Hey guys,

I'm from Germany, sry for my bad english. Just ordered the last eforce kit 1572 in stock ( with tune )from Edelbrock some weeks ago for my C6 Z06.. It arrives in 2 days. Problem is, that I have headers installed and don't know, if I have less power now with the edelbrock tune or if I maybe need a custom tune? Does edelbrock have special tunes for headers or whatever? Has anyone of you pros experience in that? I don't care about warranty..

Second question is, is it possible to upgrade the eforce with small effort, maybe a smaller pulley? Then need another tune? The reason I ask is, before I install the kit, I want to make the right choice and don't want to do the work again because of a pulley or whatever.

Happy to be here, would be glad about some answers, thanks

Nico

 

Yes, you need to have the car retuned with headers, even if you flash in the stock Edelbrock tune that came with the kit since it running headers.

As for the Edelbrock can tuned that comes with the kit, it's dials in a lot more TM to hobble the motor even more that normal, and what you are really feeling.


As for going to a smaller pulley, not really, since the LS7 is thinned piston liner walled to begin with, and it with it already having high compression, it not going to take a lot more pressure before it blows the motor.

LS-7 block and note the thinness of the liners next to each other.


LS9 block and note the thicker liners/cylinder walls instead.


To be blunt, on the LS-7 with the blower you have, about all you want to make is about 650hp mark. The motor is really able to make this on it's own N/A, so long as the motor can breath correctly (the problem in its own with the stock intake manifold being the choking point of why it does not make that to begin with). So with a blower on the LS-7, what you are really doing is allowing it to breath correctly to make that 650HP mark cleanly, without putting too much pressure on the cylinders instead.

Really, the re-tune is pretty much straight forward since the can tune you got it really way on the conservative side.

Want to make sure that the motor is not trying to run too lean (under 12.4 AFR) when on boost at WOT, then check the amount of spark retard that is going on with the canned tuned as it climbs in boost.
Note, you will make more HP about 13.1AFR, but fuel is cooling, and since you are not running a meth kit, leave the motor running fatter for the extra fuel cooling.
Again, the headers are causing the motor to run leaner to begin with, and if it runs too lean, then that will cause engine ping, and going to retard the hell out of timing over just what is being retarded for the blower to begin with. Once the AFR is corrected, then can advance the spark timing dwells on the fuel octane you running as well (both don't push it to the point that your getting detonation.
Note, the higher the boost level, the higher the needed octane to prevent detonation as well. This is where the Meth kit comes in, since it can push the octane levels much higher that the needed amount, push the water in the Meth mix helps to cool down the hot boosted air in the motor as well.

Once these have been resolve, then the next thing is to go into TM and re-adjust it. Again, the stock tune that set even more conservative to pull back even more instead power, to really hobbles the hell out of the motor in TM, so you won't roast the tires every time you get into the throttle.
Note, with a TVS-2300, you get liner torque from idle, all they way to about 5.4K rmps. Hence this is the reason that the TM is holding back so much instant torque on demand from reaching the wheels, since even off idle, you still have the ability to throw over 600lbs of torque to the wheel at idle.

As for adjusting the TM so is does not hobble at all like you would on a standard re-tune of a N/A motor, not the best best choice, since the with that much HP and torque at any given moment on demand, the car will get away from you just too quick instead.

To add, since you did get the kit with the can tune that if flashed in once the blower has been installed on the motor, give Edelbrock a call, and they may have an adjusted tune for the motor with headers. This will get you closer to what you want (will still be conservative though) but should at least get you on the right track before you start to think of letting a tuner loose with the car.

 

Your English seems pretty good to me.
The standard out-of-the-box Edelbrock E-force system (and the Magnuson kits as well) will come with a pulley which sized to make 5-6psi of boost on an otherwise stock LS7 motor, and the standard "canned" tune will be designed for that configuration.
However, as you seem to know already, your motor will make less boost (probably 1-2psi less) with the headers, due to the fact that the exhaust tract is now less restrictive that stock. You could gain this back by getting a smaller pulley from Edlebrock and aim for around 6-7psi to be safe. With a proper tune and good octane, that kind of boost cannot kill an LS7, IMV.
It's good that you have the Edelbrock base tune to start with, as that will come with the right injector data in it, but as already mentioned, the "canned" tunes can be improved significantly by having a professional tuner tweak it for your car. This would need to be done to adjust for the headers and any pulley change that you might do to recover some boost.
That can be done remotely, but to get the WOT tune right, you would need to get yourself a wide-band oxygen sensor kit and either HP Tuners or EFI Live to data log your car running under WOT conditions, in order to get the Air/Fuel ratio where it needs to be, which is around 11.5:1. These motors cannot survive long on an AFR higher than that, whether it's an LS7 or LS9 block. An AFR in the 12s when your on boost is asking for trouble.
For remote tuning, you could look into the EFI Live Autocal, which a few tuners on here like Chuck "CoW" (Corvettes of Westchester) use to remote tune their customers car thousands of miles away. This system is cheaper than the full-fledged EFI Live tool, and its easy to use and offers you the ability to data log your car and then email the log file to your tuner, who can look at the log and tweak your tune to dial it in to where it needs to be in terms of things like fueling, spark advance, etc. Things like torque management can be tuned down or tuned out very easily, and the ignition timing adjusted to optimum, etc.
In fact, if you need to tune your car remotely, the best person that I can think of that you should speak to is actually Chuck CoW, because he's done lots of E-Force installs on C6s and is a big advocate of Edelbrock generally. He could set you up with an Autocal and wide-band kit and most likely will know exactly which pulley you should use. He's somewhat controversial and a lot of folks on here like to bash him for his colourful/bold advertising, but I've met him in person and I've used his services, and I can tell you that he knows what he's doing. He may talk your ears off about your car, but that's just because he loves what's he's doing.
Good luck with it and please report back on your progress.

