sonofthehill

iTrader: (1)

Oh well, at least nothing broke.

phil21191

Yea thats always an upside,although I did manage my best 60ft of 2.02

DNMakinson

iTrader: (3)

Yep, better launch. Good deal.

phil21191

Another good day/bad day deal at the drag strip, wind speed/direction seems to have a big effect on my ET and MPH, at least I know its not a problem with the car because a couple of buddies are losing 4-5mph and at couple of tenths too.

Cut my first 1.9 60ft though

Left lane for me

sonofthehill

iTrader: (1)

My car was never the same after I trapped 110. That being said, headwind does affect our tiny cars a ton, more than the v8 boys. Almost always a good headwind at my local track.
Congrats on getting under 2 second 60'.

DNMakinson

iTrader: (3)

Impressive. So close to 12's.
What is your launch method?
What does boost profile look like?

hi_im_sean

iTrader: (3)

I'm going to run mine at the strip this winter on the vlad mega tune to see what I can trap, but I'm running a 1.6. Vald you think I can break 110mph? This has me curious and excited, and half hard.

Glad to see more td04 13ts around as there was only 2 others (that I could find on forums) besides dnmakison and I when I started my build.

DNMakinson

iTrader: (3)

I think Karter74 is going to install his old set-up in a new car.

They are more popular on MX5's in Europe and Australia, apparently.

18psi

iTrader: (76)

I doubt it, but of course it doesn't hurt to have goals. I was honestly surprised to see 111mph, and think it's going to be hard to even repeat, much less beat, even with OP's 1.8 setup.

phil21191

Just about every "budget" built turbo MX5/Miata here uses a TD04. Manifolds are more common and turbos are cheap used from WRXs

Boost targets look like this


This is the slip from my 12.9 earlier in the year. Notice the 14mph tail wind compared to this weekends 10mph headwind



I'm back at the dyno from my OP in November too.

Car is on Yokohoma AD08R which I run at 16psi at the strip. On board footage below



Edit: a tenth faster upto the 1/8 mile this weekend but a tenth slower by the 1/4 than my 12.9 pass

phil21191

Think I've possibly figured out why I haven't been able make another pass in the 12s. I've noticed I've got a slightly seized rear caliper.

But is that sticky caliper enough for me to lose 3 tenths (0.15s faster by at the 330ft, 0.06s faster at the 1/8 but 0.15s slower at the 1/4)

18psi

iTrader: (76)

don't think so. if it was slowing you down it would do it always

phil21191

I'm completely stumped then.

More power, AFRs haven't moved, boost holds solid, shifting at the same RPM. I just don't seem to carry the time for the second half of the track

18psi

iTrader: (76)

Unless you catch another tailwind...

phil21191

Well this may go someway towards explaining my "slow" 1/4 miles now. Was expecting at least 280hp on this particular dyno



Not yet looked into the root cause yet but I'm suspecting head gasket as it was cruising between 5-10 Celsius hotter than normal. Wideband was going nuts too, very bouncy readings quite frequently flicking from 13:0 to 17:0 with no lean/rich stumbles you'd expect with it doing that.

Whipple SC mustang was a bit of a shoe once they managed to get it to run without trying to blow the tyres off

18psi

iTrader: (76)

You probably bent a rod or two

phil21191

​​​​​I'm expecting to find a couple. Going to do a compression test and crudely measure rod lengths through the spark plug holes in the week.

Couldnt hear any usual noises through my Det cans on the dyno though

18psi

iTrader: (76)

det is one thing. bending them from sheer cyl pressure is another, and won't show any signs of det, probably cause there isn't any. you simply might be exceeding their capacity

been there, done that, got the bent rods to show for it

phil21191

Logic was you'd hear something due to the odd side loading on the pistons or some sort of imbalance to the difference in interia

phil21191

Can almost hear them bend when comparing the 1st and 2nd dyno pulls, should have had them overlaid really