kpturbo

iTrader: (1)

Hi.
Is there anyone here that running with high compression (11:1) and boosting with a Vortech here? Im wondering how much boost you are running without getting detonasjon?

Yes I have searched around here

cashmoney03

Not much. Boost and high compression don't mix.

Conway_160

iTrader: (1)

You running pump, e-85, race gas? All of that will play into how much boost and timing you can run

kpturbo

iTrader: (1)

Well thats not the case. It depends on what fuel you are running. With E85 you can run pretty high boost on a high CR. In my case im going to use pump gas as far as possible and then some water injection to get more boost. Im not going to use a water/meth mix, only pure water. Norwegians seems to like to drinking Meth here so it difficult to buy it here because of this, I know we are wierd
Im just trying to figure out how much boost you can run on only pump gas before you need water injection.
I know I can just buy some 9.0:1 pistons but I have already the 11.0:1 pistons here because I was going to build a NA engine, but plans have changed.

kpturbo

iTrader: (1)

I just found this post by Z1 performance that answered my question almost.

Originally Posted by Z1 Performance View Post

The only real valid comparison is what other Z's make on that dyno as well. Otherwise, I wouldn't sweat it. The dyno is a tool, it's not omnipotent.

For compression, the difference between 8.8 and 9, is indescernible.

Yes, you can use 11:1 on a S/C car, and even a moderate turbo setup. You're talking a modest increase vs stock...nothing earth shattering. It is not "too high" - the net result will all be in the assembly and tuning, just like it is with any setup. The higher the compression, with boost, the lower your margin for error as far as tuning, but the supercharger affords you a fairly easy setup to tune in the first place. His boost threshold and overall performance is going to be somewhat limited by virtue of where he lives and the weather there. More than a guys have boosted their stock HR engines, with alot more stress (and revs) vs what this setup would be (you can only rev the S/C setups but so high). So given that a stock HR compression is 11:1, a DE setup, with proper forged internals, balanced and blueprinted as any built motor should be, there is no reason 11:1 would not work well for this setup. If it were me, I'd also consider a proper water injection system as a 'part 2' to this build...once the engine is fully broker in, tuned, and running where you're happy. I think it would give a good safety margin and a good addition for your setup, and help combat the high AIT I'm sure you get.

Jaxter

iTrader: (3)

I ran 13.5 psi on my HR Stillen/Vortech for a while. It is not my daily driver so everytime I get in the seat I am in boost. I was running 93 oct plus 100% meth on a conservative tune at around 425 hp MD (probably 475 Dynojet). I broke a rod on the stock motor after swapping in a Si impeller with the same pulleys. We saw 15 psi 1000 RPMs before redline and over 450 hp MD when it broke.

I'm not speaking for OldmanZ, but I have read his posts before saying he would be interested in 11:1 CR when he has to build his motor. He is our most informative Vortech guy.

cashmoney03

I know all about the type of fuel and yadda yadda. Doesn't change the fact that they don't play well together. It can be done but your margin of error is tiny. For a dd I wouldn't recommend it even with water. To many variables at work to try and be safe and consistent.

Jaxter

iTrader: (3)

Another thing to think about is the maximum CFM that a Ver 1, 2, or 3 Vortech can put out. They are small superchargers. If you go too low CR, will the charger be able to push enough air to make up for the power lost to the lower compression? If you do go 8.8:1 CR, will you have to jump up to a Ti or YSi head unit to make any power? I don't know much, but in my experience, I'd rather go 11:1 and 1000 CFM for 450 hp and good power under the curve. Instead of 8.8:1 and ???? CFM for the same power with less low-end and mid-range. Just food for thought. Again, I'm new to this game, so I might be off base.

str8dum1

iTrader: (11)

you obviously dont know about fuel types.

the most common build in the supra world now is a 10:1 engine on a 67+mm turbo pushing 30-40psi on E85.

You have a much higher margin of error since you have the compounded octane and cooling effect of alcohol.

Once you get above 70% ethanol, most tuners will run turbos all in.

For example:

OldManZ350

iTrader: (23)

I have a 2003 350z Touring, Stock Vq35de motor 10.3CR making 16-17psi on 93 octane. NO water/meth injector. 42,000+ mile with Vortech, 50,000 on car.

Florian350zATI

Hi, I'm from Germany and have 11:1 with 102 octane and an ati prochcharger with 0,55bar@6800. EGT below 850°C.
i have 445hp.

more info from my building to: https://www.facebook.com/350zProcharger

2bad240

iTrader: (6)

I added you and sent a message