Low compression pistons

[BlackFox]

Who has low comp pistons in their KA? like 8.5 or 8.2

I plan to put low comp pistons in and I need some info. I want to do most of it in my garage, except the actual boring of the block, do I just take the engine apart and take the block to a shop to get it done? Is it that simple?

What brand of pistons do you have? What about conrods? Piston rings (size, brand)? Seals that should be replaced and where to get them? Price to get the engine bored out?

I'll be running 14psi, maybe more on this setup (how much HP could it handle? assuming everything else is setup), I got the fuel and stuff planed out already, I just need some info about the pistons and stuff. I know this is a lot of stuff to read, thanks for your help &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

[geeaj]

Yes, you should take it to a machine shop and have them hot tank your block, measure your bores, rebore if necessary, and install the pistons.

Regarding the connecting rods, Nissan rods are forged from what I recall. There is no need to go aftermarket. If you plan on making in excess of 350hp, I would suggest you have the rods raced prepped. This usually entails balancing the rods as &nbsp;set, shotpeening (to remove microscopic stress fractures that develop over time), and deburring and polishing of all rough edges. Some even lighten the rods. For a street turbo motor, I see no reason to go aftermarket such as Carillo, for rods.

[BlackFox]

What about pistons? who makes good ones? Should I lower the comp ratio to 8.5 or lower? Where do I get the pistons, rings. etc....

[geeaj]

JE, Aria, Nissan Motorsports are among some of the choices that you have for pistons. The cheapest would probably be Nissan, JE and Arias, I would imagine to be in excess of $500 for a set of slugs.

Rings, Nissan Motorsports sells a Chromoly ring set which is supposedly pretty good. Other choice is Total Seal, but I believe, as well as many engine builders, that this is overkill for the street. About $100 a set give or take a few dollars. Be aware that non stock pistons will have different rings sizes, architecture, etc. So be sure to have the piston specs ready for your rings. Best thing to do is get the pistons first, then the rings. Or buy everything from one shop.

[mbmbmb23]

Ive heard that you wanna have all parts on hand before you take the block to the shop to have them prep it. &nbsp;Then, have them "race prep" them and install them for you. &nbsp;This way you wont get the block home, and find something isnt to spec. &nbsp;Dunno what it costs to race prep tho? &nbsp;Anyone?

M

[geeaj]

Race prepping is a generic term. One shops interpretation of race prep can differ from anothers.

Generally, race prepping includes the following services:

- match balancing components
- lightening of components, includes deburring and grinding away surface impurities.
- Magnafluxing, ie, checking for stress fractures
- shotpeeing or some sort of technique to improve the structural integrity of the part.
- custom mods such as drilling larger lube holes

Expect to pay $$$$. Nissan tends to overengineer their engine components, so for the weekend warrior/occasional strip or track junkie, this is not necessary. IMHO.