Just wondering what the max is on these engine...

if i was to run around 12-13psi would i be safe? with a intercooler and alcohol injection..

I know this is kind of a sketchy question, but im just looking for what some of you are running for boost levels...



The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

beyond 10 psi, i think it would be better to start doing some work to your engine. To tell you the truth, I'm really sure about alcohol injection cuz i never really payed attention to it. So I can't really help you with that but it would be a good idea to start enforcing your engine a bit.

well i was going to run 12-13 psi of boost and then while i am running that save up for strong internals... do you think i could get away with the 12-13psi?



The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

Depends on what kind of turbo, and how much you invest in proper tuning.





4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!

psi is not the number to base it on. cfm changes with turbo size. therefore I would say that you are safe to about 260whp with proper timing and fuel mods. anymore than that and you will snap something for sure. Or blow something up. People have gone as high as 275whp on stock internals on a 2.4. Eco has handled about the same so far if not a tad more. and I am not too sure about the other applications. But psi is not exactly what to base it on is all i am trying to say. You have to tune properly and know how much power you are pushing.


01 Z24 Turbo

Make sure to factor in your elevation, being in Calgary your air is a fair amount less dense than air at sealevel.
ie. at sealevel and 10lbs of boost your car might move the same amount of air as it does in Calgary with 12-13lbs boost.

With an intercooler and methanol injection, you're not going to have detonation problems, without a doubt. Even with mehtanol injection alone you wouldn't run into detonation.

But being supercharged, you have start factoring in the larger torsional forces that supercharger is putting on the nose of your crank (with the increase in boost).

As for mechanical failures on the bottom end, I'd be worried about the rods first. Keeping your rpm down will significantly extend the life of your motor, especially if its seeing 13 psi.

I remember seeing a website about a guy that would build insanely fast turbo/supercharged cars with stock/near stock bottom ends. Running 16-17psi on stock bottom ended ford windsors surprised the hell out of me. toohighpsi.com I think is the link.
He shows somewhere on that page of a way to build a simple, cost-effective water/methanol injection system operated by a hobbs switch.



2000 z24
1985 z28 http://www.cardomain.com/ride/825536

Skip - Yea my dad has all these calculations on this program for altitude and all this... as his job deals with compressors which turbos and super are basically... So he has a HUGE data table all set out with more calculations then i have ever seen ahaha so there is lots of thought going into this before we slap it on...

Also will be going with a E-manage unit and 440cc injectors with a T3-T04E Hybrid Garrett turbo and i cant remember what trim or A/R he figured out for my car since he was telling me all this at 1:30am... and its now 2:45am so some of this might not make sense ahah

We figured while my entire engine is Bone stock internally, we would go 5psi of boost coming into the supercharger (via the turbo and after a 1.5-2psi loss threw the charge pipes) and have my supercharger with the stock 2.8" pulley which gives me normally 4.5-5psi max with the altitude i am at and the end result was like 9.5psi of boost going into the engine.. and the Supercharger would only be spinning at 13,4XX rpm and Eaton suggests keeping it at or lower then 14,000 RPM.

**note when i go to lower altitudes i see higher boost**

Hope fully i don't see any knock (early detonation) as i will be ruining 94 octane all the time, and then the intercooler (30"x6"x3") and then the alcohol

I am just wondering though how hard these E-manage units are to tune? like i want to get it as close as i can at home before i take it to a shop...

ahah ok its now almost 3:00am so im off.. i hope made some sence up there... if not please forgive me



The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

If you see 1.5-2psi loss through your charge pipes, you need to work something out, because that's sounds ludicrous nowadays. Think 0.5-1psi on a nice setup with a good intercooler (you seem to have the funding, will, and knowledgeable help to attain this).
E-manage seems to be hit and miss with the J's. Some people praise them, and some can't get them to work worth half a crap. However, I think the latter are the ones who don't quite know what they're doing, and give up fairly easily (at least in most cases). I don't see any reason why the e-manage wouldn't work, but I don't have any experience with it, so take that for what it's worth...
I'd also like to note that I'm glad to see someone actually attempting a dual-charge setup. Hopefully you and your dad will be able to make it efficient. good luck.



fortune cookie say:
better a delay than a disaster.

now this sounds interesting I have heard of people running as much as 20 psi thru stock engines at the track but i cant tell ya for how long. good luck with your dual charge setup!



