MKTurbo kit on a grenade motor
 

So i've been driving my car around on Grenade Motor v.1.0 for a year and a half (BP4W dingle berry honed, ebay vvt pistons slammed in, head shaved .025). The car ran 9.1's @ 74.something in the 1/8th and around 150whp on bias ply slicks with the 6 speed and a 4.3 torsen. Seeing how luck was on my side for how poorly that engine was built I decided to tempt the fates again and build Grenade Motor v.2.0 with a turbo kit that is a blatant plagiarism of Sonofthehill. Please read my words with your sarcasm glasses on, I built this iteration in my driveway in 2 weeks to troll my friends who never finish their cars.

Grenade Motor v.2.0 specs:

• BP4W: China forged h beams, cheapest ebay 94-97 pistons with sealed power chromoly rings, clevite rod bearings, new OEM vvt oil pump. Still has .025 head shave. It's been dingle berried twice now. Nothing was measured. Crank has never been out of it in two 'rebuilds' now so the mains are... probably good. I wouldn't build a motor this way if it wasn't for comedy.
• Stock head with 94-97 valve springs. BP5A intake cam. Vics intake
• Nb1 6 speed, 949 racing 4 Puck sprung clutch, 3.9 torsen
• Turbokit: MKTurbo. I'm fairly certain i'm running the same turbo as Sonofthehill (.63a/r exhaust, .60a/r compressor with 3" inlet) ~218kpa
• ECU: Rev built MS2, non-sequential
• Fuel stuff: DW200 pump, FF640's, stock fpr, 93 pump gas

Set up has about 700 miles on it now. Made 285/225 tq this morning. We didn't use an ignition pick up on the dyno so the rpm's are a bit goofy (my rev limiter is 7400 but car makes peak hp at 7600 on graph). I'm seeing 17psi by ~4300rpm (will try to log soon to give spool data). Ran 2 12.9's last night @ 110. Be gentle on my timing map, I'm still learning!

https://cimg7.ibsrv.net/gimg/www.mia...1befc20e68.jpg
https://cimg8.ibsrv.net/gimg/www.mia...cbfd540b33.jpg
https://cimg0.ibsrv.net/gimg/www.mia...3e995acc47.jpg

Videos from last night:

Very nice, the best part is trolling your friends who never finish their cars :bowrofl:

I would suggest that you could achieve the same power with the .48a/r turbine housing and have it on by 35 or 3600 rpm. I might be willing to part with my smaller housing since I don't think I am going back.

The man himself! Would I have to swap exhaust wheels as well to run a .48 exhaust housing? Also, how far did you push your car on 91? 20 psi if memory serves?

If the turbo is the same one I am currently running, the exhaust housing is interchangeable. Although the .48 housing is a restriction and will take more boost to make the same power.
I think you are pretty close to the max, I have run more boost on 91, but I have nice forged slugs.

This is what I've got for reference:

https://www.ebay.com/itm/CXRacing-T3...item20ccf1da87

That is what I am currently running. It makes more power with less boost than the .48 housing, but comes on lazier, 4300 or so, like you said.

I honestly don't mind it. I celebrate the old school turbo powerband. It doesn't hit the tires as hard so this rig dead hooks from a roll (205/50-15 Federal 595 RS-RR). I dig it.

Me too, I still get 5psi or so instantly in top gear on the freeway, which is plenty.
:bigtu:

Took the car out to the 1/8th mile tonight on my new set of Mickey Thompson ET Street R's (225/50-15).

Cliff notes: Best pass: 7.72 @ 89.11 with a 1.66 60'. (Car should do 11.999999999999 1/4's at this point)

I'm pretty sure Lars should start offering this turdbo that Sonofthehill and I are running with his kit (And for sure call it MKUltra) for those that want 11sec miatas.

Timeslips. I'm car # 05. https://cimg1.ibsrv.net/gimg/www.mia...2cad65da43.jpg8.x passes trying to figure out how to launch the car
https://cimg2.ibsrv.net/gimg/www.mia...3e817dcfd9.jpgMy collection of 7.x passes

Good job! I am curious if those tires rub on anything at all?

I have been thinking about bending a couple of the hangers to eliminate my slight bump on hard launch, just haven't got around to it yet.

https://cimg9.ibsrv.net/gimg/www.mia...1fb3663c22.jpg
https://cimg0.ibsrv.net/gimg/www.mia...8561309da3.jpg
https://cimg1.ibsrv.net/gimg/www.mia...23d071a186.jpg
https://cimg2.ibsrv.net/gimg/www.mia...94a6272a21.jpg
It's a snug fit, but they fit with rolled fenders on 15x7 + 30 Kosei K1's. On 15x8 +25's that I originally test fit them on they rubbed the sidewalls on launches. I had the launch control set to 5800rpm and was basically leaving with a clutch dump and the exhaust wasn't hitting anything. Most of my hangers have hose clamps around them though to trap everything in place.

