JDL 4-2-1 EL header

[Goingnowherefast]

Great data 949. Kind of confirmed my suspicions. In 2021, considering the price hike and broken weld issues, there's not much reason to get the ACE350 over the JDL 4-2-1 IMO. Unless you're really looking for low end torque.

[jflogerzi]

Originally Posted by Goingnowherefast

Here's a vdyno (weights fixed, TY JBezugs).

Blue = Tomei UEL w/ ~4 tune revisions ~E77
Red = JDL 4-2-1 w/ 1 tune revisions ~E71





Man you sniped me RIGHT before I saw the issue while reviewing my post lolol. Weights fixed. Mine are also from a recent corner balancing sessions so they are accurate and adjusted for fuel. Could you delete the quoted vdyno so people don't get confused?

JDL really needs to be dialed in to extract all it's power.

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[Mike_ZN6]

Originally Posted by 949 Racing

Dynos of Blub. E85, Delicious tune, Perrin intake, custom 2.5" exhaust and 2.5" metal core cat on both headers.
OEM is 91 pump gas and 100% unmodified.
Ace350 had a torque bump between 3000-3500.
JDL had a bunch more power past 7100.
Both eliminated torque canyon of OEM.

We sold the Ace and run the JDL now. Testing Crawford BPB but so far no power area gain. We'll play with the tune a bit. If no power gains we'll remove the BPB.

This is exactly what many people on this forum have been waiting for!

[Mike_ZN6]

Looking at the dyno, the ACE does appear to have a 15 ft lbs difference around 3250 rpm. It is hard to tell exactly because some of the ACE's line is missing, but I would guess the ACE has an average of about 10 ft lbs over the JDL between 3200-4200 rpm.

For a track or auto-x car, this probably makes very little difference because you would almost never be down in that range of the power band. The increase in power past 7100 rpm is probably more valuable in that situation.

However, for a daily driver that is constantly launching from a standstill, the ACE torque advantage between 2300-4500 rpm may be a bit more crucial.

At least we have verified proof the ACE is a bit better down low and the JDL is a bit better up top.

[gpvecchi]

My 2 cents: JDL is better in upper range because the primaries are 45 mm (ACE 42.7), ACE is better at lower one because of longer secondaries.

[mistople]

FWIW my A350 had a flange weld failure too. Cracked right through. It's sitting in my shed collecting dust. I absolutely loved that header but the 4->2 connection coming apart multiple times on track and this weld issue left a sour taste in my mouth :/

Edit: Didn't mean to knock the company or product. It was the best thing I ever put on that car! Sounds like there is a fix so at least I can sell it at some point now that I no longer have the BRZ.

[Tatsu333]

Originally Posted by 949 Racing

Dynos of Blub. E85, Delicious tune, Perrin intake, custom 2.5" exhaust and 2.5" metal core cat on both headers.
OEM is 91 pump gas and 100% unmodified.
Ace350 had a torque bump between 3000-3500.
JDL had a bunch more power past 7100.
Both eliminated torque canyon of OEM.

We sold the Ace and run the JDL now. Testing Crawford BPB but so far no power area gain. We'll play with the tune a bit. If no power gains we'll remove the BPB.

What over pipe are you running with the JDL header?

[949 Racing]

Originally Posted by Tatsu333

What over pipe are you running with the JDL header?

JDLwith cat. I don't see it on their site now though.

[NicFromTheNorth]

This thread seems appropriate for posting dyno numbers I got at Light Touch Tuning. They provided .csv files of the data so I made this graph, rather than posting a screen capture of their software also showing runs we did with another tune.

car: BRZ 2016
mods: JDL 4-2-1, everything else is stock
tune: Wayne Rom v167 for ACE, 91 octane fuel

[StraightOuttaCanadaEh]

Originally Posted by NicFromTheNorth

This thread seems appropriate for posting dyno numbers I got at Light Touch Tuning. They provided .csv files of the data so I made this graph, rather than posting a screen capture of their software also showing runs we did with another tune.

car: BRZ 2016
mods: JDL 4-2-1, everything else is stock
tune: Wayne Rom v167 for ACE, 91 octane fuel

how do you like it? Thinking of installing it too, although I would be tuned on 94, would you recommend?

[NicFromTheNorth]

Originally Posted by StraightOuttaCanadaEh

how do you like it?

Overall I am satisfied, even though the dip at 3200 rpm bothers me a little because I can definitely feel it. I would recommend this header but I have never driven a UEL equipped BRZ so I don't know whether I'd prefer that setup.
One thing though that can be a little annoying is the hissing sound at certain rpms... I read it is due to the thinner stainless steel walls.
Also, in hindsight, I would have bought the overpipe too.


Oh and by the way I tested Petro-Canada 94 and I was able to add 2 degrees of timing above 4800 rpm. But I don't have dyno numbers for that.

[StraightOuttaCanadaEh]

Originally Posted by NicFromTheNorth

2 degrees of timing above 4800 rpm

sorry I'm a bit technically challenged. What exactly does 2 degrees of timing add?

wonder how much more noise the overpipe would result in

[tomm.brz]

it adds torque, ergo power

[jflogerzi]

It's kinda strange there are 2 dips... I would be curious to see what a stock car shows on that Dyno on the same fuel

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