see also the Pre-cat Eliminator option
I
purchased the Turbo-Back "Stan's Headers" complete system from Isuzuperformance. This system
is "complete" since it runs from the wastegate exhaust manifold
at the exit of the engine all the way back to the tailpipe! It is also
designed and built especially for the Elan--so it should just fit easily into
place.
The system comes via UPS in one big box and contains 4 components that must be installed as a unit to form the system. (see picture)
This system is no longer produced! Read on, however, for information purposes . . .
About the System
The highlight of the system is that it is constructed with 2 1/2 inch pipes all the way from the engine to the tailpipe!
Why use a bigger pipe you wonder?? Well since flow is related to resistance which is directly related to the diameter of the pipe, a larger pipe will have less resistance and allow more free-flowing of the exhaust.
How much more you wonder?? As you all know, area is related to diameter by the equation: area = Pi X radius squared. So moving from a 1 inch radius to a 1.25 inch radius gives an area 1.5625 times as large!! This is a significantly bigger area with a seeming small increase in pipe size!!
Wouldn't no exhaust be the best you are wondering now?? Well it would but it is much louder--and having those super hot gasses all shooting out in the engine bay is not a good thing!! So the function of the exhaust system is to get the hot exhaust gases away from the car in the best flowing way while allowing the mandated emissions catalytic-converter to be present!
About the Pieces
All pieces are made from "Aluminized Steel"--this is steel pipe with a thin layer of aluminum over it. It won't rust fast like your steel pre-cat, but will slowly submit to time. You can get the parts coated in a ceramic finish to better conduct the heat away from the engine, but there is an extra charge for this.
(1) The first component consists of the "Pre-cat" eliminator and downpipe with flexible joint. The Pre-cat Eliminator bolts directly to the turbo wastegate exhaust manifold and replaces the original Pre-catalytic converter.
What is a Pre-cat you ask?? Well, it is put at the start of the exhaust system to function for "cold-start emissions." As such it is smaller than the main catalytic converter and thus heats up more rapidly to become active first with regards to catalyzing the exhaust gases. Removing this part is against the emissions laws in the US. This part is therefore intended for off-road use only, and can be interchanged with your original pre-cat if you chose--the rest of the system is totally legal in every way, shape, and form. (Mine was so rusted-out that it clearly was no longer functioning much at all!)
Why eliminate the pre-cat?? Well this rusty iron trash can is the first part in the system and as installed in the Elan is a constriction to the exhaust flow! As seen in the pictures I took of it below, it starts with a 4 inch opening and immediately constricts it to a 2 inch size!! From here out the original system is all 2 inch diameter. Thus, if you are going to put larger piping in the system you must take away this constriction or you will still effectively have a 2 inch system as the resistance will still be there!!
The Flexible braided section is a luxury as well! As you know from experience or reading my downpipe write-up, this is an infamous part of the Elan which is prone to failure--the reason why is it ends up absorbing all the vibrations between the engine and the long-lever-arm exhaust which is held by rubber mounts but is still fairly rigid. Why do you think newer nice cars have since incorporated this part? This part will absorb the engine vibrations so the welded exhaust joints don't have to suffer!! Aaahhh, I like that!!
(2) The Catalytic Converter attaches next. It fits to the first pipe and goes in the same place under the car as the original one. It is a straight-thru shot and is also 2 1/2 inch diameter. This part is just a bunch of fine metal screens which work to serve as a catalyst surface area when properly heated to operating temperature. Looking at the rusting condition of my old one I can tell you the new one will work much better!! Also I would figure the new one is better designed and more efficient than a 10 year-old one.
(3) Next is a long section of 2 1/2 inch pipe that runs from the catalytic converter back to just under the center of the rear suspension where it meet up with the final pipe. It hangs, of course, in the original rubber mounts under your car!
(4) The final pipe makes the turns needed to get the new muffler in the stock position. the included muffler/silencer is from Magnaflow and you can read about its merits on their site. This is a "straight-thru" muffler and is, of course, of a 2 1/2 inch diameter and hangs in the original rubber mounts. The tail pipe was just left generic. As such you can leave it be or add your favorite style exhaust tip as desired!
There are also 3 ring-pipe clamps that come with the system for connecting the pipes together.
About Installation
Well I was going to install the system myself, but I am definitely glad I took it to an exhaust place to do the work. The system is built for the Elan so it goes into place well, but there were a few minor problems that would have made the job tough to impossible for a home mechanic like me!
Just removing the old system can be the hardest part. Getting some of those old rusted bolts out required special techniques like using a blow torch to heat the nuts up followed by cooling them and spraying with rust breaker and using some power wrenches to get them out. Also getting the parts off of and onto the rubber mounts can be difficult--and if one of the old dried cracking rubber mounts breaks you will sure want to have a replacement available like they did at the exhaust shop. The top gasket was in fine shape and was just re-used with the original nuts without a problem.
The other hassle was getting parts 3 and 4 to fit together. The female end of 4 was too small for the girth of 3 (stop that foul thinking!). This was not a problem for the shop as they just stretched the female end out a bit using their special pipe machine so the fit was proper--try this at home or by yourself!!
Also as an advantage, the shop was able to weld the exhaust joints so I don't have to worry about leaks--for a while. All this took an experienced shop 1 hour to do--how long would it have taken me?? (Forever is the answer with more swearing than a team of ballplayers!)
