Low Compression Results (Help Diagnose Please)

[BlackSpyderVR4]

^----If I wanted to just throw money at the car I would. This is my hobby and I enjoy this, I'm in no rush. I bought this car with the expectation of turning every bolt in it and tearing it apart and rebuilding it how I want. The only things I will not be doing is machining and any transmission work required.

[CoopKill]

If you are 120k or over do the oil pump. Do yourself a favor, and add up the parts to do the short block, add in the machine work/assembly cost, and compare to a Pampena staged block.

[BlackSpyderVR4]

I'm building the engine myself. It will for sure be cheaper. Even with the machining I don't see it approaching 2k, but that is one hell of a deal for everything being installed and balanced. For the stage 2 it seems like that thing should handle a lot more than 500whp though….

[mb3000]

He rates those numbers based on day to day usage. Imagine a 500whp DD, not just when you crank it up on the 1/4 mile every now and then.

[kywhitelightning]

If you are 120k or over do the oil pump. Do yourself a favor, and add up the parts to do the short block, add in the machine work/assembly cost, and compare to a Pampena staged block.

$700 + shipping for pistons
$500 for rods
$200 for wrist pins
$100 for bearing set
$180 machine shop cleaning and boring the block plus polishing the crank.
$65 New OE main bolt set
~$25 for new freeze plugs

~$1750 plus my labor for mine.

This is a build that is the equivalent of his premium parts list plus extras. I believe that if you are capable (tools and knowledge/formal training) of building an engine and honestly don't mind the time involved with the balancing and clearancing, it's a very good experience for the DIYer. The biggest part of the process is the time spent clearancing. Don't short yourself there, be patient and vigilant in finding inaccuracies and take your time to be thorough throughout the process and all should be well.

Jeff

[DocWalt]

^^ Your machine shop is very inexpensive...

[familyMAN]

Machine shop price seems about right for cleaning, bore and polish. Add $200 for balancing though.

[DocWalt]

I guess mine is expensive then, it was around $220 for that work + two jack shaft bearings replaced on my little 4 cylinder. Either way, cheaper than having it built for sure, but measuring everything is on you then. I was ok with that on my engine's loose tolerances and low power, but it gets significantly more important with tighter tolerances and more power. Make sure your measuring equipment is up to snuff.

[kywhitelightning]

They didn't balance the crank. Balancing all the components based on weights and then fitting them to the holes where the bigger pistons go in the bigger holes and the smaller pistons go in the smaller holes all while ensuring the rings end gaps are equal across the board was a lengthy process. Nothing in this world is a perfect fit so quite a bit of time was consumed attempting to make it better.

Even adding $200 to this process seems cost effective to the capable DIYer.

Jeff

[BlackSpyderVR4]

Going with Pampena's will be a lot cheaper for sure. Because I have so much tools to buy for this engine build (Micrometers, piston ring filer, ring compressor, cherry picker, engine stand, etc). Im expecting to spend at least a grand in tools. I figure I should go ahead and buy them while Im still only 26, I have a feeling my love for cars will not be going away any time soon so should be an investment. In the last 8 years I have already built 4 engines for my cars. I got spoiled using all my dads tools in his 3 car garage throughout my teenage and college years. BTW you guys always replace the freeze plugs for engines when you rebuild them?