Starting my KA-T project. Have lots of questions.

[slickster1013]

OK, so these are my plans and goals. I'm looking to get around 350whp out of my set up. I am doing a total rebuild to my motor. New pistons, cams, rods, valves, springs, fidanza flywheel, under drive pulley, beefy clutch, bigger injectors, JWT ECU and so on.

Now, I bought the CP pistons, they are 9:1 compression pistons. So my question is, with my compression being higher than normal turbo motors are, what is the most boost i can run safely and reliably with this compression.

Also, i'm not too educated on turbos yet, but i'm learning. But if anyone knows of a good kit i could buy, that will go good with everything i'm doing, and with my compression, PLEASE let me know. But i've been looking at this kit....http://www.jgstools.com/turbo/index2.html please let me know if i can go this route, or if another kit would be better.

Also, i planned on getting the V2 cams, but thought about getting the V3's. But someone told me I would have problems keeping it at idle, with the fidanza flywheel and all. Just wondering about that too. Sorry for all the questions, i know i seem like a noob, and i am to the turbo, but if you guys could just help me out here i'd really appreciate it. Thanks for looking!

[fiznat]

If you are still at the parts stage, I would consider getting rid of those pistons and just going with the standard turbo compression of 8.5:1.

There is a reason why most of use that compression, and a reason why we are all so worried about detonation. Your power goals are lower than what many would shoot for with the kind of build you're talking about - and that can be a good thing - but I would really reccomend against getting a higher compression piston because it will always be something you will have to work around. A well built motor (like you are listing) with a well matched turbo and a good tune will hit 350 rwhp EASY, and do it safely. Stick with 8.5:1, it wont ever cause you a problem.

The kit you buy will have a lot to do with how much you have to spend. (Suprise!) The JGS kit is a decent kit IMO with fairly well made parts for a good price. You can of course spend more and get more, and you could always spend less and get less. It depends what you've got in your pockets, really.

Cant really comment on V2 vs. V3 cams, although I do doubt that the V3s are so lopey that you'll have trouble idling. Still, someone with more cam experience should answer that question.

Good luck with your build! Keep us updated!

[Florida240sx]

People running stock ka's with 9.5 compression....JGS is a good kit. I'd personally piece one together if I did it all over. Save yourself cash.I got crower v2 cams. I like them. Crower v3 require upgraded springs etc. read about it on their site.If you got a good tune there is no limit to how much boost you can run. Ivan was running 43psi on the dyno with the engine..I have a built enigne with enthalpy ECU tune. t3/t4 turbo fmic and 3" exhaust. Running 17lbs. I'll have dyno in January once I get a Saturday off to get to the dyno.MAIN thing abotu Reliability is your tune. You can have the best parts in the market but with a ****ty tune it will blow up.

[slickster1013]

Awesome guys thanks alot for the feedback. So I should have went with the 8.5:1 pistons....i see, ok but i already bought the 9:1 CP pistons and they are in my kitchen right now lol. Anyone wanna buy some?

[slickster1013]

Ok so i'll probably go with the 8.5:1 pistons, but i want a turbo that i can turn the boost up on, and with minimal lag. Can anyone help me pick out a good kit. One that will go good with my set up and be reliable as a daily driver.

[Chezedik]

What brand and what type, how much can I save if I get them?

[slickster1013]

I bought them for $525 Brand new. They are CP pistons. 9:1 compression. They are.020 over. I'll sell them for $480 + shipping. Everything is brand new, rings still packaged and everything. I still have the spec sheet and everything. Let me know

[Reno]

People running stock ka's with 9.5 compression....JGS is a good kit. I'd personally piece one together if I did it all over. Save yourself cash.I got crower v2 cams. I like them. Crower v3 require upgraded springs etc. read about it on their site.If you got a good tune there is no limit to how much boost you can run. Ivan was running 43psi on the dyno with the engine..I have a built enigne with enthalpy ECU tune. t3/t4 turbo fmic and 3" exhaust. Running 17lbs. I'll have dyno in January once I get a Saturday off to get to the dyno.MAIN thing abotu Reliability is your tune. You can have the best parts in the market but with a ****ty tune it will blow up.

hey i may be interseted in how and what u put in..

[Zion8561]

Don't turbo grind cams (or any agressive aftermarket cams) lower the compression ratio a little anyway? Something to do with the extended period of intake/exhaust valve overlap time vs. the stock setup.

I am curious to know the extent that cams effect compression because I am looking to do a setup similar to this, and was considering 9:1 pistons.

I am sure 8.5:1 would be safer since this is my first F/I build also, but I do not want the motor to be a slug off boost.

Edit: Also, what are the advantages of going with oversized pistons? It seems like a waste unless you need to because your block needs to bored due to wear/damage. I guess you gain a little displacement, but at the cost of thinning (weakening) the block a little. Is it likely that a motor with 100k can just be honed during a rebuild?

[WDRacing]

The dur. increase is somthing that comes into effect when dealing with V8 compression, not so much at with the 4 valve DOHC motors. I suppose if you're running 300* Dur cams then you may have issues. But not even Ivan who runs low 9s uses cams like that.

