fpscolin

1993 1.6L running MS2PNP, gt2560 @16psi, 420cc injectors. BEGI manifold, FM downpipe and 2.5" straight pipe exhaust
Made 180whp/wtq on a Dynapack

As far as I can tell, the engine is happy. Doesn't cough oil and runs smooth (although I haven't gotten around to doing a compression test). AFRs are on point. Why are my numbers so low, when similar setups have been pushing 225+ with less boost?

I've attached my tune as well as a picture of my timing table.

18psi

iTrader: (76)

what's "on point" mean? post a log

fpscolin

On point, meaning they tend to be exactly what the AFR table is set to.


Adding the log I have saved from before storing the car, hope it's indicative of something

fpscolin

Log here

18psi

iTrader: (76)

gotcha. well you're certainly running plenty of spark advance

fpscolin

Which (if I understand correctly) makes it even more puzzling - a relatively aggressive timing table should bump up power figures, right?

concealer404

iTrader: (3)

What is that in Mustang Dyno numbers?

ryansmoneypit

iTrader: (6)

compression and leakdown numbers.. need those. those numbers definitely suck IMO.

Altitude of test station?

fpscolin

Pretty much sea level, humidity was ~80%, temperature ~80*F on dyno day

Godless Commie

iTrader: (2)

• Is your clutch slipping?
• What is your exhaust diameter at its narrowest section?
• Do you have a catalytic converter?
• What gear was the car in on the dyno, and what gear did the operator enter in the computer?
• Is your timing belt installed correctly, with no teeth skipped?
• Do you have stock diff ratio, and was it entered correctly?
• Do you have odd sized tires/rims?
• Have you checked your intake tract (including TB) for obstructions?
• Have you absolutely made sure you have calibrated your timing using a timing gun?

18psi

iTrader: (76)

Dyno plot is not loading for me............

3.50

heartbreaker bro. heartbreaker

fpscolin

• Is your clutch slipping? No.
• What is your exhaust diameter at its narrowest section? At least 2"
• Do you have a catalytic converter? No.
• What gear was the car in on the dyno, and what gear did the operator enter in the computer? 4th.
• Is your timing belt installed correctly, with no teeth skipped? Bought the car with the timing belt redone ~20k miles ago
• Do you have stock diff ratio, and was it entered correctly? Not sure what he entered, but stock open diff.
• Do you have odd sized tires/rims? Dynapack's bolt directly to the hubs.
• Have you checked your intake tract (including TB) for obstructions? Cleaned the throttle body butterfly when installing my VTPS.
• Have you absolutely made sure you have calibrated your timing using a timing gun? Yes.

fpscolin

Sorry, not sure what this is? I have the log open in Megalog Viewer but don't know where to look for it.

BTW the log is NOT from the dyno session, but a drive I went on a month or so after it was tuned.

Godless Commie

iTrader: (2)

Well, you can always lie and say it made 280.

fpscolin

Sadly I already do and say it made an even 200. Cause... it definitely feels like it does. I've got no problem keeping up with my friend's F20 swapped NA; we're almost perfectly matched for power, I can pull on him past 75MPH...

18psi

iTrader: (76)

the dyno plot is the sheet or screen print they give you at the dyno session

2" is a very restrictive exhaust

fpscolin

The exhaust is 2.5", but since the Flyin Miata turbine elbow doesn't list its diameter I'd guess it to be close to 2". Maybe I'll try disconnecting everything at the DP and see if she rips

Here's the dyno graph

codrus

The FM turbine elbow is the same diameter as a GT2560 turbo at the inlet (which is around 2", but it's not a circle) and is 2.5" at the outlet.

Do you have a real Garrett turbo, or an ebay/china "2560" ?

--Ian

fpscolin

Bought it off of the Zilvia forums, so it's the Nissan variety.

codrus

So it's a Nissan OEM part?

Have you checked it for shaft play and wheel damage?

--Ian
​​​​​​​