KA24DE+T engine tuning plans (kinda long, sorry)

[Kitahara]

I have spent a bunch of time researching different possible engines (pros/cons/price) to go with for my next project which would be a 180sx fast back.  I have given consideration to the RB25DET/26DET(T), and the SR20DET and I was looking for a challenging but rewarding project.  I was more inclined to the RB's because of the challenge involved, 6 cylinders and originality points.  I liked the RB26 but the initial price, as well as the price of a custom turbo set up, drive shaft, mounts etc. makes me nervous.  Then again for the RB25, I don't like the intake manifold design (possible hood clearance issues) the compression is a tad high ($ to change that), and I would still be looking to upgrade the turbo set up which would be quite pricey as well.  

Therefore, I figured why not go with more reasonable options.  But rather than going with a SR20, like a lot of people are, I thought why not KA?  I can find a decent KA for a good price, and turn it into one hell of a motor.  The rod stroke ratio is nice, it's 2.4ltr, and in addition, the construction of the block is pretty strong.  With a little bit of internal work, I am thinking that the KA motor can become quite an overacheiver.

So I have sketched these specs up and I'm looking for opinions:

Stock KA24DE longblock
Bore up to 94-95mm & hone
Shot peen rods
balance crank
8.0/1 cr pistons
Thick metal head gasket (1.2mm+?)
Ported & polished head
Stiffer valve springs
720cc injectors
Upgraded intake manifold
Upgraded fuel pump
FPR
Reprogrammed ECU, or Haltech mgmt ($$<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>
HKS exhaust/turbo manifold
HKS GT ball bearing turbo (3040?...)
Custom down pipe
Custom intercooler piping
Large IC core
etc...
Stock KA tranny with VLSD

I'm also curious as to if adding oil squirters and turbo cams would be a cost effective decision in this layout. &nbsp;Hmm anything else?

My objectives would be to safely attain high boost levels, and ratings of over 400rwhp but not neccesarily more than 450rwhp. &nbsp;Thanks in advance for any feedback you guys can give.

[DSC]

Nice plan. HERE's (http://www.zilvia.net/pages/rides/s14.asp) a little inspration for a KA-T project.

Unfortionately nobody (to my knowledge) makes a metal head gasket for the ka.

IIRC, the ka already has oil squirters and I think turbo cam's would be a must to get those HP levels.

As for the rb25, you can modify its intake plumbing just like the ka-t's plumbing would be. Its a custom thing, but i've seen it done on the rb20.

[dsjunkie]

yeah like he said above it already has oil squirters....however for cams you'd probably get the best for your buck and best product for a 240 from jim wolf technologies.......OR if you like a challenge and a little something unconventional.....the 91 dohc in the 240 is know to have pretty agressive cam profiles....get an exhaust cam from the 91 and use it in your car as an intake cam (i think you'll have to redowl) but hey it's a bit unusual and i've heard of it being done so it shouldnt be TOO hard...well, thats my 5 cents :-)

[DuffMan]

Stock cams work well in turbo applications, but based on some of the stuff you listed (Port/polish, low cr, valve springs) it sounds like you are optimising your motor for top end, which would benefit from some aftermarket cams.

Also 400-450rwhp may be pushing it for stock rods, even when sp-ed.

[Cheater240SX]

Source for copper head gaskets...
www.paeco.com
They do a lot of custom stuff, though I have no idea of their quality. &nbsp;They also offer custom pistons. &nbsp;They quoted me $420 for a set.

Any ideas on fuel injectors? &nbsp;I'm shooting for 300hp with my KA-T. &nbsp;Need to address the fuel isue...

[s15dude]

Me and my dad have finally started our turbo KA project and are going to use a T3/T4, customize the stock intake manifold, custom exhaust manifold, custom intercooler piping, and the '91 cams, and JWT ECU and fuel rail with 550cc injectors. We are trying to make the most bang for the buck.

[Kitahara]

s15dude: Aren't custom turbo manifolds a bitch to custom make... would you be doing that on your own? &nbsp;Personally, I think I could build myself a downpipe and ic piping... but if it isn't as difficult as I think it is to build a custom turbo manifold, i'd love to find out how, so enlighten me if you would... &nbsp;It may be out of reach for me, although I do have access to a full machine shop.

Also, the T3/T4 set up sounds great for the money and I may consider that over the pricey HKS GT turbos. &nbsp;I figure I can always spec out ball bearing internals for the T3/T4, correct me if I'm wrong... I pretty much want quick spooling for autocrossing ability as well as great top end

As for copper headgaskets, what thickness would you guys go for when dealing with 400+whp applications? I figured around 1.2mm but I may be off the mark...