"How much back pressure does a cat create" you ask?
A LOT! Period. The straighter and the emptier the routing, the better. No, bigger is not always better, 3" is the butter zone for 95% of dsms out there. If you need bigger, it probably shouldn't be driven on roads and should be shot right out the side of the car.
I made a cat insert for my etest last year. The hooks that held it into place broke and it was fired 1/2 way down my exhaust just from the build up of back pressure. Tis was without hitting boost btw... Why did it stop 1/2 way? Because it hit a bend in the pipe.
This was the interior of a stock cat, not a high flow. I can't comment on those.
After you put a turbo back exhaust on (because there's no point putting a cat back as you're still bottlenecking through the down pipe) you'll notice a massive difference in spool, acceleration, and overall power of the car regardless of turbo.

The FIMC will of course increase performance on any turbo once installed just by its size and effect on IATs in comparison to the stock side mount. Perhaps it's not "worth while" as you're still running a t25, unless you plan on sticking with a Garrett style turbo, but still a mod that is necessary. And it looks sexy .

Don't forget, with a 225 you're in aftermarket AFPR territory. Or a retired 190 for that matter.

I don't have any logs with or without a cat as that is long gone but I see about a 300rpm difference in spool up on my FP Red with my cutout open, which simply shortens the exhaust from 10ish feet to about 1.5 feet. Back pressure makes a big difference on a turbo car.

I would also agree that when buying a FMIC, go big on the first time. I learned the hard way that my Punishment Racing core is just not cutting it anymore with the FP Red.

If I was to do it all over again, dsmlink would have been the #1 mod.

Hm, maybe I will give my cutout a try!

I did NOT at anytine tell him not to get a fmic... But He just has the core..and is a student on a budget, why spend a ton of time and too much money trying to get it to work with his t25 when his budget could be better spent on other mods to squeeze out as much power as possible on the t25. I totally agree he should get a proper fmic.... But only when it will make a good amount of difference... Like with a 14b or larger turbo.

His FIRST mod is to get a clutch that doesn't slip. Than get all his mechanical amd maintence items upto snuff. Then enjoy the car....

Agreed, if that is the case he should probably just get a full exhaust and enjoy the T25 as is. Of course get a clutch that holds this power too.

Before modding I'd probably do all the safety stuff first, like brakes, tires, ball joints, tie rods, bushings if needed, and an alignment. Make the car drive proper before modding

Couldn't agree with you more! I took too long to do these and my car did some funny stuff. I still have my tie rods left to do in the front, then some stuff to look at in the back.

x2

The boost controller will only get you into trouble.. not help lower boost. Infact get the fmic, and all the sapporting mods, and a boost controller.. run that t25 to 17psi or whatever and tune it..learn the art of water injection! It will actually raise the affeciancy of the tiny compressor! Then once its not enough.. and it wont be, Ricers will still eat you alive.. Then upgrade the turbo to a much larger turbo. biggest turbo you can afford. Unlike 10 years ago.. the biggest turbos you can fit on our cars spool really fast. And some can be had for the same price as evo16gs.

If yer gonna spend the cash on all the supporting mods.. injectors...fuel management.. exaust.. cooling..etc..etc..etc.. well your gonna spend alot of money on your car.. dont spend all that money and then waste it on a small td05 turbo.

If you dont want.. or cant.. spend alot of money on your car. Then grab a 14b, safc, and do all the free mods you can. It will get you close to 300hp.

How do you figure? He'd be able to set a given boost and not run whatever the ecu feels like on a given day with the stock solenoid.

I actually put hks cams on my green car with t25 and picked up about 15hp at 17psi.

Why wouldnt you just remove the solinoid? wether you tune it with Link or just a safc and some evo injectors.. the car shouldnt hit any boost cuts.

