impactwrench

Put a tennis ball in your exhaust pipe. No more creep

dradon03

iTrader: (2)

^

PFC, Boost Controller
DP, High Flow Cat, 3' C/B No problem???

TrevorC

haha! lol.

Is there a how-to on porting the wastegate? My car has a midpipe with no resonator / cat also.....and I get boost creep also - I've just been staying out of boost for now as I have a boost problem currently also (recent) (having to do with the solenoids).

axr6

I had a perfect conrol of my boost with my PFC until I replaced my main cat with a Metallic Substrate cat. Of course I have the rest of the exhaust pretty much open, with intake to match.

Now, I hve boost creep because the metallic cat basically flows almost as free as a straight pipe. Somewhere I read a figure where it stated that a met cat flowed 80+ percent of straight pipe. So, if you consider that the met cat is housed in a 4" pipe configuration, 80 percent flow though it would exceed the flow rate of a straight 3" pipe. Thus, my boost creep.

I am laid up, hurt with some seriously broken spine and neck now but, have already received my Supertrapp, disk only setup. If you do not know what that is, go to Summit racing catalog, search for Supertrapp and you'll get the idea. It allows you to fine tune your back pressure and get exactly the degree that you just need to keep you from boost creep. Point of warning: if you chose the absoute max number of plates that you can get away without boost creep at a given warm temperature, you may still get boost creep at colder ambient temps. So, with this system keep you eyes on the temps and on your boost gauge and set your fuel cut tight.

The cost of this add on mod is less than $100 including shipping and an additional 6 pack of disks. I figure that the included 12 plates pluse the extra 6 should be about in the range where I will need to be. AN other plus with this setup that Supertrapp's original purpose was for sound control for race cars. So, your screaming beast will actually be a bit quiter.

Of course the ultimate solution is to port you wastgate as others suggested but, unless you want to remove your turbo and do a lot of work, this is a pretty good alternative, giving you max power and still a cat that will probably pass smog (I inlcuded an air pump pipe when I built this cat).

Good Luck

the_saint

your car will sound like an outboard boat idling.

At WOT it will be very loud, but sound nice.

It will drone ALOT. A resonated midpipe (I am using a Borla XR-1 Sportsman Oval) will help alot, but will not get rid of the droning.

California Dreaming

I put a high flow cat on my midpipe and that barely changed the sound at all. I am about to throw on my resonator to try and quiet things down a bit. It really is dumb loud and thats not a good thing if you live in a conservative community like me haha

axr6

I find is interesting that so many forum members are so much against loud exhaust. I personally only hate loud exhausts on Harleys and ricers that basically make a lot of noise but not speed. Even before I spent all those years in all out race cars, I opened my fast car exhausts to sound as fast as they actually went. For me the speed and the sound are necessary pairings for a true sports car experience.

My first FD was also a daily driver while doing part time race track duty. I ran it with staight 3" pipe for cat back and DP and liked the sound under WOT where the thing had spend much of its life with me. I have absulutely no problem with the noise of my present FD with the DP, Met Cat and Corksport canister. Loud but, it sounds like a beast that means business. Kind of intimidating for the light hearted. Also, it help when the wife can hear me coming a couple miles away and have dinner served upon my exact arrival.

Still nothing like the sounds from my J-Bridge ported race engines from my GT2 and GT3 cars. Now, those was a sounds that would wake the dead at 9400 RPM. Earplugs mandatory inside your helmet!.

M14socom

Is there any information on how this is done? How much would it run to have someone port it? What is a good aftermarket wastegate you would suggest for "downpipe, midpipe, apexi n1 catback, and greddy trust intake?

California Dreaming

Search before you get flamed my friend. If you already have the turbos removed it should be around $50 to have the wastegate ported. The stock turbos cant use an aftermarket wastegate because our wastegates are internal and built into the turbo manifold itself.

-Neal

dgeesaman

iTrader: (7)

1) There is no aftermarket wastegate for stock turbos
2) There is a recently added link in the FAQ under 'wastegate porting'

Dave

ITR

iTrader: (1)

I have just removed my CAT and placed a mid-pipe. Are you guys saying that this is not good for the stock ECU or would it increase the boost automatically harming the turbos? My D/pipe is still stock though. I am confused can you help please? Thanks!

SiKoPaThX

iTrader: (2)

1. You should have replaced the stock downpipe (precat) before the main cat.
2. Running a midpipe will increase the boost automatically which on a stock ecu will cause a lean condition in the engine. This will lead to detonation and apex seal failure.

To be clear, I am saying this would not harm the turbos, but instead cause you to blow your engine.

There is no way to prevent the automatic rise in turbo boost other than porting the wastegate or adding more restriction to the exhaust system.

My advice is that you put your main cat back on the car and then seek a replacement for your downpipe (precat).

ITR

iTrader: (1)

SiKoPaThX thanks for your reply. I am running the engine on 3mm apex seals. Will i still harm the engine?

GoodfellaFD3S

iTrader: (213)

Yes. Mr. V8 advocate is correct......you need to put your main cat back on, get rid of the midpipe, and install a downpipe instead (deleting the first cat/stock dp as you call it).

