Any member using the Doug thorley 451 header?

[SCHMART]

anyone using the 451 thorley header?

Edited June 19, 2008 by SCHMART

[denisjolicoeur]

I plan on getting one soon. It looks like it gives almost a 20% improvement of torque, right where it's needed and used the most (between 2,000 and 3000 rpms). And people are reporting anywhere from 3 to 7 mpg improvement in mileage.ps. it's not actually a header, it's a cat-back exhaust pipe & muffler. It's just made by "Doug Thorley Headers"

[SCHMART]

thanks..can't wait to hear more reviews from actual users.

[LittleYellow]

http://www.451s.com/forum/topic/show?id=19...3ATopic%3A31730

Doug Thorley Stainless Steel Exhaust (451)

In stock and ready to ship. Sounds great and alot lighter than the stock muffler. ALOT! See Dyno Spec sheet for performance gains. Please call Paul at 512-244-1491. Thanks.

__________________

I can't insert graphics here so visit the link above.

I think I'm liking this one!

[RussBarnes]

I've had mine for about 1000 miles. It has gotten a little quieter, but I would like a little more and Doug Thorley is working on a tip for that. I believe it has made a significant improvement in mpg, but since I installed it has been hot here and I need AC which has kept me from doing as great as the potential.I put larger tires on that slowed my acceleration, but the exhaust overcame that with the added low end torque. It's fun and you can feel the improvement.

[LittleYellow]

You powder coated your wheels! I like it!I've been looking at custom wheels but they're hard to find without using adapters or stand-offs. *sigh*The wife and I are going back and forth about powder coating. She likes the wheels as they are. I want to do yellow spokes with either black or silver "rim". The discussion continues... lolSince we just got our smart (with extended warranty) I'm squirrely about changes like exhaust and wheels. So I'll have to check on how that effects coverage. Or just wait awhile until I'm comfortable with how the car holds up and just do it anyway. It's hard to pass on lighter wheels and better fuel economy.I was looking at XXR 003 wheels in gun metal. When I called the lady politely said "Oh, we don't have anything for the smart." Guess I might have to look into the European connection...

[MikeT]

For wheels, I would recommend choosing a set of the European market pulse wheels, which have the proper offsets, and are OEM smart equipment for the front and rear axles respectively. That way, a warranty issue (wheel bearing wear, for example) would likely not be a problem, and if it was, it should be covered.

This was the case for my car; I got a new RF wheel bearing under warranty in Year 4 despite the fact that I had wider wheels and tires than the Canadian cars came with. My wide wheels are OEM smart parts.

If I had been running non-OEM wheels or even OEM wheels with incorrect offsets on one or the other axle, I think it might have turned out differently.

[mcdnjim]

I'd check with one of the smart part sellers we have on this site first to see if they can help you out. Our Pres Smartieparts, or Fast Eddy are both in BC so not too far to ship.

[mcdnjim]

When, if you get it you might want to check out the air intake that Smartieparts and Jibber have put in seems to increase the HP and the sounds.

[RussBarnes]

I took my exhaust off and sold it, back to stock. Just didn't like the noise and Doug Thorley didn't seem to want to make an aftermarket stinger to quiet it. I have heard their new dual tip is quieter, but I've already thrown a couple hundred down this drain and figure stock will do. As to mpg and driving, hard to tell the difference. At Interstate speed the engine is the same hp so same fuel flow. Under acceleration and about 2000 there is a difference, but after watching my ScanGauge I really can't cruise at that speed and pass through it so fast that I just don't think it helped. What it did do was teach me to have a light foot so that I didn't have to hear it.

[SmartieParts]

I've had the Doug Thorley Cat Back on my car for about a week. I'm not sure what I think of it yet. Like Russ above... not sure I like the noise. I mean, at first I loved it. Sounded like people were going to turn heads when I pulled up. But the only comments I've gotten so far are things like "sounds like you have a hole in your muffler already!". The smart is a rather noisy car as it is on the highway, and I must admit I wasn't too thrilled with the extra noise after doing 3+ hours at 120kph steady.Will I go back? Well, I don't know about that either.Because one thing I can attest to is that the car certainly has more power getting over the mountains. I didn't really notice it anywhere else, and I might even say the power "feels" LESS at lower speeds (could be my imagination). I plan on testing it with a Gtech the same way I did the performance air intakes.So I may have a slightly used DT for sale... may not... undecided so far. To those that like low rumbly noise though... this might be just the ticket.Incidentally, its different than the noise the intake makes. That only comes on when you're really booking it. Not noticeable, in my opinion, during normal driving. That's the difference... the DT is present all the time. - Steven

[Guest Snapdragon]

Smartie, if you sell it, I will take it off your hands - guaranteed sale. I probably won't order one until at least the end of the month so let me know.I am used to the noise and actually MISS it. When modding my Neons I always had larger throttle bodies with large intakes and high flowing cats and mufflers, so noise is nothing new to me. Blipping the throttle on a 70mm TB and watching people turn around and look for the V8 is amusing.

[SmartieParts]

I probably will sell it. Unfortunately, I didn't watch the installation so I have to get my hands on some instructions to remove it. I can definately see why people would like it! I did for a bit, but I think now it just annoys me. I've never been into noisy exhausts though. - Steven

[Guest Snapdragon]

I've seen some instructions posted up, was either here or on the DT site. Seems pretty easy, you just need some E sockets. Shoot me a PM when you are ready to get her gone.

