Any interest in Crucial Downpipe?
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Crucial Racing
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Well cool. Thanks for the kind words and whatnot, guys 
We do hear back from tuners fairly often about how surprised they were after tuning cars with our downpipe on them. The divorced wastegate design works extremely well, and it's very apparent to tuners in the ease of tuning the boost control, the great boost/throttle response, and the very strong power/tq output. Most tuners say that tuning the boost curve via wastegate duty cycles throughout the powerband takes longer than tuning the A/F curves and the timing curves. With our downpipe there is just much less tinkering necessary as the atmosphere into which the wastegate vents is always constant. With a bellmouth, it's constantly changing with the amount of exhaust coming out of the turbine outlet, so the wastegate vents differently depending on load and rpm, etc. A couple tuners said it was like tuning with an MBC in terms of simplicity and awesome response. So.... we'll take it
^^^ before I move on, btw, if you read Corky Bell's book, Maximum Boost, he talks about wastegates and very bluntly mentions the power and tunability benefits of separating the wastegate gasses as much as possible. Our downpipe is pretty much the extent of what you can do with an internally-gated turbo. The place you don't want turbulence is right before or right after the turbine... so moving the WG pipe down towards the bottom of the downpipe is far enough down the exhaust stream that it doesn't affect the function of the turbo, turbine outlet, or wastegate at that point.
So ANYWAY... it sounds a lot like our existing downpipe would work and we'd just have to do a custom midpipe to work on the BC-BF Legacy and allow the use of a stock-length catback. We could also do a full-length downpipe if you guys decided you didn't want it modular. If people are on a budget, we can get it made with a bellmouth and full length at a very good price.
Basically, y'all will have to come to a general consensus on what style you would like. I would want to get my hands on a stock BC-BF downpipe with midpipe attached so we can make an accurate JIG from which to build the production ones.
Our WRX downpipe is available with an auxiliary O2 bung in it, but the stock WRX bung is in the midpipe by the cat. If you guys needed two in the downpipe and none in the midpipe, that's not a problem. It'll all just have to get figured out.
For simplicity's sake I'd almost just want to have a full length bellmouth made. We can get them in that style and thermal barrier coat them and have them at a very very competitive price. I do sort of feel that nearly everyone will have to get a custom catback made to flow the kind of exhaust you might be making (as I have done a couple times in my EJ20-swapped '98 Legacy GT) so having the downpipe/midpipe end exactly where the stock one does doesn't really seem like a big issue, honestly. Everyone's sure the WRX ones actually need to be changed beyond moving O2 bungs, etc?
Jeremy
btw -- this is how our downpipe seals up with nearly all of the bolt-on turbos for our cars. It's really the design if you want the least possible amount of turbulence behind the turbine outlet. This picture is a VF39 turbine housing and you're looking from the side where the downpipe would normally be... this is just a mock-up flange with no pipe attached. You can see why we go from 2.5" smoothly to 3"... 2.5" matches the curvature of bolt-on turbos perfectly and is much larger than the actual turbine diameter of even the largest stock-location turbos.
...and a picture from Hugh MacInnes' Turbochargers just cuz
We do hear back from tuners fairly often about how surprised they were after tuning cars with our downpipe on them. The divorced wastegate design works extremely well, and it's very apparent to tuners in the ease of tuning the boost control, the great boost/throttle response, and the very strong power/tq output. Most tuners say that tuning the boost curve via wastegate duty cycles throughout the powerband takes longer than tuning the A/F curves and the timing curves. With our downpipe there is just much less tinkering necessary as the atmosphere into which the wastegate vents is always constant. With a bellmouth, it's constantly changing with the amount of exhaust coming out of the turbine outlet, so the wastegate vents differently depending on load and rpm, etc. A couple tuners said it was like tuning with an MBC in terms of simplicity and awesome response. So.... we'll take it
^^^ before I move on, btw, if you read Corky Bell's book, Maximum Boost, he talks about wastegates and very bluntly mentions the power and tunability benefits of separating the wastegate gasses as much as possible. Our downpipe is pretty much the extent of what you can do with an internally-gated turbo. The place you don't want turbulence is right before or right after the turbine... so moving the WG pipe down towards the bottom of the downpipe is far enough down the exhaust stream that it doesn't affect the function of the turbo, turbine outlet, or wastegate at that point.