The way your setup is now, you will probably be ok b/c the stock dp keeps some exhaust restriction. the problem is that they tend to clog up b/c they are so close to the turbos. this will cause motor failure as well.

Using both a downpipe and a midpipe on stock wastegate and turbos, your boost will go too high and your 3mm apex seals will break.

Shinobi-X

On a street car, anything too loud is just obnoxious IMO. A bit louder than stock is fine, but for the sake of neighbors and cabin conversations, I just never found it necessary to be louder for the sole purpose of it. I currently have a large streeport w/straight exhaust leading to an RB dual tip, and it sounds very aggressive. However, I'll definately be welding in my metal cat now that I've heard things for myself.

ITR

iTrader: (1)

I have contacted my local Rotary mechanic and told me that changing the midpipe wouldn't effect whatsoever the engine. He told me that the turbos have a restricted boost too. He tried to convince me that a mid-pipe wouldn't do anything wrong to the engine....I am more and more confused!!

GoodfellaFD3S

iTrader: (213)

Your local rotary mechanice doesnt know jack **** about FDs.

Sgtblue

iTrader: (16)

Consider finding another mechanic, I think he's giving you bad info. If you keep the stock downpipe, your risking damage because they tend to plug up. Not only that, they cause ALOT of underhood heat which bakes plastic, vacuum lines etc. and that eventually causes other problems.
As Goodfella said.....change the stock downpipe out with a decent aftermarket downpipe. Put your stock cat back on, or get a nice high-flow cat (Bonez and many others are good). DO NOT run an aftermarket downpipe with a mid-pipe on the stock ECU. You risk boost creep, causing your engine to run lean and detonate. I'll stand corrected, but I think the 3mm seals are mostly for running higher boost WITH ALL THE OTHER NEEDED MODS, like fuel mods etc. They won't protect you from detonation. If your mechanic disagrees, have him register here on the forum and (try) defending what he's telling you.

ITR

iTrader: (1)

HOw can they clog? With a Exhaust you mean?


I'll try to check the boost on the boost gauge. Would this help? What is the normal boost for a stock engine? Last time i checked, it was 0.78 (with the stock CAT installed) ?

Shinobi-X

The stock forward exhaust system consist of a catalytic converter (pre-cat) for emissions purposes. Given the course of time they need to be replaced if in poor condition so that they do not restrict exhuast gases leaving the engine and especially in the case of our rotary engines, heat. People running too rich, overheating the exhaust, poor air pump, etc. can all cause the catalytic converter to see less life.

You also need to STRONGLY consider getting a new mechanic. Changing the mid-pipe or any other piping in the exhaust system will effect a turbo engine...how else do you think people are able to make power by freeing up the exhaust? Catalytic converters (stock) are very restrictive, thus removing them allows a lot more exhaust to flow out of the engine, meaning it has a direct effect. Any mechanic who doesn't understand this basic principle sure as hell doesn't deserve your business.

The stock turbo SYSTEM is restricted to a max of 10 psi (normal boost), but going over that is not something you control with a boost controller when boost creep is the problem.

SiKoPaThX

iTrader: (2)

It might be the effect of having a bad past 6 months with the rotary. Trust me, when it's running right I love it. It just seems lately that something is always going wrong

TrevorC

I need to know how much I can get for my stainless steal catless / non-resonated midpipe......after reading this thread it scares me, so I'd like to sell the aftermarket used one, and buy a stock low-milage / new midpipe with the stock cat.....how much could I sell it for?


or should I just buy a high flow catalyst converter? And I could get it welded in by my local exhaust shop into the midpipe? And then buy a Racing beat catback single tip muffler? Would that be a good combonation?

also, I would need to buy a new o2 sensor for the cat? Or could I just leave it without one and plug the o2 sensor hole in the cat? (because I'm not worried about emissions, just trying to reduce boost creep by putting in a cat)

axr6

Don't worry about the O2 sensor. It is located in your downpipe or precat near the turbo exhaust manifold. The main cat has in airpipe from your airpump (if you still have it) to deliver oxigen to the cat to complete the burning of unburned exhaust products. I prefer to get a high flow cat that has an attachement for the air pump as it will help you pass emission testing and may actually extend the life of your cat.

Any decent muffler shop should be able to weld in a high flow and even construct an airpipe for your airpump. I did mine at home and I am not even a decent welder. As to the cat back, most people here seem to favor the RB duals.

Edit: My High Flow recommendation was for a traditional ceramic cat. The new metallic substrate cats may flow as much as a straight mid pipe, presenting you with the same problems. Ceramic high flow cats seem to have an established record for not causing boost problems.

ITR

iTrader: (1)

Hi Guys! Thanks again for the help and info. I went to another mechanic in my area and confirmed wat you said to me. I then checked again on my car and had the fright of my life. I have blitx turbo timer which also reads boost. The boost gauge marked 1.68 yesterday ! I am going to take my car to the new mechanic next Friday. Could this be related to what you guys were tell me? THanks again!

GoodfellaFD3S

iTrader: (213)

That's like 25 psi! Aye Carumba!