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dev
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Posted by: @pwnzor
Posted by: @dev

Magnaflow makes quality exhaust components but even they messed up on the catalytic converters for our car.

Example?

 It has been rectified by Magnaflow as I mentioned but just make sure it is not old stock as its still conceivable that  some warehouses may have kept some old ones around. Most likely you will have a good one but the point I was making  is that Magnaflow  In an attempt to make a replacement cat for our car messed up but to their credit they revised their issues and generally have great customer service.  Some of the other manufactures ones which looked exactly like Magnaflow but bought at Napa had issues. 

 Keep in mind I had to do a search for it but I have read it elsewhere on other threads so it is not an isolated case and some were pissed. 

[QUOTE="oldfriends, post: 977738, member: 12162"]

Update time.........

 

In one of my last posts about my struggle to put the Magna-Flow main cat into my wife's car, I said I would update later. Here it is.

 

First -- Magna-Flow has fixed the problems with the fitment of the unit. Ironically, they fixed it in 2010 or early 2011. However, they apparently did not take the old stock out of circulation and I ended up with the first version.

 

In some of the earliest posts on this subject, one or two folks mentioned the same fitment problems I had and said that they had complained to the factory. It would seem the factory listened and fixed the problems. After my complaints last fall they actually got ahold of a stock MR2 and test installed a unit. It fit fine. I told them that was not possible. After exchanging a bunch of pictures and engineering drawings we finally realized that I have the early version of the unit and that it indeed is NOT a direct install bolt-in unit. They proved that the modified/improved unit fits and I would agree from looking at the pictures. They did the same fixes I recommended to them as I tried to get mine to fit, they just had already done it before I had my problems.

 

So, if you buy a Magna-Flow replacement main cat, be sure it has an exhaust hanger prong welded to the can of the catalytic converter. My early unit does not, and also has several other fitment problems with flange thickness and stuff. The easiest way to identify the improved part is to verify the presence of the metal rod/prong thing welded to the converter case. That mounting thing will line up with the rubber donut support on the body of the car above the cat converter location.

 

Even with the mounting difficulties my older version unit has worked fine since installed. If you are just buying one now, make sure it is the new version. If you already have the older version, you should be fine once you get it to mount up. I discussed what it takes to mount the older version properly a page or two ago in this thread. If you can get an older version at a discount, take it and use my mounting suggestions to get it to fit and you should be in business.

 

By the way, in discussion with their tech folks it was mentioned that this is a better and higher flow unit than the stock converter. I would presume the high flow part of that would mean a bit more ponies from the engine. I cannot feel a significant difference, but do think there is a tad more pep and a slightly more robust exhaust tone, but only slightly on both counts. With the exception of that aftermarket main cat, the car is totally stock, including the balance of the exhaust system. Added note -- I did gut the pre-cats while I had the exhaust system apart, so perhaps the increase in pep and improvement in sound is due to the gutted pre-cats rather than the different main cat. Dunno.

https://www.spyderchat.com/threads/magnaflow-cats-and-precats-now-carb-legal.55151/page-4

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Posted : November 28, 2019 10:45 am
Petrus
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...and all that ´about´a bit larger pulley to slow the for me unneccesarily dizzy spinning of the alternator somewhat 🤣 

 

@cats; I alternate (pun intended) between the top notch OEM one and a good quality decat pipe. Ditto the OEM muffler and a DIY special not-so-muffler 😉 

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Topic starter Posted : November 28, 2019 10:53 am
dev
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Posted by: @petrus

...and all that ´about´a bit larger pulley to slow the for me unneccesarily dizzy spinning of the alternator somewhat 🤣 

 

@cats; I alternate (pun intended) between the top notch OEM one and a good quality decat pipe. Ditto the OEM muffler and a DIY special not-so-muffler 😉 

  I have seen all kinds of aftermarket downpipes and have used a few myself.  The one I felt came closest in quality to the original in fitment was the second version of the JNZ downpipe where the flange was cut precisely  using a water jet.  It was also the one that yielded the most power and it was real power that you could feel but I had to get rid of mine because it was way too loud.  

 If you want actual power without having to lower the reliability or do anything complicated like cams, ECU and other stuff  a downpipe is the best option and its often overlooked for its significant gains.  Its also saves a good deal of weight.   

 

 

 

 

 

 

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Posted : November 28, 2019 11:08 am
pwnzor
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Based on your post above, I'm betting I get the older version of the cat pipe.  The picture on their website does not have the hanger on the cat.  That being said, Ken is the kind of guy who can make things fit, make them work, and the person who posted that did say the pipe itself is fine - once you get it to fit.

