes of Houston where it was installed. I hit the rev limiter in 3rd gear and it suffer detonation, blow off a small piece of #5 piston and cracked the sleeve. I do not know if the sleeves are weak or not. We believe that WOT was set to poll to much timing, and at 11:1 compression and 7000 RPM's they were just to much. So after my nightmare I would definitely make sure my tune yes right, WOT because it will blow. Sorry!
 

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I have never heard of anyone putting a supercharger on a setup with that much compression. Everyone knows you mate supercharger to low compression. You didn't mention your tune. Did they tune your setup for supercharging at all ... what was the AF ratio? Was there any KR when you tuned and what timing did you adjust it to?
 

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I have never heard of anyone putting a supercharger on a setup with that much compression. Everyone knows you mate supercharger to low compression.
I have seen several C6Z's with a blower (they all have 11:1 compression stock) so the act of supercharging itself is not the primary issue IMHO. You're right about lower compression being a friend to boost but just having 11:1 compression is not a deal breaker.

The question is the amount of boost and the tune. Either or both of these would most likely be the culprit for the detonation.

Mike
 

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I put an Edlebrock E-Force Super Charger on my 09 Z06 in February the first weekend I had it I to took it Houston Raceway park 1/4 mile and ran it. Just wanted to see what it would do on the track. After all it put 574 rwhp on the dyno at Corvettes of Houston where it was installed. I hit the rev limiter in 3rd gear and it suffer detonation, blow off a small piece of #5 piston and cracked the sleeve. I do not know if the sleeves are weak or not. We believe that WOT was set to poll to much timing, and at 11:1 compression and 7000 RPM's they were just to much. So after my nightmare I would definitely make sure my tune yes right, WOT because it will blow. Sorry!
Those E-kits normally come with or require a higher flowing fuel pump and come with too large of a fuel injectors.
9 out of 10 times the failure is due to bogus tuning, worse is over sized fuel injectors mean the guy tuning has to be a pro or at the least do good quality tuning which is rare when $500 tuning products have allowed idiots to tune something they have no experience on with a $70,000 plus Corvette they made into a timebomb as it sounds like in your case.
Mose LS7 have blown up from bad tuning then by the design of it's parts

Would be cruel to push a LS7 with no cylinder walls, brittle sleeves in hot Houston heat with bad fueling or tuning.

One bet of crap tuning is on a chassis dyno as it lies more then tells the truth and the tuner is mislead to fueling at WOT since he is tuning in a condition where the car is about 600 pounds lighter then a static dyno drum so in fact engine as not requiring to pull the same load mass as in real world and PCM adjusts over time which is not allowed during less the 1 minute dyno pulls.

Higher engine compression is and with boost the higher the cylinder temps are and it is foolish to run boost with using water/methanol injection who's job is to yank temps out of compressed boost air and cylinder charge temps.
 

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Yes that is the moral to my story, if you Super Charger your LS7 the most important thing is to make sure you have a good tuner or all will be lost. I have since rebuilt my motor better and stronger, now it has forged 10:1 JE pistons, new coated rod and main bearings, the titanium rods where not damaged. the sleeve was replaced, ARP studs installed in the block, the heads where machined seats, and milled .005 for flatness. A trunnion upgrade, titanium seats. dual comp springs, Comp cam 625/239, the pulley on the super charger reduced to 1.75 dia. for 8 psi. of boost. Ram dual disc clutch. Corvettes of Houston tuned it on the dyno, a chassis mount dynopack it put 654 rwhp, and 705 lbs. of torque. It took 4 months to get this work done and I do not like the way it runs, or maybe that is the wrong way of expressing it , I don't trust it would be a better way of saying it. The same man tuned it this time as tuned it last time. I picked it up 2 weeks ago and have only put 100 miles on it, that is why I joined this forum to try to find out more about what I have and what is going on with this car. To try to find a hot shot tuner to check my tune and tweak it to perfection. I didn't start out to put so much in this car, but now I have a sizable investment in it and want it to be right. Come to find out after talking to 3 or 4 people locally my experience is pretty a typical, the consensuses is that most people that supercharge there motors blow the 1st motor, then it gets the respect it deserves.
 

