Gutted Header & Front Pipe - Dyno Inside

[rice_classic]

Another item missed in the article is the fuel type.

The Dynasty cars are SCCA T4 and won the Runoffs (because of Oscars penalty) and they didn't do it on 92 octane E10 pump gas. The article mentions 93 but competitive teams rarely share their secrets.

T4 rules state that one must run only the fuel type in the factory service manual.

The factory service manual says "unleaded" with '93 or higher' in parenthesis. So as long as it's unleaded that allows unleaded 100+ octane.



The other thing in the article that stood out is they say they have a Mustang Dyno - but then say usually cars with stock header and aftermarket exhaust see 185-190whp with a tune which seems like a high number on a Mustang Dyno? So to be at >200whp on a Mustang dyno with only a drop-in filter, gutted stock header and aftermarket exhaust is pretty damn crazy, especially if it really is on 93 octane.


I'm thinking I should call Circuit motorsports and buy that tune.

[86MLR]

Thread bump for more data

2017 86 ADM

Snorkel mod
OEM air filter
Mishimoto intake pipe (no resonators)
OEM header (punched out cat)
2.5" Ultrex overpipe ($90, LOL)
2.5" X Force mid pipe (cat punched out)
2.5" X Force resonated cat back (X Force is cheap, LOL)

Ecutek Racerom

98 RON

Before tune is with all bolt ons, cut offs and knock outs

Just on 198hp

Difference between pre and post tune is night and day

Tuner says he can lose the dip, BUT, for the cost, he and I don't think it's worth the outlay.

[FRSBRZGT86FAN]

Originally Posted by ApexEight

What's that guy's deal lol. Better change your final drive bro, he says you need to

Originally Posted by Lantanafrs2

Sheesh I'd rather swap a header than rear end gears

Originally Posted by nikitopo

If your rpm's are so low and you are in the correct gear, then you need to change your final drive ratio to a shorter one. Maybe a 4.55 will match good on such track. It always depends the track. It is not optimal to solve your issue by eliminating the torque dip. No matter how good is the curve in the mid rpm's, you won't get the maximum acceleration. You'll need to have the revs on the higher end area for the best acceleration.

Usually anytime I see 'nikitopo' chime in a thread it's usually baseless and not worth reading into....

[DarkSideFRS]

thread bump

how bad is the resonance in the cabin with the gutted cat?

[MRBRZ1]

Originally Posted by Joe-G

There's a whole separate discussion regarding gutting the factory front pipe and header... but I never came across an actual dyno showing the gains on an NA setup. So for those interested, here's some reference in case you guys want to do the same.

Baseline is from another local car, which has been used as a baseline for a bunch of the locals. I think its pretty close to what these cars make stock at our altitude.

Based on my logs, the car runs a little rich and the MAF sensor still needs to be re-scaled due to the GS intake. MAF scaling is untouched from the Stg 2 OFT 93 EL map. LTFTs are around 8%, and under WOT/High RPM I think AFRs are low 11s. Was at Castrol Raceway this weekend and the car was backfiring non-stop during each session.

Modifications:
- OFT OTS Stage 2 93 EL tune
- Gutted factory header
- Gutted factory front pipe
- Custom muffler delete
- Grimmspeed Intake
- NST lightweight pulleys (Crank, water pump, alternator)

thanks for sharing this information.

Should i digging the cat of header only or cat and frontpipe must?

For now i'm with miltek catback and inbox filter oft stage 1.
I checked and found that there is no more difference between uel and el header map for stage 2 in ver 4.03.

What is acceptable knock value and what should be the afr in case i will switch to stage 2 with modified header?