The rods arrived.
I'm going to start getting into build specifics for those of you who want meat with all this eye candy.
I purchased the CX connecting rods. I've never purchased any CX racing items before. I did it now for several reasons. The first reason was for me to check if they actually STOCK the parts they offer or if they are dropped shipped. The second is to see how accurate the description of their products is. Third they are the closest I could find to my beloved Eagle rods. Lastly is to check quality to see if I would be willing to purchase their bolt in turbo kit to use on a daily driver.
When the package arrived I wasn't too impressed with the way it was packed. All things fair however rods are probably tougher than any thing they may be dropped on during the trip here.
Just cardboard separating the rods.
I would like to have seen them shipped in a different way so there was no possibility of damaging the bearing contact areas, however they arrived in good shape. They were well packaged in plastic with good anti-corrosion applied.
Here are the specs from the CX racing website.
Forged Aircraft 4340 Steel, Highest Level of Strength, Racing Spec
High Performance, Supports 600 HP
- Rod Length: 4.803" , 122mm
- Piston Pin Dia: 0.787" , 20mm
- P.E. Width: 0.860" , 21.85mm
- B.E Bore: 1.772" , 45mm
- B.E. Width: 0.860" , 21.85mm
- Material: 4340 Steel
- Appr. Weight: 395(g)
- Bolts (Not Included): 3/8"
I don't like when they list horsepower however it sells rods better. Some of the more expensive rods only listed horsepower WITHOUT SPECS!
In summary CP pistons with CX racing rods are as similar as I can get to my typical JE piston Eagle rod combo, I normally use.
If engine specifics bore you, I have bad news, because here we GO!
First off we need to talk about fuel octane, altitude and how it effects engine knock. In Colorado our premium gas is 91 octane. That works fine in high performance engines with our 17-20% less oxygen then you have at sea level. In fact it makes engines run more efficient. For this reason most new car spy photos are taken here in Colorado. So car manufactures can show better gas mileage numbers on test cars. However there is always a trade off and in this case that is horsepower.
It's not only effected by the lack of oxygen but also by air pressure. At sea level you have around 14.7 psi atmospheric pressure here in Denver 12. On a normally aspirated engine those two factor can equal as high as a 30% power loss. Hence the appeal of boosted engines. So why not superchargers? More torque right? Well here we have another complication. Superchargers are a set speed not pressure. Which is fine if you spend all your time around sea level. However our roads are as high as 10,000 feet and we drive to sea level every so often. So you have a risk of not having your engine stoich. Many finely tuned supercharged vehicles will have to be retuned to drive to sea level. I need to take time here to step on a soap box and voice my frustration when I see bar boost gauges for this reason. Bar is a measuring device but it's cumulative, so one bar on a boost gauge is actually 2 bar. Take for instance "outer space" referred to as a "vacuum". It's not. It's a lack of pressure. Just like Cold isn't a thing it's a lack of heat.
Now lets look at turbos. They are controlled by manifold pressure without cumulative reliance on static outside air pressure (See airplanes
). Then all that's left to overcome is the oxygen % which a good aftermarket ECU can handle. And if you oversize your injectors slightly you'll be just fine when traveling to sea level.
Now here comes the real meat of the subject, hard numbers and testing. On most rally inspired engines (2.0L) we can see numbers as high as 400hp on our 91 octane pump gas. That's at a typical 10.0:1 CR nearing the high 20s psi boosted. Anything over 30psi and you will TYPICALLY get knock. For those of you who may be reading this and are new to engine tuning, octane is a rating based on the level of heat fuel will reach before combustion occurs. If the octane rating is too low, the fuel will ignite before the spark plug fires. In this event you have ignition while the piston is on the compression stroke thus shocking the engine internals possibly causing damage.
I don't want or care to daily drive a 400hp 86. It would be foolish with the snow we get here. So I feel that a low 300ish range is good to balance the intention of the car along with keeping the newer factory turbo cars in the rearview mirror. So you may be asking why i would choose parts like this for 300hp only. For me I feel like a Toyota should always be reliable ( I currently daily an EVO 9 nuff said). Toyota used to have a model of 75-80% of capability to retain reliability.
NOW we take all these factors in consideration and we arrive at this: I build the weakest of my components to be near the 600hp mark. Plan on it never exceeding 400hp at sea level with a daily HP of 300ish to the wheels at a mile high. I achieve this with bumping down the 1.6L from a typical 10.0:1 to A 9.0:1 to avoid knock. Boost to high 20s with injectors at around a 70% duty cycle. Hope you enjoyed this taste. I will show you more as I do it. CHEERS!