I emailed Ken to ask him to look at it and sent him a picture of the pipe directly from Magnaflow's website.

 

24065 fa450cd7 7540 402e a6bf f0174add963c 750x

http://zero3nine.com/files/dospwn.gif

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Posted : November 28, 2019 3:57 pm
Petrus
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Posted by: @dev

 If you want actual power without having to lower the reliability or do anything complicated like cams, ECU and other stuff  a downpipe is the best option and its often overlooked for its significant gains.  Its also saves a good deal of weight.   

Quite.

I have a reasonably ok decat header to a very good fitting, well made downpipe matched up to the OEM muffler head pipe welded to an enduro motorbike aluminium damper welded to an end pipe. The post cat O2 sensor is on an extension on the downpipe plug.

It lets the engine flow noticeably better. Especially where from some 5k revs the standard set up starts working to flush the exhaust gases it now gets like a third wind. With the OEM  inlet side optimised the head/bore x stroke are now the bottleneck. Different cams would do next to nothing.

Yes it is too loud. However, because the engine is só sweet and flexible, you can easily drive it about through urbanised areas without scandalising anyone. The gas pedal really is the loud pedal now. 

And yes, the weight saving makes you smíle! Downpipe & muffler now weigh in under 6 kilos. 

 

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Topic starter Posted : November 28, 2019 4:07 pm
dev
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Posted by: @pwnzor

Based on your post above, I'm betting I get the older version of the cat pipe.  The picture on their website does not have the hanger on the cat.  That being said, Ken is the kind of guy who can make things fit, make them work, and the person who posted that did say the pipe itself is fine - once you get it to fit.

I emailed Ken to ask him to look at it and sent him a picture of the pipe directly from Magnaflow's website.

 

24065 fa450cd7 7540 402e a6bf f0174add963c 750x

The picture on MWR website  is probably old and not updated. You are probably getting the new version but if you do get the old version I would exchange it  for the new one.  The guy who got it to fit needed a work around. This is the case with most downpipes or most aftermarket parts because they are not the same quality as the OEM.  However it doesn’t need to be the same quality if there are work arounds and you can save some money and possibly have improved performance but it requires some effort by the end user.   Sometimes machining is required and it can cost almost half  of what the downpipe costs in labor to fix. 

I pretty much have the worst downpipe with terrible fittings on both ends but after lots of frustration from trial and error from leaking and blown out gaskets I made it work by welding a tube on one end and then using a specialized gasket and high temp thread locker on the other.  After all that I finally have something that makes horsepower and is light weight with a good flex section but I had to work for it.  This is not something I would recommend to anyone unless they knew an exhaust guy.  

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Posted : November 28, 2019 4:54 pm
dev
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Posted by: @petrus
Posted by: @dev

 If you want actual power without having to lower the reliability or do anything complicated like cams, ECU and other stuff  a downpipe is the best option and its often overlooked for its significant gains.  Its also saves a good deal of weight.   

Quite.

I have a reasonably ok decat header to a very good fitting, well made downpipe matched up to the OEM muffler head pipe welded to an enduro motorbike aluminium damper welded to an end pipe. The post cat O2 sensor is on an extension on the downpipe plug.

It lets the engine flow noticeably better. Especially where from some 5k revs the standard set up starts working to flush the exhaust gases it now gets like a third wind. With the OEM  inlet side optimised the head/bore x stroke are now the bottleneck. Different cams would do next to nothing.

Yes it is too loud. However, because the engine is só sweet and flexible, you can easily drive it about through urbanised areas without scandalising anyone. The gas pedal really is the loud pedal now. 

And yes, the weight saving makes you smíle! Downpipe & muffler now weigh in under 6 kilos. 

 

The OEM downpipe is the bottleneck of the 1ZZ engine.  People believe it’s the intake or exhaust manifold  and it’s not. There are 1” chokes in the flex section for nose reduction that once eliminated can free up power and if the pipe diameter is increased it makes for significant gains as much as 10hp if not more. It’s sad because there are all kinds of stupid intakes for this car that do nothing and only a handful of bad fitting downpipes with cats that expire early.  

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Posted : November 28, 2019 5:09 pm
Petrus
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I have taken the duct out of the rear panel, made a bellmouth on the OEM tapered elbow and fit a TwinAir filter element.

