Thoughts on Rebuild Route

Post by **Bryson** » Wed Mar 19, 2003 1:55 pm

Hey guys... Sadly my bank is crap and I've decided against my RB25 swap. It was probably too expensive for my blood at the moment anyways...so I am back to where I was almost a year ago.. rebuilding my KA and turbocharging it.

I have a 93 KA24DE with 165k on it. -The engine runs fine and does not smoke or burn excessive oil that I can tell. -It does have the timing chain rattle of doom.

I want to rebuild it instead of finding a lower mileage motor since it is in decent shape and I want to get forged pistons anyways. My Q is this... I have found a few rebuild kits online, the problem with them is that they include things that I don't think I need.

On top of that I am not sure exactly what I need to up on the bottom end to RELIABLY run 10-12 PSI( I know the KA can handle in excess of 15 stock internals, but I want this car to last me atleast 4 years). I have searched and read these forums for a long time so no USE SEARCH please.

If I just get a master rebuild kit , will the engine handle 10-12 RELIABLY granted proper fueling and tuning.

Or should I still get forged pistons.. and maybe have my rods and crank shot peened, magnafluxed, balanced, polished. ( I took these ideas from http://home.nc.rr.com/turbo240sx/engine.html )

and if so.. then what should I get in place of a master rebuild kit since I don't want to buy things twice..(pistons,rods,crank)

Also I ment to throw in this.. I know my transmission is prolly in sad shape after 165k, so I planned on finding a lower mileage one as opposed to having mine rebuilt (it currently smokes from shift bott.. though it does not grind.. slight trouble with 1st and reverse when cold) ANy suggestions or sources for lower mileage trannies?

Sorry if this is a long and maybe retarded sounding post. Thanks for help in advance

Post by **Bryson** » Wed Mar 19, 2003 1:55 pm

Awww man come on guys throw me a bone here I see people posting to toehrs and this one slippin down the list

Post by **C-Kwik** » Wed Mar 19, 2003 1:55 pm

There is no reason why a stock motor will not last long under boost as long as you tune it correctly. Keep the motor from detonating, and maintain the motor well and it should be fine. If you build up a motor, don't do it for long term reliability. Do it for margin of error. 10-12 psi can be done reliably even on stock internals.

Post by **Syntax360** » Wed Mar 19, 2003 1:55 pm

hey Bryson, i'm in about the same boat u are. how much on average do the the kits ur finding cost?

Post by **walsnart** » Wed Mar 19, 2003 1:55 pm

C-Kwik wrote: If you build up a motor, don't do it for long term reliability. Do it for margin of error.

Why??? I would want something reliable if it was my choice, anyways... doesn't margin of error create reliability on turbo apps?? Thanks...

Post by **C-Kwik** » Wed Mar 19, 2003 1:55 pm

walsnart wrote:Why??? I would want something reliable if it was my choice, anyways... doesn't margin of error create reliability on turbo apps?? Thanks...

Not necessarily. There is a difference between reliability when the motor is tuned right and perhaps with a small margin of safety. Remove detonation from the equation and forged parts offer little benefit, so long as the boost levels are within the stock parts' strength limits. If you were to say that you plan to boost some 20+ psi, it might be a different story as the power level may be more than the stock parts can handle.

Keep in mind the compressive forces(pushing) of combustion do not cause fatigue. It's tensile forces(pulling) that causes fatigue. But unless you are revving higher, this will not be an issue as the tensile load will be the same even under boost.

I understand what you are saying, but the margin for error is a poor fix to poor tuning. There is no part, cast or forged that can withstand sustained detonation. Certainly a forged/stronger part may withstand more detonation before a part failure, but the simpler and more reliable solution for a built-up or stock motor is to prevent detonation in the first place.

Perhaps I'll answer this question you asked in your first post:

"If I just get a master rebuild kit , will the engine handle 10-12 RELIABLY granted proper fueling and tuning. "

Answer: Yes, but so will the stock parts(assuming they are in good condition). The key here is proper fueling and tuning.

Post by **Bryson** » Wed Mar 19, 2003 1:55 pm

thanks C-Kwik sounds good... though I think even you are nuts to say that my 165k mile engine wouldn't do well to be rebuilt before being turboed...

With this in mind... which engine rebuild kits do people ehre prefer??

http://www.importperformanceparts.net/

has a complete rebuild kit with the timing chain kit as well for

429.00 or 529.00 depending on whether or not I want a new oil pump. Is this too high? Know of a better place? as far as fueling and control goes I am planning for that already.. I will be posting my expected purchases for some approval in a day or so.

Post by **WDRacing** » Wed Mar 19, 2003 1:55 pm

If all you really want is 10-12 psi, I'd really consider the following options.

Test the compression on your current motor as is. If it's good, then install the turbo and fuel system that will support 12 psi. The motor will will last plenty long enough for you to get tired of just 12psi. Boost is like heroin my friend, I'm a complete addict.

While your getting used to driving a forced induction car around, set some money aside and either get a new low mileage block and or save up for some forgies.

Now you can drive it however you want to, you can also up the boost. You won't believe the power differences when you start leaning the motor way out by adding boost. Then just swap out your new motor once you've blown up the old one. All the essential parts shouldn't be damaged if you blow up your motor. So your turbo and whatever else you bought will just bolt on to the new block.

I did this with 5 RB20DET's in my Skyline. Tons of fun...nothing like turning up the wick till she pops.

WD

Post by **Bryson** » Wed Mar 19, 2003 1:55 pm

Hey WDRacing never thanked you for taking hte time to post.. anyways thanks man

Post by **MikeMurphy** » Wed Mar 19, 2003 1:55 pm

WDRacing wrote:If all you really want is 10-12 psi, I'd really consider the following options.

Test the compression on your current motor as is. If it's good, then install the turbo and fuel system that will support 12 psi. The motor will will last plenty long enough for you to get tired of just 12psi. Boost is like heroin my friend, I'm a complete addict.

While your getting used to driving a forced induction car around, set some money aside and either get a new low mileage block and or save up for some forgies.

Now you can drive it however you want to, you can also up the boost. You won't believe the power differences when you start leaning the motor way out by adding boost. Then just swap out your new motor once you've blown up the old one. All the essential parts shouldn't be damaged if you blow up your motor. So your turbo and whatever else you bought will just bolt on to the new block.

I did this with 5 RB20DET's in my Skyline. Tons of fun...nothing like turning up the wick till she pops.

WD

WD for president

Thoughts on Rebuild Route

Thoughts on Rebuild Route

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