Raising compression in my 318

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Bergarn

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Hello from sweden. Im building a hopped up 318 dodge engine from 87, that is going into my 65 dart gt.
I read that it has a 9 to 1 compression ratio, and im curious if i can get forged pistons that works with my 302 closed chamber heads. Or if there is an easier way to raise the compression without spending a fortune.
Im all ears about any other info on these modern engines. Sorry for bad english and have a good day :)
 
English is fine, and yes, lots of ways to raise compression. Cheapest way is to cut heads about .040. Or, you could deck the block. Or, you could change pistons.
 
But my std pistons are already at top deck though. How do i know if a forged piston will work with my heads? :p
 
How's the quality of fuel in Sweden? You might not want to go much higher than 9:1 depending on what cam you use. The #302 heads are closed chamber and quite efficient. Does your engine have roller cam? There's a good chance it does. Another plus!
 
Fuel quality is good on the right station, 98 octane almost everywhere also. Yes it has a roller cam now.
 
Bergarn said:
But my std pistons are already at top deck though. How do i know if a forged piston will work with my heads? :p
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We don't know much about your engine, or what's been done to it, or anything else. I just threw out some of the possibilities of raising compression, because that is what you asked. If you've already made modifications to the motor, or if it's already been decked, then you need to list what you know.
 
When your pistons are already zero deck, why do want to put in forged ones?
What is your idea of hopping up?
 
I was pretty unclear on the backround, im building it from bottom to top, it is a bone stock 318 from 1987, my plans are to raise the compression and get another cam. I would like to squeeze out 270-300 hp with stock heads if possible :p
 
Im curious how the compression ratio can be 9,1 with closed chamber heads and flat top pistons, wierd smog magic
 
Bergarn said:
Im curious how the compression ratio can be 9,1 with closed chamber heads and flat top pistons, wierd smog magic
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Are you just announcing the advertised compression, or did you actually check it?
 
The engine was running bad when i took it out of the van, did not have a thought to check compression unfortunetly
 
Bergarn said:
The engine was running bad when i took it out of the van, did not have a thought to check compression unfortunetly
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Doing a compression test by turning it over isn't going to tell you what your compression ratio is. Doesn't work like that.
 
If you're at zero deck with a .039 head gasket and a 64cc chamber you're a little closer to 10:1 if not even more.
 
You're right my good sir, forgot about that. I mix my english words :p Perhaps i should measure the ratio before thinking about new pistons
 
Have those 302 heads checked they are known to have cracking problems!!!
 
Ok, good to know. How many ccs do the 302 closed chamber heads have on paper?
 
The chart I have say's 62cc for the 302. I would do some nice pocket work on them, good valve job, mill them .020 and bolt them back on with a thin gasket.
 
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