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Prospeed Hi-Flow Catalytic Converters

Re: PROSPEED Hi-Flow Catalytic Converters!

Prospeed, sorry about getting on your case, but I have question. Do you know what the expected service life of your cats will be?

The EPA (US Environmental Protection Agency) states here that OEM catalytic converters must be built to last the life of the vehicle (usually 100,000 miles). Since they are so expensive, the EPA allows aftermarket cats to last only 25,000 miles. That way, they can be made more cheaply and more people will decide to replace their OEM cats if they no longer function. (EPA reasoning in that link)

If the OEM cats last four times as long as aftermarket cats, then aftermarket cats may actually be more expensive in the long run (if you plan on keeping your car) unless they are 1/4 the price of OEM cats.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

someone mention in another thread that headers causes cats and 02 sensors to wear out more?
 
Re: PROSPEED Hi-Flow Catalytic Converters!

If the OEM cats last four times as long as aftermarket cats, then aftermarket cats may actually be more expensive in the long run (if you plan on keeping your car) unless they are 1/4 the price of OEM cats.

Pretty close. OEM cats retail for just under 2600USD for a set. If an aftermarket set passes smog then take the money you save and buy bond ladders. If both cats fail after 25,000 miles cash in some bonds and buy another set. Don't forget to factor your utilty for any HP gains into the financial cost model. I think $40 present value per is fair. :smile:

The good news is that motorists in CA are exempt from EPA laws. The bad news is that motorists in CA are exempt from EPA laws. ;)
 
Re: PROSPEED Hi-Flow Catalytic Converters!

I am interested, but would want to learn more about the benefit of the high flow cat. i have read from other post showing that the gain is minimal, so what to expect from you cat, Brian?
 
Re: PROSPEED Hi-Flow Catalytic Converters!

Hi everyone,

I've been out of town so I haven't really had a chance to answer everyones questions.

No, headers will not wear out cats or O2 sensors, however poor a/f ratio (running rich, etc) will cause damage to both cats and O2 sensors.

How long will the cats last? We have seen them last with no problems for over 2 years now (and still counting) with about 20,000 or so miles on it.

I believe they are cost effective even with minimal HP gains. Even if gains are 2 to 3 hp I believe the light weight and improved acoustics from the exhaust will make it well worth it. If you have damaged cats then this mod makes it more then worth it considering the OEM cats cost $2000+. They are priced about 1/4 of the price of the OEM cats so thats a good thing.

I also agree with MvM I recommend going with what will pass the sniffer in your area. If you can have increased flow and still pass emissions then its a win-win situation! :smile:

I have a day set aside to dyno next week when I get back into town. I will have before and after dyno testing including installation pics. I will also have OEM cats vs. Hi-Flow cats Video with sound.

Hang on tight guys! Thanks.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

When will you know which cats will pass CA smog?

EDIT: OK I went back and read the thread again and it looks like 300cell will pass smog. Have you tested the 400 cel on OBDI for CA smog?
 
Re: PROSPEED Hi-Flow Catalytic Converters!

Hi Paul,

If I get enough people getting on the list for the 95-99 style OBDII Hi-flow cats I might be able to do it for cheaper. Possibly in the range of $525 to $550 for the set(GB price). Again this depends on at least 5 people getting on the list.

Let me know guys so I can give you guys a better price. :smile:

7 Spots left!

why are the OBDII cats cheaper than OBDI?
 
Re: PROSPEED Hi-Flow Catalytic Converters!


Saw these (300 cell) in person, and they look really nice, and weigh about 7 lbs. I'm pretty Brian will have these done next week or so. Awesome craftsmanship. Can't go wrong with these cats. Brian can also make them custom fit. Can't wait to have have them on Sakura-chan :biggrin:
 
Re: PROSPEED Hi-Flow Catalytic Converters!

I can do a custom one for you if you wish to have a 300 cell. I am not sure how stringent UK is regarding emission control. The 300 cell should not throw a CEL and it will give you the best flow for the OBDII cars. As of right now the price for the OBDII will be the same. If I get enough people getting on the list for the 95-99 style OBDII Hi-flow cats I might be able to do it for cheaper. Possibly in the range of $525 to $550 for the set(GB price). Again this depends on at least 5 people getting on the list.

Let me know guys so I can give you guys a better price. :smile:

7 Spots left!


So is this group buy still going on?

I'm interested in the 2.25" 300 cell version for a 1991. Are we now looking at $525? If so, add me to the list.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

So is this group buy still going on?

I'm interested in the 2.25" 300 cell version for a 1991. Are we now looking at $525? If so, add me to the list.

Hi You have PM.

UPDATE

Sorry guys I've been so busy with my move I haven't had time to get everything done. I have the first batch done! Here are some pics. I will have them ready to ship out by early next week for those who ordered first.

I will continue to extend the GB price to everyone for another 2 weeks. The jigs are pretty much done for the 95-99 style headers and the 00+ will be done shortly. I will have pics up as soon as I have everything done. Thanks for your patience guys!

IMG_9239-OL.jpg


Here are Prospeed Hi-Flow cats next to a set of test pipes!

IMG_9246-OL.jpg
 
Re: PROSPEED Hi-Flow Catalytic Converters!

Hello Brian,

Thanks for the update, items are looking very good.

Have you done a dyno yet? And actual weight?
Am interested in HP numbers always as you know. Sound is less important for me as my NSX with the Taitec GTLW is already more than loud enough. (A little less would actually be better I think)

Also have another question and has to do with something Greenberet told my a while ago.
AFAIK, the OEM cats have heat-shields attached to them. These new one don't have these.
Is there a chance that these cats will increase my oil-temperatur in the oilpan? Especially on long high-speed runs.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

AFAIK, the OEM cats have heat-shields attached to them. These new one don't have these.

