Built engine questions

[mrbean]

I plan on (eventually) doing a ka24e-t. Supposing my stock engine is in very good condition:

1) If I plan on using high boost, what parts should I have replaced with forged? Which are the most important?

2) Has anyone used realnissan parts? Are their turbo kits and engine parts any good?

3) If I upgrade to forged pistons, should I change the specs at all? What's an optimal setup for high boost?

4) I know you probably shouldn't exceed 12 psi on stock internals, but with a reasonably well built engine, what amount of boost could i safely run?

Lastly, does anyone know a good auto/metal shop in the SF bay area that could possibly fabricate parts (experience with KA's preferable)?

I know its a long vague list of questions, and for that I apologize. :help I've tried to read the forum posts, but there are so many diverse posts on the different parts, its hard for me to get a big picture. Any help would be appreciated. Thanks!

[andrave]

1) pistons and rods, piston rings, clutch would all need beefed up... read through a few other posts and you can see exactly what some of the higher psi players actually use on their cars.

2) yes people have, I havent personally, only heard one complaint and that was that a manifold didn't fit the turbo properly.

3) thats up to you, you have the option of keeping the stock size or overboring, or keeping the stock compression ratio or going down. There are pluses and minuses to each, it just depends on what you are planning to build, how close to the edge you are willing to go for power, and what kind of shape your engine is in.

last question, no clue I'm from WV

quick tip: it IS hard to find answers by reading the forum. But you can conveniently search all the posts in the forum by using the search button, it usually saves time and a lot of time answers questions before you even have to start another thread.

[mrbean]

I have used the search function, and it has been most helpful, but oftentimes, it still required looking through 11 pages of results, and a lot of unrelated threads...

Some thoughts on your reply:

- Would custom headwork be required to withstand higher boost? Or is that for performance enhancement only?

- I know overboring pistons increases displacement, but what does that DO actually? Increase torque? If you overbore but keep CR the same, wouldn't that just keep everything the same?

[Nathan]

For your first question:No, headwork is NOT necessary as long as you plan to maintain a stock, or near stock redline. Headwork only makes the engine more efficient and helps it perform better (port and polish, oversized valves etc.) A lightweight valve-train will help your ability to rev higher as well as will stronger valve springs etc. but as I said, it's not necessary, just nice if you can afford it.

Your second question:Overboring does increase displacement, but not by a significant enough amount to matter. Unless you plan on sleeving the block you will not be able to gain enough eisplacement through boring to gain you any big enough amount of power to justify all the work imo. The best reason, and the reason I had for overboring is to start over with a fresh cylinder wall surface after it is bored and honed. This will help new piston rings seat and generally makes me feel better This is also why I went with practically the smallest overbore possible, a .020. Dont forget that when you overbore you are taking material out of the walls of the cylinders which makes them weaker, overbore too much and you could have problems. Overboring but keeping the CR the same would for the most part change nothing, it might increase power levels some miniscule amount but not enough to really justify it.

[WDRacing]

Overbore increases the CC of the engine, just comparing a 305 chevy to a 350 chevy. The overbore on the KA will not yeild much of anything do the fact you can only over a small amount. Not enough to actually make a noticeable difference.

Let me ask you a few questions before I go about answering anything. What are your hp goals?? What is your budget?? Are you going for a road track car or drag??

WD

[mrbean]

This will be my daily driver, so has to be completely streetable and no long periods in the shop

HP goal - As much as I can safely pump out! But seriously, aiming for somewhere between 300-350 whp.

Budget - 5-6 grand for complete turbo setup and any engine work needed.

I'm looking for an above average sleeper I can take to the tracks once in a while. No drag (at least not yet... )

I would be willing to sacrifice shop time to accomplish my goals. Are my goals reasonable? Too much? It doesn't seem TOO impossible if I have the right setup planned before I start. Engine work shouldn't be too extreme, right?

Thanks for all your input so far. This has been most enlightening!

