Downpipes

[dhirm5]

Originally Posted by greentrbo95gst

It only works for radiation of heat in the engine bay, but I am not sure if the car would generate any more heat than stock since stock turbos are remaining intact. Usually EGT- Exhaust Gas Temp is what we should be concerned with, but the only way to control it is by tuning (amount of boost, ignition timing and fuel).

Right - but I've seen a few threads regarding heat soak in these cars - a heat wrap and/or ceramic coat should help reduce that - no?

Originally Posted by greentrbo95gst

http://www.fftec.com/
Here is the shop I have been working with since mid 90's.
They recently fabricated exhaust manifolds, downpipes and built the turbo kit for the most powerful 335i in the world.
http://www.fftec.com/item/390/BMW_N5...Turbo_Kit.html

http://www.fftec.com/item/33/FFTEC_M...Turbo_Kit.html

Definitely can't argue with the quality of welds.

They attend a lot of the shifts3ctor events with the car

Nice - sounds like a competent shop. I hope we're able to work something out with them - this is getting damn interesting.

Originally Posted by greentrbo95gst

LOL, isn't it true though?

Without question.

I don't begrudge any of these vendors making money off people willing to part with it - supply and demand - but that doesn't mean some of us can't choose to go a different, perfectly legitimate, route.

[greentrbo95gst]

Would love to hear opinions from engineers on the heat soak part.
So, when the car is sucking in hot air and pushing it to the turbo, the ecu pulls timing hence the car feels more sluggish.
Now, the downpipes are behind the turbos and with heat wrap or coating it lowers back engine bay temperatures, but I don't think it reduces heat soak. Could be wrong.
It would be intresting to see some shops chime in here.

[dhirm5]

Originally Posted by greentrbo95gst

Now, the downpipes are behind the turbos and with heat wrap or coating it lowers back engine bay temperatures, but I don't think it reduces heat soak. Could be wrong.

It seems to me that reducing engine bay temps would def alleviate heat related performance degradation - whether the proper term for this particular phenomenon is heat soak or not I can't say.

i.e. http://f10.m5post.com/forums/showthread.php?t=865969

Originally Posted by greentrbo95gst

It would be intresting to see some shops chime in here.

Not likely...

[delano]

I'm not sure if you guys have seen the video with the Switzer Tuned M5 racing the M5 with the "custom" downpipes, but a tuner that knows the guy with the black car said the it doesn't run right and boggs down about 30% of the time with the DPs.

http://www.youtube.com/watch?feature...&v=cvHHoBrwtoI

They thought it was cause it needed a tune for the DPs to work right but plenty of you have the AMS without a tune and Ive heard they run fine. As the biggest performance enhancing mod available right now, Id spend the extra cash. You never know whos going to roll up on you to see what your made of and I wouldn't run the risk of dumping out cause my car isn't running right lol!

[greentrbo95gst]

Didn't know Dave's car boggs

[Vic55]

Originally Posted by delano

I'm not sure if you guys have seen the video with the Switzer Tuned M5 racing the M5 with the "custom" downpipes, but a tuner that knows the guy with the black car said the it doesn't run right and boggs down about 30% of the time with the DPs.

http://www.youtube.com/watch?feature...&v=cvHHoBrwtoI

They thought it was cause it needed a tune for the DPs to work right but plenty of you have the AMS without a tune and Ive heard they run fine. As the biggest performance enhancing mod available right now, Id spend the extra cash. You never know whos going to roll up on you to see what your made of and I wouldn't run the risk of dumping out cause my car isn't running right lol!

Hilarious, I know the owners of both cars personally and they are both well know members here and already posted the vids a while back.... Dave and Niko both have never said anything about Dave's car bogging.

Do a search for RPIM5 and you will not only see the posts on the vid but also his posts on his car after he did the down pipes.

Im not saying you should have known about this at all so dont get me wrong, but I find it so hilarious how the truth twists.

[dhirm5]

Originally Posted by delano

I'm not sure if you guys have seen the video with the Switzer Tuned M5 racing the M5 with the "custom" downpipes, but a tuner that knows the guy with the black car said the it doesn't run right and boggs down about 30% of the time with the DPs.

