Ace 350 vs JDL 4-2-1
 

Hello ft86 friends,

I have HKS catback, Grimmspeed CAI, and OFT stage 1 tune.

I am looking to move on to stage 2 and I wanted to get EL 4-2-1 headers and I am having trouble deciding between these two setups.

Looking at dyno numbers I can't really compare as the graphs on both product photos seems to be measuring at different points. Is the Ace 350 that much better than the JDL or is the difference in gains not worth the extra 700 dollars?

With the OFT can I pay OFT to make a custom tune for my new setup or would the OTS stage 2 you download be good enough?

Be aware that advertised gains are usually from some quality dyno time.

OFT will not give you the best out of either header.

Hp/tq will be left on the table.

So, in saying that, I would get the ACE and get a "good" tuner to spend a few hours with it on a dyno.

If you don't have the funds for thr ACE and tune then.....

Get the JDL and with the saved $700 get in a few hours of tuning on the dyno.

Disclaimer: "good" tuners are pretty rare, usually booked out months in advance and demand high price, average tuners are everywhere.

OFT are a cheap and nasty fix for the most critical part of any modification, the tune.

In the end you get what you pay for.

The ace is definitely better, but up to you if it’s worth the extra premium for the added performance. Just look at as many before and after dynos and compare the % increase between the runs and see what one had the higher % increase, don’t just look at the peak hp or even hp gain. The only somewhat consistent number to look at is percentage increase
before and after. And the more points you references the better as well for a more complete comparison. Like top end peak and mid range and a few points in between.

Any 4-2-1 header will need a custom tune or at-least a specific OTS tune for that header. OFT OTS tunes are for 4-1 headers and slightly more optimized for UEL at that.

There's just not enough data out on the JDL to rule it out, but the ones that are out in the wild the look promising. To be honest a lot of people will just say the A350 is better because it's more expensive, they're probably trying to justify its price premium.

My arm chair guess is that the JDL will easily get you 99.95% of the gains the ACE will at a much lower price point. But take that with a grain of salt until we see some hard back to back numbers from a JDL/A350 shoot out, which may never come.

Either way with out a proper dyno/tuner either will be overkill and you may be better off getting a Tomei EL header.

Either your gonna need a custom tune be it OFT or ecutek. Ace is established as most ppl know how to tune it. To unlock JDL's full potential could take time. You can't go wrong with either. One thing to note Ace replaces Overpipe and JDL keeps it.

You'd be happy with either one. OFT can handle either with data logging and a proper etune from some of the some of the more competent OFT tuners on the forum. It's been proven fine for NA applications ad nauseam. However there are many more Ecutek tuners with maps already adjusted for either header so turn around time may be better.

Nailed it. The ACE hype is from cherry picked dyno graphs that were retuned 10+ times. ACE claim to fame was marketing 200+hp on pump gas like it hadn't been done before. CSG will chime in to tell me I am wrong.

The oft is good for a general tune. It is not worth a custom tune from shiv himself. Even tho you pay for a etune, he will take weeks/months to reply back. There are several people on here to back up that evidence.

That's it. Outside of the nice bells and whistles Ecutek offers (which are kinda neat) a good tune boils down to optimized fuel, timing, and VVT maps. OFT will do just as good of a job *technically* as Ecutek. The catch here is the tuner, far more important than OFT vs Ecutek. Thing is, most tuners don't offer custom tunes for OFT, which is why Ecutek is ultimately better. But for NA where you're not trying to squeeze the last 2hp out of your setup, often OFT is fine. Moving on to FI, fine tuning becomes *much* more important for power output and engine longevity - custom tunes (ideally with dyno time) are the only way to go here, so Ecutek is really the only option here (also better for things like failsafes).

P.S. - I'm happily running OFT on my NA 4-1 EL header setup. If I go FI, I will switch to Ecutek.

For a 4-1 "generic" header OFT OTS tune will get you 90% of the gains and a custom tune/e-tune isn't necessary. but the more unique the header design and especially when it is a 4-2-1 header you really don't get much from a OFT OTS tune, and need either a custom tune/e-tune or at least a OTS tune specific to that header to really get all the gains.

Yeah I tend to thing that's one of the biggest benefits of the ACE headers, they offer a well vetted starter tune along with optimization once you put it on the car. Smart idea - I think other header manufacturers would benefit by following this model and partnering with a tuner.

Also I think there's a good mix of 4-2-1 EL headers (mine is 4-1 EL) for the 86 platform, I always thought the EL OTS maps from openflash were 4-2-1 optimized, but I don't really know - where do you get your info from regarding that? if it's 4-1 optimized then maybe that makes sense why their stage 2 EL tune works so well with the P&L unit I have.

Yes, if you respect your car, dynotune it
If u dont respect your car "toon" it

Dyno tune by the right person. If there are no reputable tuners in your area, use an ots or remote tune.

Specifically, 200+ on ACN91, which, wasn't done before, and still hasn't been repeated by any other header

Many setups will hit 200 with a catless front pipe and/or better fuel.

ACN91 sucks.