sonofthehill

iTrader: (1)

A better pic of the small and large turbo comparison.
Small turbo(blue) made 218 ft/lbs at 3400 and 230 HP at 6200.
Larger turbo(red) made 212 ft/lbs at 4300 and 238 HP at 6200.
I suspect that I was a couple kpa higher with the larger turbo but I need to check my log to be sure.<br >

18psi

iTrader: (76)

so basically at this pressure level, the bigger turbo gives up a lot and gains little

although looking at the afr graph you did help the smaller turbo out a little bit

turbofan

iTrader: (1)

Wow

that looks like a 1.6 vs 1.8 dyno graph

sonofthehill

iTrader: (1)

I don't think their wideband works too well at higher afr's as I was hitting my target fairly well. I must admit I don't tune for 11.8 right at 100kpa, closer to 12.8 tapering to 11.8 as I approach 140 kpa or so, trying to have decent mileage.

shuiend

iTrader: (24)

I am curious how the larger turbo would do if you cranked up the boost to closer to 20psi. Not suggesting you do it on a stock motor, but that could possibly be where it hits its efficiency point and start making better power.

sonofthehill

iTrader: (1)

I have been working on a set of 8.8:1 pistons, which I plan to mate with a set of manly rods, for my block from Vlad.
But no real time frame yet.

18psi

iTrader: (76)

it should definitely wake up, my 3076 definitely did after 15psi. but even still, that's more for highway pulls and not much else.

and they die REAL quick past 20psi. like, weeks

I love the back-to-back comparisons btw

sonofthehill

iTrader: (1)

I will say this, I had it tapering up to about 16.5 psi or so at the drag. I got a terrible time and thought I broke something in my driveline, turned out I was spinning my tires in 2nd and 3rd.

sonofthehill

iTrader: (1)

Here is a comparative log for the T3 48/60 today with the T3 48/42 in the background from last time.



Here is my extrapolated rpm axis on the dyno readout.

sonofthehill

iTrader: (1)

It was about 10 degrees warmer this morning but I had a few extra kpa too. Basically they perform the same above 4300 rpm in the 15 psi range but the smaller one reaches 15 psi much sooner.

sonofthehill

iTrader: (1)

At one point the dyno operator looked at the odometer and asked if there was really 237,000 miles on my car. I said, "yeah, and this is the original motor!" The look on his face was priceless.

sonofthehill

iTrader: (1)

Yeah buddy
102, 103, 104... It was pretty hot today, on crap CA 91 gas as usual.
13 second Miatas definitely get noticed around here, they gave me a hard time about running under 13.5 last time but said if I bolted my hardtop back on it would be considered a hardtop, not a convertible. I just mellowed my launch a bit for now.
The last time slip was against one of the 2015 mustang gt's, but I think it was on all season tires like me. It didn't seem to be set up nearly as well as Vlad's car. I actually almost beat him and was quicker to 330', it was a great race, neck and neck the whole time.

18psi

iTrader: (76)

NICE! that's great man, car is moving.

sonofthehill

iTrader: (1)

Thanks man! Couldn't have done it this reliably without everyone's input.
I think most of the improvement is from shifting at the right point.
Also helps when you have a badass mustang next to you that you somehow managed to get ahead of in the first couple hundred feet.

shuiend

iTrader: (24)

I am going to need you to turn up the boost a bit and beat that 1.6 that just went to the drag strip.

18psi

iTrader: (76)

I think it will be hard to beat that car since that's basically the ragged edge of keeping the engine intact

sonofthehill

iTrader: (1)

No problem Lars!

I don't think there is a private event next week so the drags should be on.
Hopefully my wife will let me put the top back on.

shuiend

iTrader: (24)

If Carlos does not live his life 12 seconds at a time, I will be disappointed.

sonofthehill

iTrader: (1)

You don't think my all seasons will save me?

18psi

iTrader: (76)

spinning aint winning. so if they do save you, it will be by spinning and killing your time (but helping your trap speed).

and if they hop a lot, well, you're gonna break stuff real quick