s4 or s5 ?
#26
always searchin
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your "friend" was about to rip you off, so i wouldnt consider him a good one... if one at all. $1500 will get you an entire 13BT swap and it's well worth the money spent.
#27
kk thanks alot ill check them out, as for the exhuast, i removed one of the pre cats and the main cat and just put a pipe there but i left one of the pre cats, was that a bad thing to do?
know what is this VDI for?
is a single exhuast better or a dual exhuast for these cras?
know what is this VDI for?
is a single exhuast better or a dual exhuast for these cras?
VDI= variable Dynamic Intake. the 5th and 6th ports open up at higher RPMs (as eric stated, like Vtec) along with the secondary injectors kicking in. Some people have disabled it and have WIRED their 5th and 6th port open (loss of hp/tq at lower RPMs). I don't think it applies to S4s though. There ARE some threads out there on how to MODIFY your S4 with S5 Intake but i've never looked into it.
I know some people have problems because their 5th and 6th ports don't open after they removed the cats but again I'm not too familiar with the S4 so the S4 guys will be able to clarify this for you.
As far as which exhaust is better? It's all up to you and what your needs are. If you live in a place that has emmissions/lots of cops/old people/or a billion riceres revving at you because your car is loud then I would MOST DEFINITELY recommend the Racing Beat collected header manifold-back exhaust.
If you don't have to worry about any of the issues above then get any open exhaust (dual or single does not matter except that the duals supposedly lower NOISE emissions) but remember the NA LOUD with open pipes. It sounds great for the first 15 minutes. Any longer than that and you're going to need earplugs, unless you've already tried to turn the car on with only a header, in that case you're already the happiest deaf person in the area.
Originally Posted by FAQs at the top of the second Gen section. LOOK HERE FOR MORE INFO!!
How do I tell the difference between an S4 and S5 engine?
See the following topics:
https://www.rx7club.com/forum/showthread.php?t=530583
https://www.rx7club.com/forum/showthread.php?t=263870
Lots of Info: https://www.rx7club.com/forum/showthread.php?t=373451
Pictures: https://www.rx7club.com/forum/showthread.php?t=341891
https://www.rx7club.com/forum/showthread.php?t=330057
Good thread: https://www.rx7club.com/forum/showthread.php?t=594874
See the following topics:
https://www.rx7club.com/forum/showthread.php?t=530583
https://www.rx7club.com/forum/showthread.php?t=263870
Lots of Info: https://www.rx7club.com/forum/showthread.php?t=373451
Pictures: https://www.rx7club.com/forum/showthread.php?t=341891
https://www.rx7club.com/forum/showthread.php?t=330057
Good thread: https://www.rx7club.com/forum/showthread.php?t=594874
#28
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I used to have an RX-7 with the pre-cat removed and it ran pretty strong. A friend complained that my old one felt a little faster than his. So I presume the 5th and 6th ports were still opening. My old one still passed smog, but not by much. If you removed both cats, then you need to do a search to figure out how to activate your aux ports via air pump. Until then you've lost 25 HP and gained 15 or so.
VDI: Do a search. I don't understand it too well myself. It varies something in the intake according to rpms or some mojo like that. I dunno.
Single or Dual Exhausts: Doesn't make much of a difference, I don't think. Supposedly dual are slightly better.
VDI: Do a search. I don't understand it too well myself. It varies something in the intake according to rpms or some mojo like that. I dunno.
Single or Dual Exhausts: Doesn't make much of a difference, I don't think. Supposedly dual are slightly better.
#29
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I've swapped an s5 longblock/tanny into my s4 gxl and it was a pita to iron out all the wiring gremlins and I don't suggest anyone do it. The only reason iI did it is because I had a steal of a deal on the rebuilt engine/new clutch/harness. I also run a full 2.5 straight through exhaust (header/no cats/magnaflow can) with no problems from cops but maybe its different in Canada.
#30
So you have a precat but no main? I'm confused, I thought there was only one of each. I'd do a search to learn how to check your 5th and 6th ports just in case. I think you just smear some white grease in the right spot and see if it gets rubbed off when you rev over 4000 rpm.
#31
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So you have a precat but no main? I'm confused, I thought there was only one of each. I'd do a search to learn how to check your 5th and 6th ports just in case. I think you just smear some white grease in the right spot and see if it gets rubbed off when you rev over 4000 rpm.
--[]-[]--[]------------ it lookd like that lol
#33
ohhhhh, that explains it. Learn something new every day. Wait, didn't he say he had an 87? That's s4. If he has an s5 the the 5th & 6th are opening via air pump and WhiteBoyzRacing has nothing to worry about. If it's an s4 or if he doesn't know he should check them to be sure.
#34
Don't hate my V8
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HANG ON, the aux ports in a NA car are nothing like v-tech other then the fact that it adds more power at higher RPMs. the aux ports just open to let more air/fuel mixture into the engine, v-tech changes the valve timing and angles while running to extract more power. thats Y a v-tech cam looks so weird compaird to "normal" ones.
#35
Engine, Not Motor
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Actually, the aux ports are almost exactly like V-Tech. V-Tech changes the valve timings, the aux ports change the port timings. Same difference. In the case of the aux port system, the 5th and 6th ports greatly delay port closing when open.