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Heads for a 5.3

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Old May 17, 2005 | 01:08 AM
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Default Heads for a 5.3

Hey guys, I want to put togather a head / cam package for my truck.
I want these heads: HERE
But I am told they will ruin my compression. So which heads should I get? Also, Is a head and cam swap really worth the trouble?
Thanks!
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Old May 17, 2005 | 09:17 AM
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Originally Posted by 2001Z71
Hey guys, I want to put togather a head / cam package for my truck.
I want these heads: HERE
But I am told they will ruin my compression. So which heads should I get? Also, Is a head and cam swap really worth the trouble?
Thanks!
i am nnot an expert...but from what i read, head and cam swap is difficult and expensive. not sure if those heads work. as for compression: low compression for FI and high for NA. they make amazing amounts of extra power, but are really expensive at the same time. i suggest you do bolt ons first unless you have already done all that.
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Old May 17, 2005 | 10:00 AM
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Can you do your own work or would you have to pay a pro?What would be your budget for a H&C gaskets,bolts,tune,ect.?Better question,How much are you willing to spend for all your future performance mods to your truck?
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Old May 17, 2005 | 11:55 AM
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Thanks for the replies. So far I have intake and exhaust. I am going to do my own work also.
I got antzy and bought the heads in the auction, I gave him a best offer of $350 for the set and he accepted it, totally unexpected! I plan on spending about $800 in total. Ive spent $400 on the heads, Im thinkin about $200 for the cam, and after that Im going to get a nelson tune.

I have been told that the heads will kil my compression. My question is will it be too low or too high?

Thanks!
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Old May 17, 2005 | 12:05 PM
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Maybe they can mill them for you
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Old May 17, 2005 | 12:11 PM
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He said he could mill them in order to lower the compression. Is that what I want?
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Old May 17, 2005 | 12:17 PM
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They mill them in order to make the chambers smaller to raise the compression. Can he figure out for you how much he would need to mill in order to get your compression in the area of 9.4- 9.8?
Based on your question are you sure you are able to handle a H&C install?
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Old May 17, 2005 | 12:22 PM
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LOL, I know I am not capable of installing them myself. I have a buddy who is extremely knowledgable on this subject and has built a few engines. FWIW, what am I looking at to get them porfessionally installed?
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Old May 17, 2005 | 12:41 PM
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You are going to have to mill those heads alot to raise compression
are you going the FI route or staying NA? thats an important question you need to answer before you decide how much to take off the heads. If your staying NA I wouldnt be suprised if you have to take .06 to .09 off those heads to get over 10:1
Oh and buy HP tuners it costs the same as a mailorder and I wish I had done it in the end you'll thank me. If your this far in you'll want to tune the truck yourself, its not as hard as you think just have to take your time and do alot of reading. Im interested to hear how those heads work out. Let us know what you decide.

Oh and on figuring compression the 5.3 pistons are dished I believe the dish is at least 3cc but I could be wrong, so youll want to figure that in.
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Old May 17, 2005 | 12:45 PM
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I wouldnt have them take any more than .030 off,I bet that will get you close to the stock 9.4 compression ratio.
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