I have been looking at downpipes and exhaust online from ipd and other companys and they just seem way to expensive for what they actually do. I know how to weld and i am pretty sure i am skilled enough with metal to build my own downpipe and exhaust. I do not have a machine to bend metal but will buying bends and cuting them to fit work fine? I have noticed that on the downpipes you can buy that they come with that flexing material on the pipe. Is that material necessary on the downpipe? Do i need to worry about not having that material on my downpipe if i make my own? Is there anything else that i need to worry about when making my own exhaust and downpipe? I was thinking about making my own 3in. downpipe and exhaust and i was wondering if anybody has any comments on my choice of size? Is 3in. to much?


Anybodys iunput will be appreciated

 

The 3 inch might work fine. Why not mark the pipe and have an exhaust shop bend it alot cheaper than buying one already made.

The flex part is to help with the flex of the engine.So this way it doesn't crack and break the exhaust pipe.

 

The rule of thumb that I've heard...
2 1/2 inch diameter exhausts will work fine up to around 250 hp. 3 inch, if you have plans to reach 300 hp someday.

If you don't have any clearance problems -- driving over speedbumps -- then I would go with 3 inch.

You can buy flanges here...
http://www.turbo-performance.com/Pro...ll_flanges.htm
http://www.hahnracecraft.com/hahn/parts/install.htm
http://www.roadraceengineering.com/f...andgaskets.htm

You can buy pre-bent mandrel bends here...
http://www.roadraceengineering.com/mandrelbends.htm
http://www.jcwhitney.com/webapp/wcs/...&storeId=10101
http://www.4customexhaust.com/components.htm
http://www.hedman.com/

Muffler ideas here...
http://www.flopro.com/FloPro.htm
http://www.precisionkelowna.com/exhaust-flopro.html
The Flo-Pro muffler has proven itself to beat the competition with a louvered pipe design, which accelerates the exhaust flow through the muffler. The louvers also give you a deep performance sound without the use of fiberglass that eventually blows out. The Flo-Pro mufflers are also designed to boost the horsepower generated from your vehicle.

Dynomax, WLK-17223
http://store.summitracing.com/partde...rt=WLK%2D17223

Borla
http://www.borla.com/welcome/

Hooker Aero Chamber
http://www.jegs.com/cgi-bin/ncommerc...60&prmenbr=361
http://store.summitracing.com/defaul...4922711+300044

High-flow cat converters here...
Catco at Summit
http://store.summitracing.com/
Dynamax
http://www.discountconverter.com/
http://www.randomtechnology.com/

Catco and Random Technology High-flow cats are not ODB-II compliant in California.

Dynamax appears to be ODB-II compliant...
http://www.discountconverter.com/news/obdii.htm
Many sellers of converters over the internet DO NOT USE OBD II compliant converters...so buyer beware!! Discount Converters, Ltd uses only OBD II approved converters in all so designated vehicles.

Magnaflow has introduced a new series of ODB-II compliant cat-converters.
http://www.magnaflow.com/02product/02converters.asp
Car Sound Exhaust System, LLC., the parent company of MagnaFlow Performance Exhaust is a world leader in the manufacturing of automotive catalytic converters. The production and design techniques of our catalytic converters contribute to Car Sound’s standing as the highest quality and best-valued products on the market.

http://www.car-sound.com/catalog/universal/430.aspx
MagnaFlow's California 43000 Catalytic Converters are the first series of a new line of converters designed for use on vehicles equipped with Second Generation On-Board Diagnostic (OBDII) systems. They are designed, tested, and catalogued for specific vehicles. They are not traditional universal converters. These converters have higher efficiency than conventional strict California requirements for conversion efficiency and durability. These converters are warranted for 5 years or 50,000 miles on the converter body and 5 years on the performance of the internal catalyst, including replacement for OBDII diagnostic codes for low catalyst efficiency.

 

Do i need to worry about not having the flexible material on the downpipe that i am planing on making? Will it crack easily?

 

Im not 100% sure but you might want to put it in.

 

Yes, put in a flex pipe. It is not that expensive. The exhaust manifold already has to support the turbo. No need to have any additional stress placed upon it.