Your car would definitely do wonders with a sticky tire (you know it, I know it, everyone knows it lol).

Probably 1.5 or less 60' with wrinkle walls. Very nice work, especially on a grenade, haha!

Car broke cylinder #1 piston in half last December. Bores didn't get injured during the failure so I dingle honed it (for the 3rd time now) and slammed some stock bore CP forged pistons in. All other stuff is the same.

20psi and 6000rpm dialed up on the launch control. I'm worried about leaning on it too much harder on pump gas. Still, it's solidly an 11sec car at this point.

https://cimg4.ibsrv.net/gimg/www.mia...7b8733b3fe.jpg

Video of run:

Good job! I have been thinking about trying that turbo, can't wait to run again.

Do it! It goes right on, costs 230 or so bucks shipped. You put a sticky tire on your car yet? Or are you still sorting out transmission options?

Still sorting tranny options, might have something to try in the next few weeks. Until then I don't want to make any big changes, basically driving gently, my last 5 speed is still pretty quiet.

https://cimg4.ibsrv.net/gimg/www.mia...79941bf96d.jpg
https://cimg6.ibsrv.net/gimg/www.mia...4950db2af9.jpg
https://cimg7.ibsrv.net/gimg/www.mia...299d2cfb60.jpg
How is that torsen living through that wheel hop?? I had taken my 92 turbo car (made 220whp)to track once and third run the wheel hop split the torsen gears in half and stuck it through the case. Is yours braced?

Wheel hop doesn't happen on slicks. You should use slicks.

Thats wheel hop.

https://cimg8.ibsrv.net/gimg/www.mia...a4fedeb3cc.png

The diff housing is boxed in front and back. (I've broken a stock housing already).

In that video you referenced i'm on street tires (notice the wheels match front to rear). All other passes i've made since then have been on 225/50-15 M/T ET Streets. It doesn't hop on them, just dead hooks and goes which is equally unsettling whilst side stepping the clutch at 6000rpm.

Got ya!
Good stuff man!

Jesus dude. I just read this thread, I didn't see any mention of rods.. are they stock?

If so, it seems interesting that you went through some pistons before ever bending a rod. Seems contrary to popular belief, but maybe it's due to stock compression on 93 octane and if it held up long enough you'd eventually banana rods.

It's got some china forged rods in it from the v2.0 build from my first post in this thread. They carried over from the rods only build into v3.0 where I tossed forged pistons in.

Makes sense! Do you think you had any detonation to make the oem pistons let loose, or just power related?

I didn't see any signs of detonation. I couldn't be bothered to measure ring gaps when I put together the rods only motor. I suspect it butted rings together under boost as it broke around the circumference of the ring land and the whole skirt escaped. My guess is 95% assembly neglect and 5% ebay stock replacement piston weakness. I'm just shocked the rings were able to hold the skirt on so it didn't fubar the cylinder bores.

https://cimg4.ibsrv.net/gimg/www.mia...3a17d20e65.jpg
https://cimg6.ibsrv.net/gimg/www.mia...d2db54da23.jpg

Re-dyno'd today with the new forged piston'd engine. Changes since last dyno: Bigger billet wheeled ebay turbo, running 250kpa now, and the B series intake manifold on the miata head flange.

350whp/323wtq. The FF640's are basically tapped out at this point. It creeps to 11.9 - 12.0 as it pulls through the upper rpm's no matter how much fuel I command. I won't be running this much boost again, was just curious to see what it would make when it was set on party.

Wow those are great numbers man. Only downside is the turbo is crazy laggy judging by the Dyno graph and looks like the pull stopped at 6500rpm, I bet it would have made more power had it been revved out more. Still though congrats that's awesome!

Solid. You are the second person reporting 350whp on FlowForce 640. Definitely beyond the intended range, but so cool to see.
What type of Dyno is that?

Not sure what dyno it is. He was using an optical sensor on my crank pulley that I don't think we had adjusted perfectly. Pull ran until the rev limiter that I have set at 7400 so it probably doesn't make quite that much torque at the wheels.

Did you happen to take a log? I'm wondering what duty cycle you were at.

I didn't log anything that time, just noticed when I punted it on the street that it kept creeping up toward 12.0 in the higher rpms despite me asking it nicely for more fuels. I'm planning on going back to the track this Thursday, I'll make a mental note to log a pass and see what the DC is.

You should definitely log your drag racing if you can get away with it. Nigel has some bigger injectors that are working very well for me, might need the bigger pump tho.

Interesting, you guys race on Thursdays?

Yeah Thursdays and Fridays at the local 1/8th mile. The ZMax 1/4 mile track rarely has TnT.

I should hopefully be getting some videos tonight of this car at the drag strip.

would love to see it rippin'

I will hopefully get a video of Tehzack running a 7.68 in the 1/8th mile posted later today.

@tehzack , got any pics of how your WGA is mounted? This turbo seems to have some weird bolt spacing.