99 Turbo Sunfire GT | Ram 2500 | International Rollback | Mr Hanky the Suburban

well this is what we have set up right now for the 2.8" (stock) pulley keep in mind there is tones of calculations for each thing...

Case 4 - 2.8" pulley
1.32 SC CR
0.75 Turbo efficiency
7.00 psig turbo outlet
1.49 Turbo comp. ratio
2.0 psid pipe loss
5.0 pisg sc inlet
80.0 oF tcr inlet
167.1 oF tc outlet
82.1 oF sc inlet
0.1059 lb/ft3 - sc inlet
13814.4 M45 rpm
365.9 actual ft3/min - air
38.8 lb/min - air (actual)
37.8 lb/min - air (corr)
3.1 lb/min - fuel
494.3 cc/min injectors
319.2 hp @ crank
282.3 hp @ wheel
11.1 psig engine inlet
145.2 oF engine inlet




The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

Whiles its good that you're doing all the basic calculations on your setup. Remember that they will get increasing more complex when compounding two extremely differring boost sources (turbo/sc). I'm just curious, why go with this setup when you can achieve your realistic power goals with just the turbocharger?

Thast cool man I always dreamed of doing this but money is tight being im only 17. I hope to be turboed by spring tho.


Thanx Charles

Excidium wrote:Whiles its good that you're doing all the basic calculations on your setup. Remember that they will get increasing more complex when compounding two extremely differring boost sources (turbo/sc). I'm just curious, why go with this setup when you can achieve your realistic power goals with just the turbocharger?

actually all the calculations are with the compounding the two.. we didn't just add one to the other... trust me if you saw the calculations my dad has for this you would see, and yes they wont all be exact but they will be pretty damn close for only numbers...

Why you ask? because i would love to see just a turbo set up @ 7psi of boost make 270whp... every one said my supercharger would be a restriction.. but its not.. i cant find a turbo that will flow enough air.. No Garrett T3 turbo will flow even close to what i need.. i need between 35-41 LBS/min of air from the turbo... at a compression ratio of 1.49 i believe so

At 10psi on the turbo and the stock pulley i would be making close to 300hp at the wheels... now if i keep the 10psi at the turbo and go 1 pulley size down to a 2.7" pulley on the s/c'er i will be around 315whp... And look how low my boost is on the turbo still... Do you know any one boosting @10psi on a turbo making 300hp?

I know this will probably be hard to tune but it is very doable and will be reliable.




The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

*WARNING: Dont bother if you're not extremely interested in turbos and/or wish to prove me wrong about what I'm about to say.. *

While I'm on your side here (dont forget that) and would love to see a dual charged setup, unless your power demands were two to three times what they are, I don't think this is the best way to go. That is of course, unless you just want a dual charged setup or want to be the only person doing this on a jbody. Anyway, here's what you're really saying with the above calculations (as far as what you've said thus far):

You want to plumb your supercharger into the inlet of your turbo. The idea is that the supercharger will supply low rpm boost and the turbo will pick up later on for peak power output. The supercharger and turbocharger will act as a compounding compression setup. This will effectively MULTIPLY the pressure ratios, giving you a relatively higher output.

Well, OK. You can't really say the turbo is at 7psi and you're making 300hp... Compounded systems don't work that way. You have to consider the overall pressure ratio...