[denisjolicoeur]

see attachments

Doug_Thorley_INST.pdf

Doug_Thorley_exhaust_install_notes_from_other_forum_members.doc

[SmartieParts]

Cool, thanks.So yeah, I'll probably take it off when I get a chance and sell it to Snapdragon. Its a cool sound to be sure... but it didn't take long to really just be on my nerves. The intake sound I like better because its only there when you're really "given 'er" - Steven

[SylenThunder]

Just got mine in a couple of days ago... will be installing it Sunday. I'll try to take some good recordings of before and after for noise comparison.

[SylenThunder]

Got it installed Sunday. Sounds awesome. Not nearly as loud as I was afraid of, and the drone is not bad at all. Have recorded comparisons with my HD pocket recorder and will link them somewhere as soon as I can get them uploaded.

Pics are available here.

[denisjolicoeur]

Pics are available here.

I was taking a look at your pics and found the intake interesting. How did you seal the holes where the baffles were? With the intake mod alone, had you noticed any difference in performance or fuel consumption?Do you have a scanguage? Do you know how the intake air temperatures compare to stock?

[SmartieParts]

That kind of intake mod is going to have more of a moisture intake problem than the ones hanging down. Gravity is a much more consistent performer than vacuum. I just say this because people were worried about the ones that hang down too far, but they've been proven dry unless you are in water so deep that the filters are 100% covered by the water (then suction really works! It becomes a straw). But the way that one is, if there is any road water thrown up around there it is going to run back in regardless of suction. I mean... you're probably ok. I'm just saying that the only reason I can of why you did what you did was to avoid moisture, but in my estimation you've increased the probability, not decreased it. Remote either way. - Steven

[SylenThunder]

Q: How did you seal the holes where the baffles were?

A: Wrapped them really tight with some good rubber tape.

Q: With the intake mod alone, had you noticed any difference in performance or fuel consumption?

A: Not as much as I had expected. it does get a bit of a boost in for a minute before the engine warms up, and then iy drops off again. Overall the hp/tourque gain is relatively small, I mainly put it on to increase available airflow for when I put the exhaust on. I do not know how much difference it made with the exhaust on, because i haven't compared with the DTH on a stock intake.

As for fuel consumption, the difference was less than I expected it to be. I had thought that with taking in warm ait from the engine compartment that it would increase it more, but I only saw a minor, (1-2mpg), improvement. It may have been better, but it's hard to keep the foor off the pedal when it makes that cool noise at WOT.

Q: Do you have a scanguage?

A: I wish... that will have to wait for another day... just spent my free money on the exhaust and the Belle Isle meet.

Q: Do you know how the intake air temperatures compare to stock?

A: Haven't tested the intake temps, but I am almost certain that they are higher with this setup. I did leave the hose from the intake scoop, but don't think that it makes enough of a difference to matter.

That kind of intake mod is going to have more of a moisture intake problem than the ones hanging down. Gravity is a much more consistent performer than vacuum. I just say this because people were worried about the ones that hang down too far, but they've been proven dry unless you are in water so deep that the filters are 100% covered by the water (then suction really works! It becomes a straw). But the way that one is, if there is any road water thrown up around there it is going to run back in regardless of suction. I mean... you're probably ok. I'm just saying that the only reason I can of why you did what you did was to avoid moisture, but in my estimation you've increased the probability, not decreased it. Remote either way.

- Steven

Actually did a bit of testing with the water, (I have done several custom intakes, and do a lot of water testing with them because of my designs. ) I did not get any water into the intake tube. Yes, it is more likelybecause of the horizontal, but the filter would have to get quite soaked, and even when simulating some extremely severe rain showers, it did not get a significant amount of moisture on the filter, and there was no moisture in the intake tube. I feel pretty safe about it, and if the rain is heavy enough I won't be driving the smart anyhow, I'll be in the heavier SUV.

In any case... this is just temporary until K&N makes a filter specifically for the 451, rather than taking a chance with one that 'almost' fits. When that happens I plan on going with the K&N in the stock box and one of the intake scoops. Been trying to work on a ram air design that has the filter in the front, but so far the piping is so restrictive that it negates any possible gains.

Edited September 1, 2008 by SylenThunder

[SmartieParts]

Cool. Looks like you put a lot of thought into it! - Steven

[SylenThunder]

finally got a good tank of gas where I wasn't throttling it all the time.... MPG did not change. Getting about the same as I did before. It will be a few more tanks before I get a better estimate, but as far as I can see right now it hasn't changed. I think this is largely because of the intake configuration. Soon I will order the new filter, and the intake scoop from Breathless Performance and that will probably get better readings. I think I'm going to put the stock intake back in in a couple of days for a comparison.

[MikeT]

I've got to say, that noise is vulgar. If I was 19 I would dig it, but from 20 on it's gross.

[denisjolicoeur]

I dunno. Like other Smart drivers, I'm torn on the noise vs. power, but I can't even hear the intake sound anymore which is much 'cooler' than the exhaust ever could be.

That's normal with any vehicle, same thing happened with 2 trucks I owned. In both cases, I got K&N FIPK Kits first and loved the sound but then couldn't hear it when I opened up the exhaust. It's not necessarily because the exhaust is overly loud, wasn't with the trucks anyways, but it's simply the exact same tone.