So ANYWAY... it sounds a lot like our existing downpipe would work and we'd just have to do a custom midpipe to work on the BC-BF Legacy and allow the use of a stock-length catback. We could also do a full-length downpipe if you guys decided you didn't want it modular. If people are on a budget, we can get it made with a bellmouth and full length at a very good price.
Basically, y'all will have to come to a general consensus on what style you would like. I would want to get my hands on a stock BC-BF downpipe with midpipe attached so we can make an accurate JIG from which to build the production ones.
Our WRX downpipe is available with an auxiliary O2 bung in it, but the stock WRX bung is in the midpipe by the cat. If you guys needed two in the downpipe and none in the midpipe, that's not a problem. It'll all just have to get figured out.
For simplicity's sake I'd almost just want to have a full length bellmouth made. We can get them in that style and thermal barrier coat them and have them at a very very competitive price. I do sort of feel that nearly everyone will have to get a custom catback made to flow the kind of exhaust you might be making (as I have done a couple times in my EJ20-swapped '98 Legacy GT) so having the downpipe/midpipe end exactly where the stock one does doesn't really seem like a big issue, honestly. Everyone's sure the WRX ones actually need to be changed beyond moving O2 bungs, etc?
Jeremy
btw -- this is how our downpipe seals up with nearly all of the bolt-on turbos for our cars. It's really the design if you want the least possible amount of turbulence behind the turbine outlet. This picture is a VF39 turbine housing and you're looking from the side where the downpipe would normally be... this is just a mock-up flange with no pipe attached. You can see why we go from 2.5" smoothly to 3"... 2.5" matches the curvature of bolt-on turbos perfectly and is much larger than the actual turbine diameter of even the largest stock-location turbos.
...and a picture from Hugh MacInnes' Turbochargers just cuz
CrucialRacing@gmail.com
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tris91ricer
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Hi Jeremy,
Thanks for the reply. I dont have a good pic of the stock downpipe, but it's a one piece setup. I have no problem giving my stock downpipe for measuring and whatnot. You'd just have to wait about two to three weeks. Personally, I don't want a bellmouth setup.
Can we all decide on what size/style we want?
Divorced with 3" ending in a flat flange
Divorced with 3" ending in a donut for stock fitament
Bellmouth with 3" ending in a flat flange
Bellmouth with 3" ending in a donut for stock fitament
Something else?
Thanks for the reply. I dont have a good pic of the stock downpipe, but it's a one piece setup. I have no problem giving my stock downpipe for measuring and whatnot. You'd just have to wait about two to three weeks. Personally, I don't want a bellmouth setup.
Can we all decide on what size/style we want?
Divorced with 3" ending in a flat flange
Divorced with 3" ending in a donut for stock fitament
Bellmouth with 3" ending in a flat flange
Bellmouth with 3" ending in a donut for stock fitament
Something else?
Rio Red 90 Legacy LS AWD 174k
Liquid Silver 92 SVX LS-L 88k
[url=http://folding.amdmbpond.com/FoldingForOurFuture.html]Do you fold?[/url]
I'm on First and First. How can the same street intersect with itself? I must be at the nexus of the universe.
Liquid Silver 92 SVX LS-L 88k
[url=http://folding.amdmbpond.com/FoldingForOurFuture.html]Do you fold?[/url]
I'm on First and First. How can the same street intersect with itself? I must be at the nexus of the universe.
Comrades, +1 for **Divorced with a 3" flat flange for aftermarket/custom fit**...I mean 'hello?' after all that talk about the divorced design you think I'm going back to bellmouth!? Are you kidding?
BUT I still want the high flow cat, would that be an option with the above mentioned 'full lenght' downpipe which I'm assuming eliminates the separate mid-pipe? Please let me know...
Also, don't have an opinion on bung location (but I'm sure it's right behind me!
No, really, educate me, folks.
I am planning to do engine mods and tuning sometime in this life span but not right away...
Herr Crucial, thanks! Future customers await you!
Adam
BUT I still want the high flow cat, would that be an option with the above mentioned 'full lenght' downpipe which I'm assuming eliminates the separate mid-pipe? Please let me know...
Also, don't have an opinion on bung location (but I'm sure it's right behind me!
No, really, educate me, folks.
I am planning to do engine mods and tuning sometime in this life span but not right away...
Herr Crucial, thanks! Future customers await you!
