2.2L compared to 2.0L

[debo890]

i dont think so, there blocks must have been resleeved. the stock aluminum block cant handle that much. blocks that handle that much have iron sleeves or "forged aluminum sleeves?".

[PrecisionBoost]

Yes.... the cast iron block would not normally need to be sleeved but I'm looking at trying to make 650hp.

The AEBS sleeves have been proven to manage up to 55psi of boost when used in an aluminum block (such as a honda)

The sleeves are manufactured from a very high quality chrome-molly steel that is way stronger than the stock cast iron.

If I sleeved the cylinders it would take all the stress off the upper half of the engine because the block wouldn't be doing much other than holding the sleeves in place... the sleeves would take all the pressure.

The other reason I was thinking about sleeves is that I want to make the rod length vs bore (better know as rod ratio) higher so that the engine will be more efficent and have less rod angle.

Some guys will mill out a chunk of cast iron and weld it onto the block... then they bore everything out so that it's just like one piece.

I'd much rather have a solid one piece cylinder wall such as I would get with a complete sleeve... I would still have a cast iron piece that passed the oil and coolant through to the head but it could be attached via bolts instead of by welding it on (two gaskets)

[debo890]

[quote]The other reason I was thinking about sleeves is that I want to make the rod length vs bore (better know as rod ratio) higher so that the engine will be more efficent and have less rod angle. [quote]

intresting, expand on this a little please. also, efficent as in how?

[PrecisionBoost]

Well.... I just realized that I said Bore instead of Stroke with regards to the ratio.... So I will correct myself.... the rod ratio is the Connecting rod length divided by the stroke.

So in the 2.0L engine you have a rod length of 143.1mm and a bore of 86mm

So this give you a rod ratio of roughly 1.66

I'm now going to basicly quote from the book "Sport Compact Car Engine and Driveline Handbook "

You should be able to order it from any number of book stores..... mine came from Chapters.

**********

The bigger the stroke-to-rod length ratio the more dwell time the piston has around the TDC. This accomplishes several things. Since the piston is near TDC longer, the combustion event has a longer time to impinge upon the piston, allowing a better transfer of force to the piston, which slightly improves the engine's thermal efficiency. The longer dwell time also gives more time to fill the cylinders at the bottom dead center on the intake stroke and more time to scavenge the cylinder during overlap. Since the piston is accelerated more gradually away from TDC, there is less mechanical stress on the crank, rods, pistons and cylinder walls. Reduced rod angularity at the point of highest cylinder pressure, also reduces mechanical stress, as the piston has less side load, and therefore rubs on the side of the bore less. Higher rod ratios result in less velocity in the intake ports; there is a lower demand for the ports to flow as well, as there is more time available to fill and scavenge the cylinder. Conversly, this can also mean stagnant flow at low RPM, which is not good for low-end power production either. To increase the rod ratio some tuners are running a longer connecting rod, moving the piston pin up higher into the piston to allow this. Some engine builders are even running deck plates to raise the engine deck so a longer rod can be utilized. Some import engines have rod ratios as low as 1.49:1. 1.7:1 or better is considered good. The most highly developed four stroke engines in the world, Formula One and motorcycle engines, often have rod ratios of more than 2:1. many tuners of production engines are attempting to emulate this.

***************************************

Hopefully the good guys at Sport Compact won't mind my quoting this part of their book..... after all I am promoting it.

I will draw a diagram to show you what the difference in rod angle is.

[PrecisionBoost]

So on this diagram Piston A has the pin near the bottom and it has a shorter connecting rod.

Piston B has the pin closer to the top and a longer connecting rod

Angle B is smaller than Angle A so when the piston is being pushed down the ROD B will push more straight down than ROD A.

Also since there is less angle Piston B will see less force pushing it sideways which creates friction and wear.

[PrecisionBoost]

Hopefully you can visualize the difference between the two diagrams... ROD/PISTON B will stay at the top and bottom longer because the rod angle is smaller.

