ICE-.-

why do you think the difference between a turbo 1.6 and a turbo 1.8 will be drastically different than the difference stock, which is only 20hp😥

borka

iTrader: (1)

It's not about the 20 hp difference, a 1.6 can be made to make Power, but it's about a satisfying Driving Experience in which the 1.8 provides much more lower and torque much quicker spool and more torque overall than the 1.6 which on the street makes for a much more pleasant turbo car driving

ICE-.-

Again, that's a good point but I thinking by using a kraken manifold and a 3" exhaust all the way much of the spool issue should be improved I think. And for the torque do lower compression Pistons not feel more tourqy on boost?

sixshooter

iTrader: (12)

It can be done.

Generally speaking a given engine will double its output if you double the atmosphere going into it. It then follows roughly that a 20 horsepower difference will be a 40 horsepower difference. Many would consider the difference between 200 horsepower and 240 horsepower to be noteworthy given a similar price and effort.

But yes, it is possible to turbocharge a 1.6.

It should be noted that most turbos will spool up several hundred RPM earlier on the 1.8 engine.

HmoobDude

I'll start off by saying I have no experience with the 1.6 or even a turbo 1.6. But from what everyone says and what I read is that it's more than just a 20 hp difference as Borka pointed out. I can't find the specific dyno picture (he has them overlaid in one picture) Shiuend likes to share in regards to his MKturbo set up, but here are some dyno plots (from MKturbo) comparing the MKturbo kit (I believe comparing stock for stock) on a 1.6 vs 1.8.





While peak power isn't much different and can be compared to the 20hp difference you mention. Just looking at the area under the curve for power and torque under 4k is where the difference truly lies for street driveability. While I know your plan is to build your 1.6 this maybe something to consider.

ICE-.-

honestly I think a few extra psi will make up the difference and I'm too far down the rabbit whole anyway to switch. With that said I think I will be able to make more than enough power to suit my earlier goals.
The only thing I really have left to decide is whether I go with a gt2560r or a gt2860. From my very basic understanding of turbo's the 2860 will give me higher hp and later spool and the 2560 will do the inverse. With that said what do you guys prefer?
I'm leaning on the side of the 2560 for the sake of street drivability and quicker spool, while still being able to get a 260-270whp number. Is this way out of the ballpark for this turbo on a 1.6?

cpierr03

It remains to be said that 1.6 vs 1.8 isn't just a difference in bore and stroke - head/manifold design has changed as well. These are factors change that 20hp difference when boost is introduced.

ICE-.-

again, its a good point and i'm not disagreeing however i think the 1.8 vs 1.6 discussion has been beaten to death, and in my case there is really no point to thinking about it because I have invested a few thousand in my engine already. That being said maybe while i'm enjoying my current build I will follow in the car passions channels foot steps and build a vvt engine, however for now I am completely set on my current path, thanks for the input tho!

sixshooter

iTrader: (12)

The 2560 is a better match for a 1.6 street car.

borka

iTrader: (1)

On a 1.6L
2560 will make power around 4k rpm
2860 closer to 5k rpm.

2560 is the wiser choice.

deduct 600 or so rpm with a vvt 1.8

ICE-.-

ok cool, i think you're right on the 2560 call, and with that good price I think its a no brainer, i'll order one tonight. In reference to the power this is likely to make is 240-260whp is range accurate with 8.8:1 pistons n 91 realistic?

borka

iTrader: (1)

im fairly sure you can make around ~260hp on a 2560r. with a 1.6L.

for reference, my 2560r at 17psi on a 1.8 vvt engine made 265hp. but my tune was pig rich around 10afr, so with proper fueling of 11.4, i think it would yield around 280hp.

SpartanSV

I just picked up a used 2560 and had looked at every dyno sheet I could find. I think that's the likely range you'll end up in.

ICE-.-

Thanks guys, I'm super stoked for this project and your input means a lot, stay tuned for a sick build!

ICE-.-

Alright, well just under a year later i have my 1990 miata running nicely with 400 miles on the new engine. Along the way I have realized a few critical things about such a build that I didn't take into account originally! first off I had no idea how stressful it is to start an engine built by ones self. Knowing that I put the piston rings definitely reduced my confidence that it wouldn't turn into metal shrapnel right off. When I first went to start the engine I had absolutely no luck. I couldn't seem to track down the issue, that is, until I realized the spark plug wires were out of order. Just in case anybody else this issue just make sure that the pistons that go up in pairs are on one coil pack, ie 1-4 3-2. As long as you do this seeing as the engine is batchfired it is sure to start.

After getting the car running I soon realized that heat management was indeed an issue, and that my gunk filled radiator wasn't going to cut it. Between a Front Mount Intercooler, and a turbo water line going directly into the mixing manifold(probably not the greatest idea ever) the car was hitting over 205 going up small hills, and if I accelerated at all would start to climb as well. My first step to remedy this was to flush the coolant, and seal any and all leaks I could find in the system, I then moved on to some ducting(i.e cardboard from under the front lip of the bumper to the front axel). The ducting actually had a fairly decent effect, but not nearly as much as getting both fans to turn on at a lower temperature. With the ms3pro pnp you can set up injector j to be the ac fan control super easily, its under programmable outputs. Well even with the combination of ducting and dual fans the car would get super hot up hills, but was not able to cruise at around 196-199. Compared with the 205-210 I was getting before I took this as a partial success, but still pulled the trigger on the miata compatible mishimoto radiator from FAB9Tuning. Let me just say, this thing seems to have had a bigger effect that all the other things combined.

With cooling out of the way I moved on to letting the car make actual power. During this whole period I was doing engine break in stuff, so bringing the engine up to about 4k rpm in 4th gear and then coasting back down to around 2k rpm. Apparently this process of exposing the cylinders to pressure and then vacuum allows the rings to seat better. I have also been using BR30 break in oil, I honestly have no idea if it is really all that special having no other data points but it gives me some peace of mind so I guess that's worth something.