So with that in mind, I will save you $2000. You can achieve approximately the same result with a similarly efficient turbo at 15psi (1.98 PR), since that is in effect what your dual-charging system will produce (not counting pressure losses within the system). That should put you right around your power goal of 300HP, if not beyond. With the supercharger limited to a low boost, compounding will mostly be the result of the pressure ratio of the turbo.

To make up for the turbo lag, you can inject a small-middling shot of nitrous at low rpm. This way you'll not only save money, but you'll reduce the complexity of your system by an order of magnitude. You won't have to worry about intercooling between stages (if you had planned on it) and you won't have to worry about the parasitic losses of the supercharger, which I think you forgot to include in your calculations...

The point is, compounding compressors is a method to allow significant boost increases beyond what the efficiency of a single compressor will allow. But before you're ever able to make use of this, the entire car will have to transform. That means professional transmission work, axles, tires, EVERYTHING. At this point, you're talking full on race car and GM drag car budgets. I guess I'm trying to say that you don't need anything even close to a dual compressor setup to achieve your goals and beyond. So why spend twice as much doing it?

Now thats all stuff you didn't want to hear.. what about if you just have $5000 burning a hole in your pocket? Well here are some of my ideas for a dual charging setup..

1.) I like the sc/turbo idea, its very cool, original and trick. Besides you're not fitting dual turbos on one side of the engine.

2.) If you did go this route, you'd be almost forced (by principle ) to intercool the air before reaching the turbo, and then again after the turbo. We're talking ultra efficiency here.

3.) The multiplicative nature of compounded compressors allows for some really sick power. If your engine is built, you could achieve any power level you desire (limitations of physics still apply unfortunately). I think if you do plan to go this route, intercooling is of the utmost importance. Really, compounded compressors start to make ridiculous power when both compressors can raise their pressure ratios together. For example two turbos at 20psi each will produce an effective compression of approx 67psi! With the supercharger being limited, the compounding principle is also somewhat limited. This kind of goes way back to the designing board to ask the question, will you EVER even be able to use that kind of power? Let alone trying to control it without spending a fortune? Pump gas is out of the question too unforunately.. This is a significant hurdle to making serious power with this type of setup. You should have your dad do all the calculations to determine what kind of temps and such you're looking at, should you ever desire 600+hp.

The key question I think is, can you compound charge while intercooling after each compression stage and actually combust the mixture without detonating or suffering some other consequence of the potentially extreme temperatures resulting....

Sorry about the length, this stuff is just interesting as hell.

What supercharger efficiency are you using? From my numbers on a purely supercharged engine, the efficiency of the M45 and M62 (and all Eaton superchargers) are just too low compared to a good turbo system. A high estimate would put the number at 60% for the M62. The M45 is lower. I agree with Event in running a purely efficient turbo system if you have the means to tune it.

If you want a good supercharged engine, find an Autorotor screw-type supercharger. The OA2089 is just slightly oversized for the 2.2L-2.4L engine range. Adiabatic efficiency is in the 70+% range with full boost coming on at around 2500 RPM's. On a beefed up ecotec bottom end, 10 psi (intercooled) will give you and estimated 248 hp. And, there is room to grow, since the supercharger is more efficient and flows more than the M45/M62. Just a thought.

Quote:

I agree with Event

You mean Excidium??

ahah man soo many things my dad pointed out there that are wrong.. not to be an ass so please dont take that the wrong way... and yes all the compound stuff is calculated... all the heat is calculated, every single number is from a calculation...not just some gr12 math.. im talking like 20+years of engineering from my dad..

The parasitic loss of the supercharger alone is like 5whp... people have the wrong ideas about superchargers...

I know your not fully saying this will never work... but i do have LOTS!!! of people saying this will never work saying the supercharger wont flow enough... IT WILL FLOW MORE THAN ENOUGH... THE TURBO IS WHAT CANT FLOW ENOUGH.....

Any way im done ahah this is way i didnt want to tell any one about my plans...



The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

15 psi on a stock bottom end and holding.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...