p/n for OEM JDM DP?
#2
Rotary Freak
iTrader: (1)
I also see this one listed as the “280hp” version: N3G140500B
Nengun has your part number priced, not sure where youre ordering from. https://www.nengun.com/oem/parts/MTE...N5c3RlbSAobXQp
Nengun has your part number priced, not sure where youre ordering from. https://www.nengun.com/oem/parts/MTE...N5c3RlbSAobXQp
#3
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 31,121
Received 2,786 Likes
on
1,972 Posts
the N3A7-40-500A is the 265ps version, N3G1-40-500B is the 280ps version. 280ps is slightly larger in diameter
they both are available, price is close, i'd go with the 280ps version
they both are available, price is close, i'd go with the 280ps version
Trending Topics
#9
RX-7 Bad Ass
iTrader: (55)
I seem to remember that Mazda increased the downpipe diameter on the 99 280ps downpipe, that was in the literature when they were talking about all the changes - better IC ducting, abradable seals on the compressor housing, etc.
I think the difference is pretty small, like millimeters. Any aftermarket downpipe would outflow it by a large margin.
I can see the appeal of having the stock part especially in areas like Cali where it could be inspected.
Dale
I think the difference is pretty small, like millimeters. Any aftermarket downpipe would outflow it by a large margin.
I can see the appeal of having the stock part especially in areas like Cali where it could be inspected.
Dale
#10
RX-7 Bad Ass
iTrader: (55)
From https://robrobinette.com/sae_article.htm
Dale
In the exhaust system, the front tube gauge has been reduced by 0.5 to 1.0 mm (0.02 to 0.04 in.) so that flow passage is increased while retaining the tube's outer diameter. The main silencer has also been redesigned. These changes result in about a 10% reduction - about 13kPa (1.9 psi) - in exhaust gas resistance.
Dale
#11
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 31,121
Received 2,786 Likes
on
1,972 Posts
#12
From https://robrobinette.com/sae_article.htm
Dale
In the exhaust system, the front tube gauge has been reduced by 0.5 to 1.0 mm (0.02 to 0.04 in.) so that flow passage is increased while retaining the tube's outer diameter. The main silencer has also been redesigned. These changes result in about a 10% reduction - about 13kPa (1.9 psi) - in exhaust gas resistance.
Dale
The following users liked this post:
GoodfellaFD3S (05-27-24)
#15
Rotary Enthusiast
iTrader: (32)
I heard that the HKS DP has attachments for the upper heat shielding from the OEM DP? That would indeed make it a somewhat safer choice for California smog check. BUT, I would still have some concern - last time I did smog check on my FD (which has a JDM DP) I went to a different shop since the regular one was down. Anyway this guy was super vigilant and he actually had his dyno installed between a vehicle lift and lifted my car for a walk around undercar inspection. I think any DP other than stock with cat or JDM would have been failed. I was a little concerned that even the JDM would not pass visual, but it did. JDM for the win IMO in California.
Last edited by jza80; 05-10-19 at 01:06 PM.
#17
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 31,121
Received 2,786 Likes
on
1,972 Posts
you are going to get the one you ordered...
#19
RX-7 Bad Ass
iTrader: (55)
Post some pics when it gets here, I'm interested to see how a brand new one looks.
Dale
Dale
#21
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 31,121
Received 2,786 Likes
on
1,972 Posts
these aren't superseded, there is the 265ps part and 280ps part. if it did supersede you'd be right. (sorry, parts are my job, its nit-picky! )
The following 2 users liked this post by Narfle:
Nakd n Fearless (06-12-19),
Redbul (10-24-20)
#24
RX-7 Bad Ass
iTrader: (55)
Wow that is pretty!
Dale
Dale
#25
I don't have a caliper handy, but IIRC it is 65.2mm, which is roughly 2.5". The restriction lies with the kinks in the cast, and it's pretty tight in there. I'd speculate the cross section is similar to a 2" pipe. No wonder people gain so much power with a fat DP. Extrude hone is the first thing that came to mind.
I thought it would be cool to cast a US style DP head to hook up to 3" pipe, so you'd get HKS stud fitment with US style flow and aesthetics. With rapid prototyping etc, it's probably not unrealistic to do a "small" cast run.
I thought it would be cool to cast a US style DP head to hook up to 3" pipe, so you'd get HKS stud fitment with US style flow and aesthetics. With rapid prototyping etc, it's probably not unrealistic to do a "small" cast run.
Last edited by Narfle; 05-13-19 at 02:20 PM.