RPiM5 right - aka BMWDave? I hadn't heard of any bogging issues with his car.

If this is true, he might want to consider adding microcats to remove the CEL - who knows what the car does when it thinks the cats aren't working.

[greentrbo95gst]

Originally Posted by dhirm5

RPiM5 right - aka BMWDave? I hadn't heard of any bogging issues with his car.

If this is true, he might want to consider adding microcats to remove the CEL - who knows what the car does when it thinks the cats aren't working.

The car runs rich to compensate for more airflow.

[M54ccibo]

Originally Posted by dhirm5

RPiM5 right - aka BMWDave? I hadn't heard of any bogging issues with his car.

If this is true, he might want to consider adding microcats to remove the CEL - who knows what the car does when it thinks the cats aren't working.

You hit the nail on the head. The DME does a bunch when the cats are not there.

The DME believes the cat is fouled or going bad. Since the DME finds no delta between the two sensors it starts adjusting. Could be doing more, who knows. But there have been misfires.

RE: Dave's car he is the only catless car with straight pipes that I am aware of. IMHO, there are many variables at play. Can also say I have driven Dave's car and didn't experience any "bog" and he certainly didn't exhibit that when we did our 1-1 pulls.

Probably best to let Dave give all of us the full story on the history of the downpipes in his car and how the car is performing now.

[M54ccibo]

Originally Posted by greentrbo95gst

The car runs rich to compensate for more airflow.

Bingo. Lots more airflow. Potentially so much the DME is outside of its ability to adjust?

[dhirm5]

Originally Posted by greentrbo95gst

The car runs rich to compensate for more airflow.

Which I believe could result in symptoms that some might call bogging...

[greentrbo95gst]

Bingo to both of you.

[delano]

Sorry If I said something I shouldn't, I'm not trying to bad mouth someones setup. I just thought what I was told was relevant to the topic, maybe he had his facts wrong.

[M54ccibo]

Originally Posted by delano

Sorry If I said something I shouldn't, I'm not trying to bad mouth someones setup. I just thought what I was told was relevant to the topic, maybe he had his facts wrong.

No offense taken

Like Vic said, Dave is very active on the boards and I am sure he'll be around to give us info regarding this. I posted what I know, but it is not my car!

[noushy]

Well keep us posted on your results. I got a good price through my parts supplier and IND and I am not complaining. My car runs perfectly with no bogging, no CEL, no fumes and no misfires. I have factory original O2 sensors from a Z4 with longer wires and a connector swap. If you can build one of comparable quality keep us posted and make some money doing it.

Noushy

[M54ccibo]

Originally Posted by noushy

Well keep us posted on your results. I got a good price through my parts supplier and IND and I am not complaining. My car runs perfectly with no bogging, no CEL, no fumes and no misfires. I have factory original O2 sensors from a Z4 with longer wires and a connector swap. If you can build one of comparable quality keep us posted and make some money doing it.

Noushy

You went catted, correct? Any way you can measure the dB level on the car? I want to do this, but at the same time I don't want to get black flagged when I track the beast (infrequently, but I will).

[noushy]

I have an Akra exhaust but I think it still is legal. Have to dig up my old sound meter. PM me and I will dig it up.

Noushy

[M54ccibo]

Originally Posted by noushy

I have an Akra exhaust but I think it still is legal. Have to dig up my old sound meter. PM me and I will dig it up.

Noushy

PM sent!

[delano]

So I ended up linking up with Dave last night to chop it up and we took his car for a spin, it definitely does not bogg down lol. His car sounds like a jet fighter with that exhaust and it pulls like a beast!

For the record I wont be quoting rumors on here anymore

[M54ccibo]

Originally Posted by delano

So I ended up linking up with Dave last night to chop it up and we took his car for a spin, it definitely does not bogg down lol. His car sounds like a jet fighter with that exhaust and it pulls like a beast!

For the record I wont be quoting rumors on here anymore

[greentrbo95gst]

Getting ready to do the downpipe swap on the car and popped off the plastic cover today. Anyone attempted to do it themselves? It doesnt look too bad.

[ImpetuousRacer]

I'd be interested to know what's involved as well. Also, does anyone know the standard rate for professional install?