So the bottom line is get someone who does it for a living to install your system--you will thank yourself as I did!
System Performance
So you're wondering how it performs?? In a word, GREAT, but you know I am more verbose than that!!
Sound
I was worried about the loudness of the exhaust note, as my previous experience with a broken downpipe revealed a very loud roar! However I was never too fond of the little Cinderella exhaust sound from the stock Elan. Well I am happy to say the new exhaust note is deeper and gives the car a much nicer sports-car-sound.
It does get loud under full-throttle mid to high rev acceleration, but this is where you want it to sing for you anyway! This is where you get to enjoy the pleasures of your kick-ass engine!
Also important to me was the highway sound of the system in cruise-mode. Again I am happy to say it seems just a touch louder with the top up than stock and really is 95% the same with the top down. I have not needed to change the volume of my stereo to hear my music as I like it, and I think this tells you the most regarding the highway sound.
Yes it does have the ability to set off annoying Porsche car alarms with a gentle rev, and it certainly gives underpasses and parking structures an AIRE of your presence.
Furthermore, now having had the system in place for a while, I feel the sound to be very inherent and "normal" and can't imagine how quiet the stock system used to be. The system is definitely not loud--it is just right.
Boost Response
Very noticeable is the much improved boost response with the system installed. This has to do with the decreased resistance of the system which makes it easier for the engine to shoot out its exhaust and spin the turbo up.
For example, drive in 5th gear at highway speed and put your foot down. It will take about two or three seconds for the needle to get sufficiently up in the Fun Gauge. With the new system the boost response is very quick in this situation and is a tribute to its freer-flowing nature. It will go to near 1 bar in my car in about a second!! Yes, I too was very surprised at this but I assure you this analogy is correct. Likewise the boost response is much quicker in all situations. I have not noticed or heard any boost spikes or any exhaust surging or popping that other people seem to have reported with other set-ups.
The bottom line here is that you will have more boost response and thus more power faster when you want it!!
Power
Aaahh, Yes, I though you'd ask. Well as evidenced by the faster boost response, the engine is able to get the exhaust out of the engine better and faster. Therefore it is getting it INTO and THROUGH the engine better as well! More air going thru the engine is synonymous with more power being generated in our cars!
More evidence is that I DID have to change the setting of my MBC. The freer flow was causing my turbo to spin faster at the same wastegate setting causing more boost than before, so I was hitting the boost cut-off after installing the system. This will need to be done in Elans with adjustable wastegate jobs, but it will not affect the stock settings.
Also in all situations I tell you I can just FEEL the difference with more response and power! There are some serious bugs in my teeth again from my "perma-smile"! Even though my car is already much "enhanced" from a stock Elan, I noticed a power gain much greater than anticipated. I am amazed at the improvement gains simply by changing the system out.
Emissions
I have recently had to get another California biennial auto smog test--this is our state-mandated emissions test for you out-of-towners. The car passed all emissions subparts with the system in place and the pre-cat removed!! --Update, the car has passed yet again 2 years later !
Bottom Line: This exhaust system is great and I am glad I finally scraped up enough money to get it. I am more impressed with it than I had imagined. I'd definitely recommend it to all Elan owners. The price is not cheap but is actually very good, considering the price of comparable systems for other cars out there!! You should leave the installation to a pro.
Since this system is no longer available, others have made similar systems for
their Elans with equal success. The ultimate success of the system is due
to the Pre-cat
Eliminator--others have found that replacement exhaust systems without
pre-cat removal is good, but not near as good as with pre-cat
replacement!
Comments from other owners
of this system:
From: Matt
Title: New Exhaust
Message: Did all the preliminary work for installing the performance exhaust yesterday. Everyone said I would strip/break some of the bolts from the pre-cat, so I didn't force anything, used lots of
Rost-Off (German Liquid-Wrench) and took my time, and they all came off! Only real problem I had was with the top bolt on the heat-shield. Broke a 3/8 inch extension on that and had to remove all the plumbing off the turbo to finally get good leverage. (attacked it from the top of the car instead of the bottom). Anyway, all the hard work's done now and I can't wait until the exhaust system finally arrives, hopefully before the weekend (but probably not). Put everything back together for now after cleaning it and coating with high-temp synthetic grease. I want those bolts to just spin-off by themselves next time! Will keep you posted once I get the exhaust installed... but I can really see how restrictive the stock exhaust is now, so I am expecting great things!
Message: ...was waiting on my doorstep yesterday & I installed it last night. Took it to the welder today to weld the 3 joints. The exhaust is a bit louder than stock, but it works. The boost gauge jumps right up, even when you're in a gear that's too high, that's a big difference from the stock exhaust. I just had time last night to run up to Midas muffler and get them to expand the ends of a piece of pipe 12 inches long. Used that instead of the cat. This is probably what you Euro guys would want to do. (They didn't even charge me) One tip I would have is, don't be as exuberant to install it as I was. Exhaust studs stay hot and therefore EXPANDED longer than the nuts that are on them (the nuts are exposed to the air and so are the first things to cool down). Instead of the nut coming off, you will back out the stud. Let everything cool down before getting started.
From: Grant Schneider
Send me your comments if you own this or other systems and I will post them here for all to see. --Doug