The OEM elbow is now a restriction but swapping it for a TRD type (bell mouth is important) makes the engine less flexible and I appreciate that more than some more horses. The increase of a free exhaust is probably more than 10 hp looking at dyno graphs of other cars.  I mean if a cold-air-intake with 2.5" sports cat/muffler makes close to 160 hp, a not messed up intake with better flowing exhaust  should make at least the same no? The number is academic though. I hardly ever rev the daylights out of it anyway; 6k is my self imposed limit.  On the mountain roads the corners and road conditions are the limits, not the engine output. I freed up the exhaust not for more power but for better responsiveness and more linear revving through the range.

MR2Diffuser

Here´s a photo of the downpipe under the car*. The flexi and 2-1 bit is not as blued as the bend. Despite being more cooled the not all that tight bend gets hottest of the whole thing.

* with the cat gone, the nappy did not make any sense anymore.

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Topic starter Posted : November 28, 2019 6:56 pm
dev
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From everything I have seen. Most modified intakes for the 1ZZ  make zero horsepower and some can actually make less than stock.  
Exhaust mufflers  don’t make much of anything except for weight reduction and sound.  Only the downpipe can make 8-10 real honest to goodness horsepower. Power FC and cams can make a few more but  160hp is actually 2ZZ territory and there is no 1ZZ that has shown 160hp without major modifications stressing the engine to where it’s unreliable. 
There where a few that claimed they were fast as a 2ZZ and when asked how they came to that number they started adding up advertising hp claims.  

The 1ZZ is a dead end until you go forced induction.  The 2ZZ on the other hand responds a bit better to bolt ons but the best engine for bolt ons  is the K20.  

 

 

 

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Posted : November 28, 2019 7:39 pm
Petrus
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Posted by: @dev

There where a few that claimed they were fast as a 2ZZ and when asked how they came to that number they started adding up advertising hp claims.  

 

On the UK forum there are a few threads where dyno graphs together with the mods are collected. They make for  interesting and largely coherent reading.

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Topic starter Posted : November 28, 2019 8:13 pm
dev
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It also depends on the dyno used and the operator.  There are some shops that have been know to fudge the numbers. Then there are those that use apps to claim hp numbers.  
The ones that was mostly consistent are those that did before and after runs on the same dyno and have logged the difference between mods.  Some take the best out of four  which skews the aggregate and some just lie to make the customer happy. There have been instances where someone advertised their built engine showing their dyno and after the new owner deicides to get a new tune it is found out the car in question has much less power.  
The biggest disappointments are those that dump ridiculous sums of money in a built 1ZZ only to have little to nothing. 

The only real option is a small turbo and conservative tune for a 1ZZ or ditch the 1ZZ and swap in a 2ZZ. Most everything on a 1ZZ ends up being poor value the deeper you go.  
It doesn’t mean the 1ZZ is a bad engine just don’t mess with it and enjoy it. Toyota all ready did a good job with it to maximize power. 

 

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Posted : November 28, 2019 8:51 pm
pwnzor
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Intake, exhaust, down pipe... couple of pulleys and a water pump.  That's as far as I'll be going with this motor.

I dumped all my upgrade money into the suspension, and have been very happy with the results.  I simply never have to slow down the car unless I choose to.

4th gear at 4000 rpm and I own the corners.

http://zero3nine.com/files/dospwn.gif

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Posted : November 29, 2019 7:54 am
Petrus
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Posted by: @pwnzor

 I simply never have to slow down the car unless I choose to. 4th gear at 4000 rpm and I own the corners.

Not a lot of thát over here*. Mostly second and third with short bouts in 4th on the rare straitish connecting bits  😉 

* both the north and south slopes of the mountain range that runs from the Sierra de Grazalema in the west to beyond the Desierto de Tabernas in the east.

 

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Topic starter Posted : November 29, 2019 9:16 am
dev
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I would say dumping the most amount of money on a researched set of coilovers is the best value for this car period.  Next would be a good set of adjustable sway bars to dial in the cars behavior at the limit and then a good set of tires in near stock sizes.  

That is the recipe for fun.  Engine mods are all ways poor value for this car.  Skimping out on dampers and getting one of the cheap Chinese brands ruins the car completely. Lots of bad choices out there and some just don’t get that they are making their car worse than where they started thinking stiffness equals better handling.  

 

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Posted : November 29, 2019 9:17 am
pwnzor
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I went to OTP and checked my downpipe, it's got the hanger and was manufactured earlier this year.

I think I'm in good shape.  

As for suspension bits, I got the DGR coilovers, Battle Version control arms, polyurethane bushings everywhere they belong, and Phat's mid brace.

IMG 20190903 182616885
IMG 20190903 182545917
IMG 20190220 191453192
IMG 20190220 191517589

 

http://zero3nine.com/files/dospwn.gif

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Posted : November 29, 2019 2:59 pm
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