1.6L w/ GT2560R + E85
 

I'd like to thank this forum and all the users on it. Been super useful and I've gained a tremendous amount of knowledge! I know the 1.6 isn't the preferred motor on this forum but it's been a great learning experience, and this was my first time tearing down an engine and rebuilding it.

Car:
'92 1.6L
FM DIY kit w/ hybrid 2.5" - 3" Exhaust
Braineack built MS3X
OEM-ish stock rebuild
Scat Rods w/ arp bolts
ACL bearings
Toyota COPS
Flow force injectors 700CC @ 4Bar
5xracing AFPR
DW200 fuel pump
EBC

The tuner said the FM hi-flow cat is the bottleneck and is hurting my spool up, and a test pipe would help a lot. Thoughts?

Attachment 231802

Obligatory potato quality video:

'Grats, looks like some healthy numbers. How much boost?

I'm not sure how much it would help spool-up, but likely would free up some top end power and keep the car from nosing over after 6

The spoolup is never going to be good on a 1.6

Thanks! It's at 15psi with the stock 7psi internal wastegate.

I guess the only way to gain quicker spool is to swap a 1.8, which I'm planning on doing later down the road lol.

Nice job dude.

Looks like it would be a blast to drive.

You could be spooling around 1K sooner if you ask me. What are you using to get to 15 psi, EBC?

https://www.miataturbo.net/dynos-tim...attempt-87880/


nvm, I'm dumb. Carry on

Well I'm kind of interested. Tell me how.

Deezums thought it was a 2554 at first, not a 2560. That is why he thought it could spool quicker.

Using the mac 3-port solenoid.

From the tuner.

'91 Stock motor w/ 2560r running flex fuel sensor. Blue is 91 and red is e85

https://www.miataturbo.net/attachmen...ine=1466719770

Looks like I'm ~15 ft-lb less @ 3k and a lot worst throughout the rpm range lol. The only difference is (exhaust wise) is a test pipe.

Also, do you guys generally run catless? I was catless when I had my wrx and I couldn't stand the fumes.

Nice numbers, 'grats on your first engine rebuild. The dynojet will bring out the worst in boost threshold since it doesn't load the engine as much as real-world. I'm running a GT2554R with the same FM manifold exhaust as you and the boost threshold is realistically about 500 RPM sooner. A test pipe might help a little, but not "a lot". VVT would help a lot. Twin-scroll would help a lot. Neither of those are realistic options for us though.

Take a look at your timing map; you might be giving up spool that way. You also don't want your AFR's overly rich below the boost threshold; you want to use the higher EGT's to help spool the turbo.

Your numbers look good and the curves are nice and smooth. I love E85. I disagree with your tuner, the cat is not hurting spool up. A restriction in the exhaust will show up at high RPM as the torque falling off, not long spool up time. Your torque is holding pretty steady. However, something is slowing spool up. I have only dynoed five 1.6L engines with GT2560s on them and only two at 15psi or above. Both of those engines passed 200ftlbs between 3800 and 4200rpm. On all my dyno runs the engines are making at least 140ftlbs at 3000RPM.

What is you altitude? Setups like yours take forever to spool up above 3000ft.
What does the ignition map look like in the 3500 to 3500 RPM?
Are the EBC settings keeping the wastegate closed as long as possible to spool up the turbo?

I'm at sea level and here is the ignition map:

https://www.miataturbo.net/attachmen...ine=1466994048

I'm not sure if the ebc is holding the wastegate closed as long as possible. How would log that?

it should already be in your log. boost duty vs map
that's a pretty aggressive map. I like :)

Thanks, 18psi! I'll post a log/screen cap when I get a chance to do a pull.

I know this is kind of an older thread, but I'd like to take a look at your logs for comparison to my similar setup.

Totally forgot to post up the logs. I'll have to rummage through my computer for it when I get off work.