[daewooluvr]

so where are you going to find pistons and rods for this?

[PrecisionBoost]

The rods and pistons would be custom ones or ones from another engine.

For example.... the USA Ecotec uses the same 86mm pistions with a much higher pin location. You would however need custom connecting rods for this.

I was planning on extending the deck... so if I made the top surface of the block 1/2" taller I could use the same pistons but simply get a custom rod that is 1/2" longer than stock.

This isn't a problem for me because everything will be custom.... custom crank, custom forged pistons, custom forged rods.

I hope to have them all done by one company and then dynamicly balanced and blueprinted as a complete set.

Calculating the rod angle is a simple...

Imagine the point at which the crankshaft is pointing straight right on my diagram.... this would be when the rod angle is the highest.

Tan IA = 143.1/86
IA = 59 degrees

So the connecting rods internal angle would be 59 degrees.

So on my diagram the angle "A" would be 31 degrees since I was calculating the internal angle and need to subract it from 90 to get the outside angle.

Now if I were to extend the bock and connecting rod by 1" =25.4mm my new rod length would be 168.5mm

New rod ratio = 168.5 / 86 =1.96
TAN IA = 168.5/86
IA=63 degrees

So my external angle would be 27 degrees.

So by adjusting the length of the rod with a new deck height I would have managed to make my new setup 4 degrees more upright.

This results in less side load and more dwell time.

I'm at work now so I can't spend the time to crunch numbers.... but I will see if I can work out the exact difference in dwell time.

[debo890]

intresting. thanks for the explanation. let me know how it works out.

[PrecisionBoost]

Ok.... this might get a little over some of your heads but it took me a while to figure out this equation so I figured I'd post it.

First off I will give you the formula



Next is the diagram

[PrecisionBoost]

I'm going to put the formula into an Excel spread sheet and post the difference in piston height versus crank shaft rotation.

I will also pick an RPM level and calculate the actual dwell time to show the difference between several connecting rod length to stroke ratios.

[PrecisionBoost]

The spreadsheet was a monster.... about 2000 entries.

I guess you guys don't need to see the exact results....

With a connecting rod that is 1" larger (rod ratio 1.96:1 ) I found that it moved away from TDC about 3.5% slower and towards TDC 3.5% slower.

It accelerated very quickly in mid stroke where the crank is 90 degrees from TDC.

Given that it's 3.5% on each side it means that the total net dwell time at TDC will increase by about 7%

So basicly the piston spends about 7% longer at the top of the cylinder and bottom of the cylinder.

This is quite a bit more time to allow for better mixing and combution.

With a 2" longer rod ( rod ratio was 2.25:1 ) this moves up towards 13% more dwell time.

[Nathan]

The new Optra 2.0L has less power because it is a U20SED which means that it complies with ULEV emissions.

The more powerfull Nubira 2.0L was a T20SED so it only had to comply with TLEV emissions.

ULEV is way harder to meet compared to TLEV

Therefore a power reduction was needed by GM.

I'm sure it would be easy to reprogram the ECU but it would no longer meet current ULEV emissions standards.

I know that this post is almost 10 years old, but I am rather curious about this re-flashing.

My biggest question is where can I find the appropriate software to be flashed?

[gse_turbo]

There isn't any option to reflashing the GM/Daewoo vehicles before 2010 if I remember correctly. The current Cruze and Sonic models are getting pretty solid aftermarket attention but not for older models.

I've done a bit of research with British based computer conversions as well as conversions to a Cruze/Sonic but they cost and work involved is not worth it.

I just started researching the option of using Saab T5 and/or T7 computer and it seems pretty reasonable.

Aside from converting to a computer from another vehicle, the only options are piggy-back systems (if you're going turbo) or a full stand alone EMU.

[Nathan]

THERE YOU ARE!! I've been trying to get a hold of you about an under-drive pulley and strut bar.

but to stay on topic

There must be something proprietary about it.
I do know that there IS a factual way to re-flash, the issue: apparently it's written in Korean.