You can use the OEM heatshields around the sporty cats as a friend does too.
 
Re: PROSPEED Hi-Flow Catalytic Converters!


In this pic, the cat on the right don't seem to have a straight flush through the flange... it seems like its sideways or something.. when connected to the exhaust, i think the flow won't be straight as it passes by the flange...

can you elaborate on that?
 
Re: PROSPEED Hi-Flow Catalytic Converters!

That looks like its just the nature of the beast to try to fit everything into a tight spot. Those pipes are mitered nicely and personally, I won't be concerned on airflow, but thats just me.
Trev
Now send me my free set to test....lol

Wonder if you could offer a precat bung in those for the FI guys that aren't running Aem and want to have a bung for dyno or for wideband gauge indash.
 
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Re: PROSPEED Hi-Flow Catalytic Converters!

In this pic, the cat on the right don't seem to have a straight flush through the flange... it seems like its sideways or something.. when connected to the exhaust, i think the flow won't be straight as it passes by the flange...

can you elaborate on that?

You can't really see but it actually bends back flush at the very end. Also your whole exhaust system consists of bends. The exhaust doesn't get affected by bends as much as length or diameter of piping.

Thanks Trev for the comments, as a matter of fact I can weld bungs on there for wideband use or any other use.

UPDATE
-Weight? Both cats together weigh 10.6 LBS
-Prices Still available at $575 (2 cats with hardware and gasket included in the price)
 
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Re: PROSPEED Hi-Flow Catalytic Converters!

Hi Maarten,

Dyno appt is set I'll be on very soon. I will post up the sound clip this weekend when I get a chance to upload it. Actual weight is 10.6 LBS.

I don't believe heat will be an issue as far as affecting your oil temp at the oil pan. Both cats are set behind the oil pan relative to the motor and when you accelerate I'm sure it will produce as much heat as your headers and exhaust does normally. The header runs below the oil pan and that should produce more heat then the Hi-Flow cats. Also I will be installing this.... just like the McLaren F1 in its engine/exhaust bay to control heat on my oil pan =) A lot of the Formula cars in general use it on their intake ducting however I dunno about all that gold in my engine bay! hehe :smile:

800px-1996_McLaren_F1_engine.jpg


gold_foil.jpg
http://www.crracing.com/racing_performance/products_pics/gold_foil.jpg


Hello Brian,

Thanks for the update, items are looking very good.

Have you done a dyno yet? And actual weight?
Am interested in HP numbers always as you know. Sound is less important for me as my NSX with the Taitec GTLW is already more than loud enough. (A little less would actually be better I think)

Also have another question and has to do with something Greenberet told my a while ago.
AFAIK, the OEM cats have heat-shields attached to them. These new one don't have these.
Is there a chance that these cats will increase my oil-temperatur in the oilpan? Especially on long high-speed runs.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

i know this is offtopic but prospeed ive pmed you twice and you havent responded.
 
Re: PROSPEED Hi-Flow Catalytic Converters!

So your back in town now? I'm still waiting on those instructions. If I send you my chip this weekend when coudl I have a new one back?
 
Re: PROSPEED Hi-Flow Catalytic Converters!

So your back in town now? I'm still waiting on those instructions. If I send you my chip this weekend when coudl I have a new one back?

1 to 2 days to have the ecu back in your hands. Instruction will be sent in a few hours! Thanks!
 
Re: PROSPEED Hi-Flow Catalytic Converters!

In this pic, the cat on the right don't seem to have a straight flush through the flange... it seems like its sideways or something.. when connected to the exhaust, i think the flow won't be straight as it passes by the flange...

can you elaborate on that?

looks like a 90 degree mandrel bent pipe was used rather then a 45 degree mandrel bent pipe. :confused: hope mine aren't made this way
 
Re: PROSPEED Hi-Flow Catalytic Converters!

looks like a 90 degree mandrel bent pipe was used rather then a 45 degree mandrel bent pipe. :confused: hope mine aren't made this way

There wasn't much room because of the core and also the bend this doesn't reduce or hinder the flow of the exhaust.The 45 wouldn't have worked because of the reduction from the core. If you look carefully you can see it actually curves back near the flange. You don't need to worry about it affecting performance it will be fine. :smile:
 
Re: PROSPEED Hi-Flow Catalytic Converters!

UPDATE

Here are the pics of the install as well as a small video/sound clip of the stock OEM cat VS. The Prospeed Hi-Flow Cat.

Keep in mind this clip is a before and after installation. 65 miles on it, so far so good. The exhaust doesn't smell foul like some of the test pipe cars I have been around. The pitch has changed slightly and for a lack of words it now has a deeper "GROWL" It is however tame around town but once you get on it you it is slightly louder. Quieter then I expected. I also noticed better throttle response and increase HP. I will have dyno graphs up shortly to confirm.

Installation time Approx. 30-45 mins including cooling time.

Here are the pics....

Here is the factory cat opening. It's smaller then 2 inch's! You can see the black ring of exhaust around it where the exhaust meet up with OEM cats.

IMG_9253copy.jpg


Here is a closer pic of the welds

IMG_9249copy.jpg


Installation

IMG_9256copy.jpg


I wanted to show you how well the cats fit. You can see it is held loosely with perfect fitment.

IMG_9259copy.jpg


The Finale!

IMG_9262copy.jpg


Here is the video clip! Enjoy!

<embed width="448" height="361" type="application/x-shockwave-flash" wmode="transparent" src="http://i17.photobucket.com/player.swf?file=http://vid17.photobucket.com/albums/b68/coldfizzle/PROSPEEDHi-FLOWCats.flv">
 
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