That or if you're on the cheap, just get better airflow to the current SMIC. Most people take the duct out at some point and that renders the SMIC very ineficient. Just buy another one or make one. That'll get you the most bang for your buck on the t25. Even a 1g SMIC into a 2g is an upgrade if you get the opening ends enlarged. If you still have the restrictive plastic piping, that also has to go.

Because you might want to run at a specific boost level, he'll need one at some point, might as well now.

Well ya.. No point in running a t25 with out more boost then stock. Even a 14b will be too slow withoit a mbc. But if he threw a 14b on the stock manifold with stock 14b jpipe and some creative diy plumbing. The car will run fine with out the boost controller.

The previous owner had a manual boost controller but couldnt get it working (claimed the boost was flying all over the place) so it is still attached in my engine bay just no vacuum lines hooked up

a forge one similar to the one shown in this link

http://www.powershoponline.com/wp-content/uploads/2012/08/Manual_Boost_Controllers_Forge_UNOS.jpg

he probably had it hooked up backwards. i accidently did that when I was messing around and my boost was all over the place, some days consistent, some days not.

Glad to know you think I give bad advice Reza.

Choke on your popcorn

Yup first thing he should do is relocate his alternator to the back of the motor
IMO an alternator relocation should only be done if you 100% have to, not on a stockish 2g DSM. Great advice buddy!

You go man!

WTF are you talking about dude?

I was addressing his post regarding him rebuilding his alternator. And me stating that a Saturn alternator relo'd to the back of the motor is what a lot of guys have done. If not relo'd then at least the "upgraded" Saturn alternator.

It's helpful information. NOT HIS FIRST MOD!!

Lay off the pipe broseph!

Manny no need to upgrade to a Saturn Alt just cause this guy gets boners over them. Do a little research on your own If this guy can't get an OEM alternator going on his car, he's doing something wrong.

If you got frustrated installing an OEM alt in the stock location, relocating to the back of the engine would probably be the last thing you want to do. I've seen people do this, what a pain in the butt it is once it gets fucked up again, lol.

Guys like me have been on a stock OEM alt for years, WITH NO ISSUES AT ALL No need to fix something that's not broke.

Just trying to help you out here Manny, not telling you useless sh!t to do, just cause I feel like posting something

+1 mines been running 22 years this November. Thanks Reza glad I am not the only one.

Lol... Well i think hes got enough advise.. Common weve only perfected the upgrade path for dsms like 15 yea ago. Everyone will have a differant opinion..example.. Lots of guys will tell you saturn alternators is a myth, yet almost half of everyone who mods thier dsms uses a saturn alt.

Its up to you to pick which path to go. Do some research cause if changing the alternator is a pain.. Then maybe swapping turbos right now is not such a good idea.

Well, you're officially an asshole in my books.

Sounds good buddy!

Same here, stock location stock alt and no heat shields. Have even had some power steering fluid dripped all over it and she is still good.

Two of my buddies have had the relocation bracket break on them, so I said to hell with that when I saw how much of a pain it was to deal with it.

This is good and all guys.. But first... Maybe some of you are lucky and some arnt.. But it IS a known fact that DSM alternators.. For whatever reason are failing on our cars.. Theres tones of posts on it. So ya.. It is a common issue. Just because someone got lucky and never had a problem with their stock dosent mean they know everything and evryone else is wrong.....

And need to be a dic about it.

Were all here to help each other not ridicule everyone cause they dont follow a certin path or bandwagon.

Second ... I currantly run a staurn alt and a dsm alt and the saturn alt performs much better. Plus its cheaper to replace.

Wasn't this thread about a intercooler? How did you guys even start talking about an alternator?

Cause somepeople know more then others

Mike and Reza: Dont make me come over there and make you two hug

And to all i've made a few threads in the short time i have been part of this forum and a majority of them have lead to a lot of new knowledge for me.

