Just wanted to share a friendly run I did with a friend, comparing our tunes. This is my second ECU tune, went from Weistec to OE, but I'm seriously considering a retune by HD after this. My car made 462whp/422 tq peak on the dyno, and his is making about 20 more on same dyno. Mods are listed in the video. I'd love to hear any experiences you guys have had with HD.

Edit: Mods listed below
Silver C63(lead car): P31 package, ROW airbox, AFE filters, Benzworks headers, 2nd cat delete, HD tuning custom dyno tune, 100 oct., Hoosier drag slicks.
Black C63 (camera car): ROW airbox, OEM filters, Benzworks headers, OE tuning stage 2 tune, 91 oct., Nitto NT555 drag radials.



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You got walked! I would run pro drys and cut out the second cats and run 100 oct and load up the race map oetuning gave you.

Love HD. The pops are insane and the power gains are the real deal. I'd prefer to keep them a secret but perhaps it's too late !

Is HD a canned tune, or is it a custom Dyno tune.
You can't beat a custom tune

The way your friend "walked you" is definitely more than just "20" horsepower...

I have seen the graphs they have. 20 is peak hp difference. in the midrange HD is making 40+ whp difference IIRC. again, that's not exact but what I think I remember. regardless, it was pretty healthy.

I didn't get the handheld, just a flash tune so no race map, unfortunately. Updated the OP with list of mods.

I've heard nothing but good things about HD! Thanks for your input.

You're right, the HD tune is a dyno tune, his car is really dialed in.

Graphs show 20 peak whp, but midrange and down low consistently making huge gains. I've updated the OP with list of mods. Weird thing is we were dead even from a dig.

You nailed it, it's the consistent hp and tq difference throughout the entire range. Going to install filters and run 100 oct and see if there's a difference.

20 more whp 91 oct vs. 100 oct?

Also, would like to see both cars running the same octane to see where they compare. OP if you don't have a 100 oct. map from OE then don't waste your time because it's not going to do much unless you are tuned for it.

A custom tune will always be better than a canned if the tuner knows what he/she is doing.

I'm not so sure about the secondary cat delete actually adding any power. I did a before and after secondary cat delete dyno and didn't see any gains. Purely sound.

I agree. Plus HD tuning is the sh*t hahah

They have both the flash tune and a custom dyno tune. 10-20 whp difference of gains depending on how healthy your car is and relative mods.

I don't think there are any gains with 2nd cat delete.
I did mine, and didn't feel or see a difference in dyno results or trap speeds.

I definitely think you need to run the correct fuel, as well as tune your car for it and run again.
Compare apples with apples.

...and in reference to this above(no flame Skratch)

i run the aFe pro dry filters with charcoal removed like most everyone else
....BUT....
when BIP was tuning my car on the dyno previously the shop owner stated that the ROW boxes did indeed matter but that the filters made zero difference whatsoever....next time i went by i actually took my OE paper filters with me and sure enough when i ran it back to back they were within 2hp of each other(and that was with the aFe filters in on 1st pull so 2nd pull with paper had more heat soak). A really dialed in tune does make a huge difference but im going to have to give most of this credit to the octane difference as well.

And are you guys really running 91oct???? i have never run less than 93 in mine but then again most suppliers where i live only have 87,89,93

I have taken my car to the dyno 4 separate times and every time the car made the most power on the second and third pull.

same at the track. The second and third run would be the best runs.

all the oils get hot and thin and the ECU adapts and gives it all got.

may be geographical then as my car is never cool when i get to the dyno....the nearest one to me that i use is 170mi so when i get there the fluids are already plenty hot, loose and all "fluidy". Given these circumstances my 1st pull has always been my strongest(unless of course we tuned after 1st pull). But either way 2whp variable from pull to pull i am almost certain would qualify as acceptable differential. Pro drys in mine and they will stay but what they told then showed me was that i wasted my money.

man that is cRaZy!!!!! there are stations here that sell everything from 87 to 104 and as far as emissions are concerned i could literally run on baby seal blood and stripper glitter and no one would ever even know, much less say anything.

I would love to see the backfire/pops from that mix of awesomeness.

VERY closely resembles the phenomena when unicorns and clowns orgasm simultaneously.....it really is quite magical

the exhaust would smell like single moms and broken dreams.

I TOTALLY support single moms!!!!

LOL!

Yeah, Cali sucks for a lot of things, but there is 100oct available at some pumps, for $9-10 per gallon.
Can mix in a few gallons with the 91oct to achieve 93oct or higher, depending on preference.