Broaner and I are discussing the midrange power loss from running a 3.5L on the 3.0L ECU due to the 3.5L's cams having too much lift. I've browsed through many posts but haven't come up with any good graphs to look at. Maybe there haven't been many 3.5L swappers make it to the dyno yet?

Anybody looked into this yet?

thanks,
allen

 

Only one has posted... and it was an auto....

Only 2 forums up is where they post semi-regularly(some of the swappers)

 

I will hopefully dyno after I install my new clutch and Hotshots.

I do noctice a surge in power after 4k, but I also don't have my VI hooked up..

 

Still haven't hooked it up? Surge in power will increase with it hooked properly, but will also drop @ 3.8k and give a somewhat placebo effect.
Cannot wait to see your dyno. .

Is there a timeframe on this?

 

I don't really see this as a downside, really, it just makes the car easier to launch and the delivery is smooth and gradual. I have driven a '04 max but it's not really a valid point because of the 600 lbs difference. At some point when you have a FWD car, it's better to transfter the power to the upper rpms in order to actually be able to use said power on the street.

 

is it possible to flash the 3.0 ecu with the maps from the 3.5 ecu?

 

Just like what Tilley did with his n/a 3.5L set-up.

But for us auto cats, it's different.

 

Autos are real easy to launch anyways.

 

3.5L is still tricky compared to 3.0L.. But not with my VI disabled on my 3.5L,

 

Did you run the 14.0 with your VI not hooked up?

 

Yes. 10char

 

How much would you estimate a working VI would improve your times?

 

Yes the 3.5 cams are pretty peaky without an operating VTC system. What do you plan on doing to remedy this?

 

Thats what I was saying. The high lift makes it all top end without the VTC. Without working VTC its just gonna be more powerful because of the extra displacement and slight bump in compression.

 

Not with the sh!tty stock Im.

 

From the dyno charts that I've seen the 3.5L makes peak HP at about 6K RPM, if the stock 3.5L cams are designed for top end power then I should still make the same peak HP w/o VTC. The VTC's apparently just bump up the midrange power/torque. So, yes, I'll loose some "area under the curve" which is a bummer for drivability but honestly, it's not going to be that big of a deal. I'm replacing a tired 2.4L w/ a fresh 3.5L that has about 100 more HP and that much more torque too, this car's gonna fly w/ or w/o VTC.



I'm new to the whole standalone EMS world but I'm hoping that I'll be able to get most of the midrange torque back by tuning the ignition and fuel maps. We already know that the VQ's benefit greatly by advancing the base timing (w/ Consult) and also by advancing the ignition timing (w/ an AFC). So, w/ total control I should be able to extract the maximum power/torque at all rpms.

I hope.

allen

 

Curb weight is your best pal. Since I'm gonna drop my weight down to 2700 lbs for next year and swap the final drive ratio for one that is 17% more aggressive, I don't mind the fact that it's got less midrange and IMO shifting the powerband betwen 5000 and 7000 is the way to go for traction on the street (ok, we don't have a 1st gear, that's a given, but dead hooking in 2nd is REAL nice). That's why I'm going for a short runner'd, big chamber IM.

 

Do you have the IM yet or are you going to build a custom one?

allen

 

Might make some Individual throttle bodies using EU w/MAP instead of MAF

That lower intake manifold is just crying out loud for this.