I just finished putting my d16z6 together in my HF CRX and I have the car running on the basemap. So far I hae tuned that car in vacuum and it runs fine. It even runs fine in boost @WOT but one thing that I’m not sure about is the timing values in high cam. Are they too high? I never ran that much timing in some of my other setups, but they had alot more compression. The car runs at 12.0~12.2 in boost and the plugs look fine. Basically I wanted to know how much timing do you guys run around 15-18 psi in boost. Also I’m attaching my tune you you can take a look at the values. Any help would be appreciated. I’m running crome as my tuning program btw
The setup is:
- d16Z6
- TT rods/vitara pistons
- comp 59300 cam
- comp springs/retainers
- mild port/polish on th head
- stock intake
- 660cc injectors
- cdm cast manifold
- cdm .63/.50 turbo
- 2.5 downpipe and straight exhaust

1. Vitara’s are super low compression…so you are generally going to need more timing (depending) or be able to get away with a lot more timing in boost. The only way to truly tell of course is to get it on a dyno…
2. 1) Timing values change setup to setup for the following reasons:
   - cam timing
   - pressure/heat; high boost on a small turbo doesn’t create a lot of power but it does create more heat. Hotter combustion chambers burn faster, so they like less timing. Lower CR engines don’t heat the charge as much during the compression stroke, so they sometimes like more timing.
   - power; power creates heat, too, but when comparing really efficient setups timing “tends to” be more in line with power level. “Tends to” doesn’t mean always, so keep your eyes peeled.

   2) The manner in which timing is handled via various flavors of Honda ROM editors varies wildly. I’m going to post some eCtune screenshots, I would expect Neptune to be similar. Everything else is a dice roll, so use at your own risk *especially* if using an older version of Crome/Hondata without ignition corrections disabled.

   3) Insert some random witticism here.

   2G DSM T25 on a TT/Vitara Z6…. the cam was correctly timed by centering the distributor and adjusting the cam gear until the ignition timing lined up at 16 degrees. Be aware that:

   - Going off a stock cam gear if your head/deck has been milled or headgasket thickness is not OEM, or if you are running a non-OEM combination of block/head, will NOT put your engine in correct time.
   - Going off the timing marks on aftermarket adjustable cam gears = fail. They are marked 0 degrees, some of the gears on the market aren’t correct.
   - If you have D16Y just give up, this won’t work for you. Go directly to the dyno and play with cam gear settings to bias your power where you want it.

3. Oh yeah, reading plugs sometimes doesn’t mean shit. Shine a light into the spark plug hole, look for super tiny bits of carbon blasted off the tops of the piston. It’ll look like someone poked a pin through the carbon trail on the piston crown, you’ll see shiny glints of aluminum underneath. You need a dyno, or five times as much time at the track, to get everything out of your setup… but you can get 85% without a dyno, and if your compressor is big enough you can turn up the boost for more power without worrying about using it efficiently.

ok so ive been reading up on all this piston hype……and how some say its only better due to the low ass c/r, which seems true but the metalurgy seems much better also……anyways what would i be lookin at as far as c/r with an a6 block and y8 head with stock hg? from the d series compression calculator i used an a6/y8 combo yeilds around 10.8….and it seems that the pistons drop the c/r around a full point so would we be talking 9.6-9.9? that seems much more useable for turbo to me than the 8.0 c/r im seeing people have with those pistons in other d-series setups…….i may be talkin out my ass but a decent c/r with stronger pistons sounds good….

There seems to be quite a bit of disagreement on which way vitara pistons should be faced.
After reading this post I decided to do some searching and this is what I came up with.
Vitara pistons should face the flywheel in a Honda motor, because the motors have the timing belt on the opposite side.
Which means if both motors where sitting next to each other with the exhaust side facing you.
VITARA T belt <– left
Honda T belt –> right

1. The pistons will work both ways this is proven, but I believe this is the correct way to install the piston for maximum performance. If anyone has any Info as to why they think I’m wrong please do not hesitate to make your case known. Post factual information, Not the usual well this is what my local autozone guy told me.
2. I put mine in with the arrows facing the timing belt. It rattles pretty loud around 2k with a light load. If I build another one I will put the arrows facing the flywheel…

I wanna know how much money i would need to spend to turbo my d16z6 sohc vtec motor? including pistons, intake manifold, fuel rail, and injectors, and what else is necessary

1. Depends on how much power you’re looking for. You could go all out and get some CP pistons & Eagle or SCAT rods, or you could go cheap and go with aftermarket YCP Vitara pistons (they are made out of different material than the stock Suzuki Vitara pistons) & TunerToys rods. So you could spend $830-850 for stuff that will handle 600+whp or you could spend $400 for stuff that will handle up to 400whp. For an intake manifold, again it depends on your power goals. You could go with the Skunk2 Racing one or you could go with the cheaper Blox Racing one.
2. It depends if you are going to buy a turbo kit or if you are going to make your own..then for the pistons manifold and such it also depends how much u are willing to spend.