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If folk are going to put a blower on a stock high-compression engine, I can se why they blow their engine fairly quickly. smh

Mike'sZ06 ... from a supercharger maker:

For Intercooled ProCharger EFI/TPI applications with compression ratios less than 9.5:1, boost levels of 14-17 psi can be safely run with full timing on pump gas, and will produce horsepower gains of 75-100% (depending upon the boost level and the motor specifications).

For 9.5:1 EFI/TPI applications running without an intercooler, boost levels above 5 psi will require the use of ignition/timing retard on pump gas, and will produce horsepower gains of 35-45%.

Boost levels above 12 psi should generally be avoided even with racing fuel on a 9.5:1 motor. Of course, lower compression motors will be able to run more boost, and higher compression motors should run less boost, everything else being equal.
 

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From a Chevy Perforance article:
Compression
The amount of boost you can run is directly related to an engine's static compresssion ratio. When the boost is combined with the compression ratio, the result is the effective compression ratio. Typically, a 5- to 8-psi boost range (usually produced with the supplied pulleys in blower kits) will work fine for compression ratios in the 8:1 to mid-9:1 range (operating on 91/92-octane fuel)
 

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Even Jegs article:

The amount of boost that can safely be run is primarily determined by the compression ratio of your engine and the gas that you are using. As a basic rule of thumb, the 5 to 8 pound boost range that is provided by the standard pulleys supplied in Weiand's supercharger kits is suitable for compression ratios in the 8 to 9:1 range when used with 92 octane gasoline. If your compression ratio is higher than this, you will have to run less boost. If it is lower than this, you can run more boost.

The key to any supercharger installation is that detonation must be controlled. Detonation in a blown engine is more destructive than in an unblown engine, and damage to piston ring lands (or worse) will occur if you continue to drive a blown engine that is detonating.
 

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If folk are going to put a blower on a stock high-compression engine, I can se why they blow their engine fairly quickly. smh

Mike'sZ06 ... from a supercharger maker:
I am more than familiar with Procharger. I watched the very first P1-SC install on a C6Z several years ago and several since then.

Nobody is talking about boosting a 11:1 compression ratio 427 sleeved engine with 12 pounds of boost. Not even 8 lbs.

Can the LS7 be boosted relatively safely at 4 or 5 pounds boost with a good tune.. YES.

Can you get the 574rwhp that akitchler spoke of with 4 to 5 lbs boost.. Yes.

Is proper tuning an absolute..Yes

Mike
 

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They are talking about boosting stock engines here, from what I can tell ... but, I think this discussion makes the point:

Compression Ratio/Boost Pressure
The compression ratio of your engine has a direct relationship to how much boost you can run. If you have a high compression ratio, such 9.5:1 or 10:1, you will only be able to run a small amount of boost.
... you obviously can't try to run 10 pounds of boost on a 9.0:1 compression ratio engine. This gives you an effective compression ratio of 15.1:1, way beyond our 12:1 figure. If you are building your engine from scratch, it is a good idea to try to build it with a relatively low compression ratio, such as 7.5 or 8.0:1.
 

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Can the LS7 be boosted relatively safely at 4 or 5 pounds boost with a good tune. YES.
I agree with this. Is that all the OP was boosting at? 4 or 5 PSI of boost?

If so, I would still ask if it was tuned properly for timing and air/fuel mixture.
 

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BTW ... I installed a D-1SC on my LS1 back in 2001 or 2002. I have run supercharged on my Trans Am since then. A safe A/F tune was never my problem ... my problem was that no one (including me) understood what transmission parameters to set to keep the A4 from over-rev'ing on a blown car with upgraded heads/cam.
 

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I agree with this. Is that all the OP was boosting at? 4 or 5 PSI of boost?
The poster I was responding to (akitchler) indicated he was making 574rwhp with his blown Z. That is well within the capabilities of 4 to 5 lbs of boost so I assume that's pretty close to where he was.

Mike
 

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Also, somewhere in this thread, someone suggested one would be taking a step backwards, or somehow creating a less desireable engine by installing low-compression pistions. If they believe this, their knowledge is limited when it comes to supercharging:

Additionally, you will make more total power with a low compression, high boost engine than you will with a high compression, low boost engine.
 
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