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Circle_Nine 08-28-2007 11:04 AM

Difference in Horsepower.
I need to figure a few things out, and I was wondering if anyone could help me???

I need to know the differences in horsepower between the following combinations.
(we'll assume everything is stock).

If a 2.2H4 has about 137 Horsepower, and a 2.5H4 has about 165. (sources from some random websites).

What would the horsepower be if you placed the 2.2 heads onto the 2.5 block (creating a higher compression)??????? They'll bolt right on and i've heard of people doing this, im just wondering what the horsepower gain would be. I have hydrolic valves in my heads right now but I'll get some solids soon.

LiL Shoaf 08-29-2007 05:33 PM

Interesting.. I'm running 2.0 heads on my 2.5 block but my compression was adjusted for higher boost levels.. Lower compression is normally better for Turbo charged cars as it allows you to push more flow out of your turbo which equates to higher boost levels and more power.. Now if your talking NA.. that's another story all together.. I can't get you the answer you want, it should require some simple math with the right equasions.. But it's only going to be a ball park..

Circle_Nine 08-30-2007 10:49 AM

Another problem i have is I don't know if i will gain more horsepower with the 2.2 heads because they are single cam with hydrolic valves. the 2.5 heads are dual cam with solid valves. eh. I don't know where to look for this.

mosc 08-30-2007 11:16 AM

I think you'd loose hp going to the 2.2L single cam heads.

dumdum 08-30-2007 11:56 AM

Assuming the single cam heads are 2V per cyl,you would definatly loose some flow.If they are 4V heads you might want to find out the valve sizes.

Circle_Nine 08-30-2007 01:46 PM

they are 4vs per. cylinder

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