Persoanlly, I wouldn't go under 9:1 CR pistons. If you want more boost for the track, then use race gas or run a decent alcohol injection kit. The more efficient the motor makes power off boost the better it will perform on boost. With proper ignition and fuel tuning a 9.5:1 CR motor is fine for boost. I ran mine on all stcok parts at that compression with 14psi and 20 psi boost settings, no detonation at all. I did toss a rod, but that had nothing to do with compression.

WD

[Chezedik]

The cams CAN play a part in dynamic compression, but this should not be thought of as a way to lower static compression in ANY WAY.

The longer duration cams that are offered simply change the rpm range in which the engine is most volumetrically efficient. This will make it show lower numbers on a compression test, because it is pushing this range into the higher RPMs, and so there is less air to compress in the range in which the test would be performed, which would make one think they had lower compression, but static compression remains unchanged. Instead, you will simply find that you will have higher dynamic compression at higher RPMs, which is why you end up making power in high RPM ranges v. lower RPM ranges with aftermarket cams. This is not a fix for static compression, it is only a way of making sure that you get more air/fuel when you need it. The only exception to this will be adjusting cam timing to increase overlap. But this is an even worse way of lowering compression as you are just increasing emissions and fuel consumption, and lowering power across the band.

Stick with the 9:1's, believe me. Unless this is a dedicated track machine, or you fancy yourself one hell of a tuner, you will not find significant gains in lowering compression. I have 8.6:1 (from a .120" Cometic gasket), if I could, I would be at 9:1, instead, I have to run increased timing and boost to make better torque.

If you are ready to have to do this then knock yourself out, but if you are street driving, then I would just go 9:1, and then run higher octane fuel at the track. You will get better low end torque, better economy, and an overall better feel. Not to mention, you will still be able to run boost levels that are more than adequate.

WD, BTW when you tossed your rod, did it bend, break (on the rod) or toss off the cap?

[WDRacing]

I haven't broken down the motor to find out. I think I may had run into lubrication issues/oil pressure issues causeing a bearing to spin.

WD

[Chezedik]

Yeah, just wondering because I put in those ARP rod bolts, since the rod I threw was due to spinning a bearing and then breaking the bolt off. Thinking if I can keep the bearing cap in place that the rod is good for 400+ hp, as Cory is showing us.

[slickster1013]

Thanks for all the comments on this guys, i've been trying to get these answers for awhile. I think i'm going to stick with the 9:1 pistons, and just get the V2 cams(264's). But, i'm still looking for a good turbo kit to get too. Like i posted earlier, I was looking at the JGS Precision turbo kit. But if anyone knows of a better kit, that comes with a little bit more stuff, let me know. Thanks alot guys for all the help

[Chezedik]

Build your own kit, you can save some money, and you don't have to worry about the things you didn't like about someone else's kit. On the other hand, you have to make your own pipes. If you have a welder and a reciprocating saw, you are good though.

[Chaotic_Warlord]

I plan to run the same spec pistons and cam setup. As far as turbo kits go it depends on your budget, if you want a full kit and have the money Id suggest the Turbonetics kit or even the Greddy kit.

[slickster1013]

Oh sweet your going with the same set up? That's cool, when do you think yours will be done? Mine probably wont be done til around june, well that's my goal anyway. Maybe you could help me find my turbo and other stuff. As far as my budget goes, it doesn't matter, because i'm not going to go cheap on anything i do, if i have to save up for it, i will. I just want the best quality parts, because i want it to be reliable, because this car will be my daily driver, and track car on the weekends.

Where can I find the turbonetics kit? Or the greddy kit...what websites or sponsors carry them?

[Chezedik]

Turbo-kits.com, but the Greddy kit is not for the S13, also it does not come with an intercooler. The turbonetics is available and is a pretty good kit, but pricey. I like that it has an available ball bearing option.

But the IAP kit and N-Sport kits, are the only ones that I am aware of that feature a kit for S13.

[Chaotic_Warlord]

turbo240.com has a kit for the S13 don't they, since it's owned buy Ivan you can be assured that all the parts they sell are good quality, but they are a little pricey, hell they even sell built blocks in 2 trim levels, you just have to add your own turbo kit.

[slickster1013]

I don't want to buy a built block, i want to build it myself. I'll appreciate it more that way. But thanks again for the help guys

[halnfl]

you should get the manifold and dp from jgstools, then get a precision gt32, and ebay fmic, 750 injectors, fuel pump, and an enthalpy tune with your built engien and you'll be golden. 9:1 is definetly suitable for what your looking for, it'll give you better out of boost drivabilty(not much but noticable). you could get the eagle rods since there dirt cheap, I have pauter myself but it was either those crower's or carillo's when I built my engine. You should sit down and figure out what kind of money you'd like to spend and add about 35% to whatever you come up with since its you dd. Or you could just get a beater car to dd, and just turbo what you have and have fun learning about how u can and can't blow it up.

[slickster1013]

i'm still deciding whether i should peice together my own kit, or just save the money and buy a kit that comes with everything......

[Chezedik]

I have a Z32 MAF I am selling, would you be interested?

[slickster1013]

why yes i would be interested. Got any pics? What condition it's in.....how much your lookin to get. Let me know. Thanks

[Chezedik]

Sorry, it's already sold.

[slickster1013]

well thanks alot