qg18de vs qg18dd

e2001gxe · Oct 23rd, 2002, 02:59 AM

what's the diff between the de/dd? anyone know how they got 126hp/129 tq vs 130hp/128 tq? emissions maybe?

Oct 23rd, 2002, 10:13 AM

where did you find out about the DD i have never heard of it.

Oct 23rd, 2002, 10:25 AM

Did a little web surfing.
http://www.nissan-global.com/GCC/Japan/NEWS/253a.htm

This link talks about both engines but doesnt really give a straight comparison.

e2001gxe · Oct 23rd, 2002, 12:50 PM

Yeah I saw that link. Apparently the difference that I can tell are the Hyper CVT or something. But I found out about the qg18dd from the engine matrix over at freshalloy.com thanks chris.

James · Oct 23rd, 2002, 01:02 PM

It says it's a direct injection engine.

Oct 23rd, 2002, 01:44 PM

http://www.edmunds.com/news/innovati...6/article.html

HYPER CVT
Basically what it is a "continuously variable transmission" which allows better gas milage, mainly for auto or autostick, instead of the use of a combination of gears, friction plates, hydraulic fluid and a torque converter it uses belts and pullies. These are only available in Europe and Japan, according to the artical, it also says they are for use on cars 2.0L or higher.

Direct Ignition Engine
By contrast, a direct-injection system allows exact control over not just the amount of fuel entering the combustion chamber, but when the fuel enters the combustion chamber. It even controls the shape of the fuel charge and the flow of air inside the combustion chamber! The benefits of all this precision can get pretty complex, but the short answer is that direct injection allows each tiny fuel molecule to be used with maximum efficiency, thus resulting in better horsepower and gas mileage. It also allows for a complete fuel charge burn, even when unburned exhaust gas is re-circulated back into the combustion chamber, which means reduced emissions and cleaner air.
http://www.edmunds.com/news/innovati...8/article.html

That is the low down on the QG18DD. It sound like they wanted top performance while maintaning good mpg on gas. This is the euro/japan QG.

Oct 23rd, 2002, 02:37 PM

Engine: Euro/Japan
Type QG18DD(NEO Di) , DOHC, Inline-4
Displacement (cc) 1,769
Bore x Stroke (mm) 80.0 ?~ 88.0
Max. Power (PS/rpm) 130/6,000
Max. Torque (kg-m/rpm) 17.7/2,800
Compression Ratio 10.5:1
direct-injection gasoline
Transmission:HYPER CVT

Engine: USA
Type QG18DE, DOHC, Inline-4
Displacement (cc): 1769
Bore X Stroke (in.): 3.15 X 3.46
Horsepower: 126 @ 6000 RPM
Torque (lb-ft): 129 @ 2400 RPM
Compression Ratio: 9.5
Fuel Type: Gas
Transmission: 4 Speed auto, 5 Speed manual.

Hp, Torque and bore stroke will need some mathmatical convertions to make the right comparisons.

Look at there compression ration.......what does that mean?

GXEman · Oct 25th, 2002, 05:20 PM

Why couldn't we get that engine? Cleaner emissions and more power.

http://www.freshalloy.com/site/featu...nes/home.shtml
Here is a link that shows the engines in Nissan/Infinity vehicles. The QG18DD is in the 1999+ Sunny.

http://www.freshalloy.com/site/featu...me_codes.shtml
And with this link, you can learn to read Nissan engine codes.

johnk · Oct 28th, 2002, 09:04 PM

There was an article about direct injection in November SCC I believe. It sounds great, and there are a lot of tuning things they can due with it for emissions and performance. They said the reason that none are sold yet in the US is that the gas isn't good enought, though Mitsu may be trying to sell one shortly. I believe the problem was sulfer? If thats the case, maybe they will sell them in the Peoples Republic of California sooner, since we already have to pay more for low sulfer gas.