 

Thank you Sammy! We have made some changes to our AutoCal Wideband Setup and it's actually a bit cheaper if you order by the end of the day today

as I ran a Labor Day Tuning Special here on the forum.


Hey Sam.... Let me know the status of your Guest Room!!! I think you got a truck the needs a CoW BOOSTER! and I'm sad that summer is over up here....

Thank you and please call me when you have some time!

Chuck CoW

 

First I want to say thank you to the americans for taking so much time for answering and helping me! That's how I know the americans. In Germany it's offen not like that! Thanks.

That was an idea of mine also to ask edelbrock for a Header tune before startin the engine. But they damn have no email contact, english writing is no prob. But talking is a lot harder to understand but I will try!

The Problem is, I now have 2 opinions of two guys. I don't know what to do now. I just want to reach 660-680HP. Not RWHP. Dano you say no smaller pulley ( maybe engine damage ), CI you say it's possible and brings a little bit more pressure and power back with no other hardware changes. I now know, I HAVE TO do a custom tune. Maybe I take the offer with CoW. Maybe I search for a Dyno and pro for Corvette here in Germany. ( Little PROBLEM :-D ) But I want to build the engine in that way, that I get some HP plus or a little better Performance. Pulley possible or not? Don't wanna install meth or other things.

 

Thank you for taking so much time helping me. Thats how I know the americans. Not usual in Germany. Thanks! You say no smaller without other changes like meth? Correct? CI says it would work. Now I dont know what to do. Don't want to make other big changes.. And what is "TM"?? sry for my english and understanding bad..

 

For you the same as Dano. Thanks for the great americans tryin to help me and taking so much time. I just wrote Dano the same, he says no smaller pulley on LS7 without other changes, you say it works. now I don't know what to to. Thanks for the offer with CoW. Maybe I take that offer or tryin to find a dyno with Corvette pros.. ( Little Problem here :-D )

 

Hi Chuck. I still have the Autocal. Unfortunately, the guest room is currently occupied by an au pair from Italy, which I'm sure you wouldn't mind sharing it with - not so sure about her, LOL. I'll give you a call sometime soon. I need to talk to you about the Autocal/truck etc.

It would be good if you could offer our friend from Germany here some advice about whether he needs to go down in size from the standard E-force pulley to make up for the loss of boost from headers, and what he should do about the E-force canned tune, etc.

 

No problem. I'm actually not American though, but techniclly a British Overseas Territory national. I live on a small rock in the Caribbean (Grand Cayman), which is why I have to rely heavily on guidance from the good folks on here. I typically vacation in Germany/Europe every year though, as my fiancé is Bavarian, and I can't tell you how envious I am of you having a Corvette and access to the Autobahn.

You should talk to either Chuck or another Corvette specialist shop that has installed and tuned E-Force blowers on LS7. I only have personal experience with the 6.0 and 6.2 liter engines.
I am aware that the LS7 tend to take less boost than the 6.2 blocks, because of the bigger bore and thinner walls, but at the level of power we're talking about here, that doesn't come into play here, once it's tuned correctly. Don't get me wrong, you can damage or destroy any of these engines with a bad tune, even without a supercharger.
As you probably know already, Boost is simply a measurement of restriction building pressure in the intake tract, so any additional flow in the intake or exhaust tracts downstream of the blower will tend to make boost drop, even though power may go up. Hence the addition of headers will tend to make boost for a given pulley combination drop, because there's better airflow out of the cylinder.
The reason too much boost becomes a problem is that air temperature increases with pressure, so the more pressure the higher your inlet air temperature ("IAT") will get. This increase in IATs will tend to make your engine detonate or "knock" quicker with a given octane, and this is a destructive force.
But again, with good fuel (I think you should be be able to get 93-95 octane in Germany?), I can't see you ever hurting your engine with a single step down in pulley size, as long as you get right tune.
Put it this way, you need to figure out whether the Edlebrock canned tune works for you now anyhow, since you already have headers. It may work, but I doubt it will be optimized. If you had a stock LS7, then could probably run the canned tune and although there would probably be room for improvement, it would work.
The simple solution is to talk to someone who knows about this specific combination of engine and blower, who can tune remotely for you. Good luck and let us know how it turns out. A go-pro video of you blasting down the Autobahn would be nice too!

 

You all have to move here for racing "Autobahn" legal. And I have to move to you to live my dream of drivin bad *** american cars spittin fire, burnin wheels and everybody says, yeahhh.... If u act like yourself in GERmANY, you are a swagger, everybody Looks at you like planet of the apes. If you act like yourself in the US, everybody respects you... Don't know if u understand whatI mean in my words But everybody is welcome visitting me. no prob!

 

I checked it out with a german specialist. Not more than 650HP, or the sleeves on the outside cylinders will crack. You see it in dano's pictures. He said no problem for the edelbrock to make 680-700HP. But in Germany it will crack fast, because of often fast racing over 200miles on the highway and usual fast driving. He said I have to change the pistons in forged pistons, than it's possible because of lower compression ratio. Don't wanna open the engine, so now I have to live with 650HP. I will send a picture of the dyno sheet, if somebody is interested. Thanks for your comments