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Discussion Starter #1 (Edited)
As some of you may know last year my engine took a crap on me last year and needs to be replaced. I am looking into getting a cheap engine out of a totaled vehicle and have been tossing around the idea of upgrading the internals. I figured while the engine is out it might be a good time to do some mods. I am just not sure what to get.

I know the connecting rods are the weakest point of the stock components so I would definitely look at replacing them with some Eagle rods. Next comes the pistons. You can get them in 8.9:1 or 10:1 and not sure which would be best. If I am not mistaken 8.9:1 would be best for an NA setup and the 10:1 would be good for a FI setup. I have always dreamed of getting a turbo one day but its probably not practical in the foreseen future. So NA is probably the better option for me at this point.

Next comes the cams and gears. I don't have much money for this build right now so I think this is something that could possibly be done down the road with some stage 2 cams or something. As for the adjustable gears I am not sure if they would help me out in this scenario or not.

I have also heard good things about the Bates engineering stock replacement valve springs and again think this is something that could probably wait til i do the cams. When reading about these I saw something about needing special seals for the valves when using these. Does anyone know what I would need or would it be better to look into a different set of valves as well.

To sum it up I will probably due the upgrades in 2 stages. Rods and Pistons then the rest of the top end later. Does anyone have any idea what kind of HP a setup like this could produce with a good tune?
 

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10:1 for N/A.

Lower compression would yield more room for boost.

If you plan on staying N/A, don't expect anything over 200WHP, really.
 

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Discussion Starter #3
Ah ok. Guess I got the ratios mixed up. It would probably hurt performance to run the 8.9:1 pistons without any type to FI.
 

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For an NA engine, you generally want to bump up the CR as high as is safely possible. 12:1 or 13:1 would make you some good power, but you may run into detonation problems, even with high grade gas. If that's where you want to go, it will have to be custom, and meth may be necessary to run it safely. E85 I think should be able to handle it.

Talk with Leveecius, he's walked me down this road once before. Good luck.
 

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I have 10:1 on my 2.2L and have good mid to high range HP/Torque. I can really gauge the low range right at the moment due to some fuel vapor issues I'm having, but before the accel wasn't bad, not great.
 

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I have 10:1 on my 2.2L and have good mid to high range HP/Torque. I can really gauge the low range right at the moment due to some fuel vapor issues I'm having, but before the accel wasn't bad, not great.
Correct me if I'm wrong but doesn't the 2.2 L61 have a 10:1 CR stock?
 

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8.9:1 is low for n/a and would dog performance
Agreed. Lower compression or Dished pistons/bowl type are for forced induction, mainly turbo compression. Most turbocharged factory engines range from 8-9:1 to accommodate boost.

N/A you would go with what Plain Jane said, 12:1 is the best compression ratio for high rpm range power. So the other the offer is better or look around for a 11:1 ratio which is better than 10:1.
 

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I honestly think if the tune is in check and you're watching everything carefully, high compression boosted setups are fantastic. Most of the pushrod V6 GM guys are running 9.4:1 or higher in boosted setups, especially the pre-gen 3.8's. Top swaps for example are very common in many platforms, and will make the same, if not more power on the higher compression with quite less boost than it's factory boosted counterpart with lower compression. Less heat, less parasitic loss (if supercharging), so there is less chance of heat-soak/detonation...as long as the tune is in check like stated earlier. I'd rather have a higher comp. motor, since you'll make more power when out of boost as well. Keep in mind though...things just as KR and pre-detonation are exponentially greater on higher compression...so that's the chance you're taking there. As 1*~ on a low comp. setup of knock retard, might be equivalent to 4+ on high comp. business.
 
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