thnx binder.

won't a lower compression ratio not make it more difficult to reach my 500hp goal with a vortech?

you're talking to my builder right now (;

yesterday i picked up an engine with bearing damage (probably as it was still running) and i'm going to take it apart as a learning project. if it turns out the block and heads are reusable and if i feel confident i can rebuild it i will give it a try.

i know you will say i'm crazy for trying but the way i see it you won't learn if you don't try.. everyone was a noob at one stage..

i will do it myself or i won't do it at all.. that's my tuning rule (:

 

Hat off to you for gettin in there and getting your hands dirty. Truely is the only way you'll learn how. *remembers building first engine*

 

Great thread! Just wanted to share what im currently doing.

So i have the V2 blower and 2.87 pulley making 440 RWHP on a dyno jet at 12psi on stock block..

Been doing a lot of research and im obviously pushing it. I dont want to go the built engine route so i decided to decrease the amount of pressure on the engine.

What im doing to leviate pressure:
- just ordered stillen HFC's, Stillen headers and vortechs 3.12 pulley and belt.
- Im hoping to make 400 rwhp safely around 9psi...

Just thought i would share..

 

Larry??knew that was ur G!!

your car made great power, my 2.87 did 400+ . it could be your aggressive timing ? how conservative is it?

 

Hey Vas!

Not exactly sure but a guy next to me at the Uconn show was making 440hp with the 3.12 pulley at 9psi. Only difference was he had HFC's and Headers.

Is your car ready yet? we need to go cruising!

 

don't worry about a number. depending what dyno, what day, blah blah blah. There are a million factors. even everything exactly the same just 1 motor to the other could be an increase or decrease in 5% of poewr just how it came from the factory.

 

all other things equal lower compression motor will yield less power, correct.

now the issue is, unless it's a built block you wo'nt be able to handle high compression with high boost. 12psi vortech on stock compression will be ok. also it matters where your pressure is. Obviously a vortech is 12psi at rev limiter, a turbo could get 12psi down at 3000 rpms. High boost and low rpm will create more pressure which will equate more torque.

That's the reason most people who are boosting heavy from down low use low compression motors. Going from stock compression to 9.5:1 or 9:1 isn't going to lose 50hp off your dyno, but it will drop some hp IF you don't change anything else. Now with a lower compression you can run more timing so you can easily make up for that loss in power.

 

Here is the dyno chart from the Dynojet. I have to rescan the original tune chart from the mustang dyno.. cant find it on pc.

 

is that yours or the one from that other guy?

i was just saying that there can be huge variations in dyno's just between a stock verses stock car so i woudln't worry about your number if you go down in pulley size. You'll be just fine for power if you are looking to be a little more safe.

 

almost there!!! waiting for the turbo to get here... doing some exhaust and body work meanwhile

 

Yes that is the dyno of my car.. So its not about the #'s but the amount of PSI's? kid that did this dynojet pull brought it a bit past redline.. said i was at 13 psi

My stillen headers and hfc's should be here this week along with the new pulley. So what is a safe HP # to make? or is it all about PSI's? or would we need to compare this to a stock G's #'s on this dyno?

can post up my tune sheet too for hahas.

but dropping the pulley size is def a good idea right?

want my car to last.. till i get the itch to fully build and do twins

 

More body work? damn your car looked sick before.. lol

Cant wait till your car is done.. we need to cruise!

 

truthfully it's about torque numbers more than hp numbers. To get dangerous torque numbers with a vortech you need mid 400's in hp. now with a turbo setup you can get 400tq with only 400hp which would be a little more risky than a 380tq/420hp with a vortech. Torque puts stress on the rods which are weak.

If you want to be safe it would be wise to drop down to a 3.12 pulley. You'll still make great power and you'll be safer than a 2.87. With a 2.87 you might be safe for life with no issues, but a 2.87 is going to be "less safe" than a 3.12 (being both are tuned properly).

 

I see.. Well i ordered the heads, HFC's and pulley. Im going to get tuned again by John at Akuma motorsports on my Cobb AP.

Thanks for the info.. i think im gonna go the safe route for now.

 

you'll still make great power. your boost will lower with the headers and hfc but the peak hp will be higher. Boost is just a measure of resistance so it's not really that important.

Hell, you always can move back to the 2.87 if you want more later.

 

If i am making 350-400 whp it's not ok to use 91 octane? Is that what the Water/meth injection is needed?

Also I understand in the write up, it indicated you should have gauges for boost, a/f ratio and oil but if I change my oil every 3,000 i shouldn't have to worry correct?

Lastly with the kit, do i need to change the oil more frequently or 3,00 is good?

thanks

 

91 octane is fine if you tune for it. With 91 octane you will have a little less timing than running 93 octane. It's no problem. You could tune the car to run on 87 octane if you wanted. You'd lose performance by pulling that timing though.

350-400hp meth is no needed. Meth is used to cool and add extra octane for safety. Usually people run meth to increase octane therefore allowing them to increase timing so they can get more hp out of the engine.

The gauges aren't required but it's almost always a good idea to have an a/f gauge in the car. That way you can see during WOT if the car goes lean or not. If it's tuned properly you shouldn't need to monitor it but it never hurts.

Boost gauge, again, not really needed if you have someone else tune the car and you just drive it. With a vortech you aren't going to deal with compressor surge since it's driven by a belt so no need to really monitor it.

The oil gauge they talk about is oil pressure gauge. If you lose oil pressure for any number of reasons you want to catch that really fast and shut the engine down. if you have a stock gauge in the car it should be ok to use for reference.

3k miles for changing the oil is still ok.

 

Ok so like you said before its all about the torque #'s and the rods? So whats a safe level for the rods in torque? im assuming bringing down the psi's will overall be healthier for the engine as well.

 

correct.

I think most guys are staying under 400 tq to be safe. With 400hp on a vortech you're probably looking 350-375 tq so it'll be perfectly fine.

 

Thanks you, I don't think any gas stations around me offer 93 octane lol

so for that much power do you think it is safe or reachable running 91?

How much do meth go for, so that convert the 91 to 93? That probably means that it will cost more for gas

yea so ill just use the stock oil pressure, thats one of the three gauges on our car and get a/f raitio and boost