[Nathan]

Actually, I think your goals are attainable, they are pretty much exactly what mine were and I am one step away from being done with the engine build and turbo setup for right around 6 grand.

[mrbean]

Hey Nathan,

What kind of a setup are you running in terms of the turbo and engine work? If you've already got it posted somewhere, just lemme know where to look. Also, how much custom work did you have to do or have a shop do?

[WDRacing]

No internal work is required for 350 hp...Just fuel, boost and timing. Of course if you have an ultra high mileage KA and want to do a rebuild, you can always swap the rings and seals and hone the block yourself. Its alot cheaper that way. But you don't need forged internals to achieve your goals. If you want you can hit me up on email, [email protected] I'm always more then happy to help out a fellow boost junky.

WD

[mrbean]

WD- Engine's good. only 88k when I got it. Runs smooth, just have to get it checked out to confirm. I know the ka24e's are cheap to replace, but I just can't afford to not have a car for a while, so preferably I want my setup to be a bit on the overkill side, just to be safe.

What psi boost do you think it'll take to make 350whp? If stock is around 125-ish whp, I'll be trying to add a good 225 extra. If I can expect a (generous) estimate of say 10hp per 1 psi boost, that makes it about 22-23psi. Isn't that way too high for stock internals? Am I missing something out of the equation?

[Nathan]

Well I know i've posted it before but I'm entirely too lazy to try to find it again so here you go:

Block:Ross Racing 8.5:1 pistonsPauter Machine rodsbored and honed .020 overhot tanked and cleaned upblock decked .004ish (needed a fresh surface there)cleaned again and re-assembled to OEM specs with all new bolts and gaskets.

Cylinder head:cleaned uphand port and polished slightly on the exhaust side by me, we'll see how that one works out...new timing chain kit

Performance parts:T3/T04E turbo 50 trim compressor, .63 a/r turbine stage 3 wheel (whatever the heck stage 3 is it's pretty standard)Import-Autoperformance.com exhaust manifold with deltagateEbay Intercooler with I think 21x8x3 core.

Fuel:JWT ecu72# hr. injectors (the "75#" delphi injectors from http://www.racetronix.com)JGY Customs fuel rail with aeromotive FPRWalbro 255lph HP fuel pump

That's all the stuff that I've bought paid for and have in my hands...I'm still working out the IC piping and cant decide between a pre-made drop in set or putting together my own. The exhaust will probably be a full 3 inch turbo back with two dynomax straight through mufflers. If I've forgotten anything or you have any questions let me know It should all go together and get running over Christmas with luck.

As for making 350hp, it's been done with 15psi, you have to remember that 10hp per psi is a very general rule and sometimes it works out...sometimes it doesnt. I know someone who has hit 22psi on a stock block...but only once and only because he could afford a blown engine, there are people daily driving 15psi on stock blocks though

[Imissmyturbo]

If 300-350 is you goal the fist thing I would do is get a good standalone. I recomend a Speed density, Map sensor vs MAF. Most standalones out there run that way anyways. If you motor is good on the compression test you should have to do any internal upgrades. Spend the money on a good fuel system, turbo, manifold, intercooler. With proper tuning you should hit your goal.

[Nathan]

Standalones are nice but not only do you have the initial purchase price but also the cost of tuning. Then they still aren't as reliable if you tune them on the ragged edge, you'll have to tune them conservatively at which point you could have just plugged in a 500 dollar JWT ecu and be done with it.

[WDRacing]

No need for a standalone for 350hp...I'll get back with ya on the stock internal thing, need to get to work.

WD

[Nathan]

Ah, I should have said something more about standalones there...they are very good if you plan to do hardcore racing because you can make more power ultimately since you can run them more on the brink of detonation to make the most power, you can also change parameters at any time. I think a standalone would be great to have for a drag only car or a car making huge amounts of power such as >500hp. Most of my comments are in reference to street vehicles when I think that simpler is better if it achieves your goals.