Majority if not all threads have been started because of the unending list of questions i have as i am new to the dsm world and all the info has been helpful

Everyones opinions have contributed towards my questions being answered and i hope it continues this way...that being said no need to dog someone elses opinion we're free to have one and if you dont agree then thats also your opinion

At the end of the day im all for maximizing the return for every dollar i invest in anything and that will be my route with my cars upcoming lengthy slow'n'steady build.

Mike i believe had suggested a build thread and i will most likely be beginning that (once an income stream has begun) for anyone who wants to follow.

Keep up the DSM love peeps!

I've seen a few of these relocation kits break too. I remember Kevin K having a bitch of a time with his, I think he had to take off his intake manifold or heater hoses just to pull out the alt once, lol. He ended up putting it back in the stock location, along with his PS pump. I'd say your chances of breaking down somewhere and getting stranded are higher with one of these relocation kits.

As for the Saturn alt, big woot. I've had 4 DSM's with OEM alternators running perfectly for years. I still haven't found the need to switch over to one. There is no possible way that 50% of DSM's are on saturn alternotrs, lol. Not sure where you are getting these stats from. I'm not lucky just cause I have my car running good with no problems and so aren't the other guys running OEM alternators. If your having issues, you would probably want to find a new place that rebuilds your alternators, you must be getting some pretty bad ones or you definately have some bad luck

No... I dissagree... Ive seen 2 alts in my possession go bad. Both oem replacements. And ive read alot of post on peoples stock oem alts and oem replacements go bad. My 1g has its original 92 alt. Never had to replace it. But its not as constant and lively as my saturn alt. Which is placed in the stock location. When it dies.. If it does.. I will replace it with a known reliable saturn alt for half the price. Cheaper for me cause i have a good source. You can say im wrong all you want.. And question my stats or info.. I dont care. But thats not what were here for. Were sappost to be buddies.... To hang out with and have fun.

It does happen tho... Alot. And it IS a common fail point on our cars. You cant deny that. It comes up quite often on every forum. So dont say it will never happen.

Yes I do hear of it, but then again 50% or more of DSM's out there are hack jobs. That's a fact! Must be that half

Either you have wiring issues in your car, or your rebuilder is not replacing the regulator in your alernator. That is the common issue with these rebuilds. Ever wonder why your OEM one that came with the car lasted the longest? I use OEM rebuilds with the regulators replaced in them. That is probably why I don't have issues.

I have only had 1 alternator fail and that was in the evo on the way to the S.0, and it was the original as far as I know.

First of all, let's get it straight....everyone is entitled to MY opinion......

I think the problem with the brackets breaking on the Jay Racing relocate kit are what caused him to start offering steel brackets instead of aluminum. As far as I know, no-one has had one of the steel brackets break.

As for it being a PITA, and whether there are or aren't benefits, I have no opinion, so I will also just grab popcorn.

Bang on. A lot of these rebuilders in this business are a joke.

Like i siad... Both alts that died on me were oem replacements. Straight from the dealer. And now ive hard and experianced 2 alternators die in my 2 trips to shoot out. They were the only casualties that i know of in 2 years of going to shoot out.( not counting Tims evo falling apart on the way home). I blieve Eric is on his 3rd oem alt. but shitty alternators or not... The saturn alts put out more amps.. And have a better ability to compansate for sudden changes in load.
But thats not really what this is about. Oem.. Saturn... What ever chose what you like there are milions of post about this topic. And i dont beleive im gonna change anyones mind after they been doing this for so long. BUT.. the whole point of my position in this thread was to defend Mike. As the OP had mentioned the alt replacement to be a pain in the ass..... And mike suggested a differant route ...A common route. It was never bad advise. Im sick of people giving their opinion and suggestions and then getting sh!t on by people who think their gods

MANNY if you want a easier way to replace your oem alt IF it ever needs to be replaced( and they do... All alternators do.. They wear out) Try my idea. I mounted my power steering pump to the back of my motor instead of the alt relocation. This cleaned up ky engie bay alot... Stopped the risk of dripping pwer steering fliud on my alternator and made swapping alternators a freaking breeze!