Adam
93SS 5MT White, TD05-16G, TMIC, 3"Turboback, Magnaflow, Alu Rad, H&R Sports, AGX struts, F/R STBs, Whiteline Sways, ALK+Endlinks, Odyssey 925, AC delete, Evo8 Recaros, Sparco 4p, 3.9 LSD, Hellas+air horns, IPD short throw, 99RSrims, s03's
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Crucial Racing
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Both full length (single piece downpipe) or shorty + midpipe modular style would be doable. Consider that a T304 stainless steel flange costs close to $20 and it's clear why most companies choose to do a full length one. There will be an obvious cost difference due to the two extra flanges and also the welding on those two flanges that isn't necessary, obviously, when it's one piece.
The only downside will be the highflow cat thing. Yes, we can put one in the pipe but unfortunately that means it wont be coated... at least not internally. You can't coat a catalytic converter outside or in, so unless we pre-coated the pre-cat portion of piping before welding together it would have to get done externally only, which will most definitely still cut down on radiant heat coming off of the pipe but it wont be as effective as doing it both in and out. ...also obviously a bit on the extra complicated side as we don't actually manufacture them, we contract a company that specializes in exhaust assembly so it can be done to the kinds of standards we would like. So we'd have to get the parts bent and whatnot, coat them, send them back for assembly (welding), then get them again to send out to you dudes...
It would probably be easier to do as a two-piece system if people want highflow cats. It would allow us to make a downpipe of some length then a tiny racepipe section that could either be catless or catted. Might actually be cool if we do it as a proprietary thing where the "test pipe" portion is like 10" long and combined with the downpipe the total length is the same as your stock pre-catback piping. That little 10" portion would be really darn affordable in the catless variety, so theoretically it would be quite easy for those people who want a highflow to also purchase the racepipe and switch back and forth as desired. The metallic substrate catalytic converters are quite expensive though, so for those who wanted a catless setup they'd just get the racepipe one.
Jeremy
The only downside will be the highflow cat thing. Yes, we can put one in the pipe but unfortunately that means it wont be coated... at least not internally. You can't coat a catalytic converter outside or in, so unless we pre-coated the pre-cat portion of piping before welding together it would have to get done externally only, which will most definitely still cut down on radiant heat coming off of the pipe but it wont be as effective as doing it both in and out. ...also obviously a bit on the extra complicated side as we don't actually manufacture them, we contract a company that specializes in exhaust assembly so it can be done to the kinds of standards we would like. So we'd have to get the parts bent and whatnot, coat them, send them back for assembly (welding), then get them again to send out to you dudes...
It would probably be easier to do as a two-piece system if people want highflow cats. It would allow us to make a downpipe of some length then a tiny racepipe section that could either be catless or catted. Might actually be cool if we do it as a proprietary thing where the "test pipe" portion is like 10" long and combined with the downpipe the total length is the same as your stock pre-catback piping. That little 10" portion would be really darn affordable in the catless variety, so theoretically it would be quite easy for those people who want a highflow to also purchase the racepipe and switch back and forth as desired. The metallic substrate catalytic converters are quite expensive though, so for those who wanted a catless setup they'd just get the racepipe one.
Jeremy
CrucialRacing@gmail.com
www.CrucialRacing.com
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legacy92ej22t
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I already run a really nice divorced wastegate DP so I won't be buying one of these (but they look very nice Jeremy! ) but I have to say that I would sure hate to see you guys do anything but the divorced w/3" flat flange. Divorced is sooooo nice. I wouldn't want to run anything else.
Keep the cat seperate and then you can also have a test-pipe (3" pipe that is the same length as the cat and has the same bends) so you can run either catless or catted and switch back and forth at will. That's what I do with my CES. Then you just have to do a custome 3" catback or if Jeremy offers.......wait, I just noticed Jeremy talking about a test pipe or catted solution like I'm jabbering about in the above thread. Oops.
Good idea Jeremy!
) but I have to say that I would sure hate to see you guys do anything but the divorced w/3" flat flange. Divorced is sooooo nice. I wouldn't want to run anything else.Keep the cat seperate and then you can also have a test-pipe (3" pipe that is the same length as the cat and has the same bends) so you can run either catless or catted and switch back and forth at will. That's what I do with my CES. Then you just have to do a custome 3" catback or if Jeremy offers.......wait, I just noticed Jeremy talking about a test pipe or catted solution like I'm jabbering about in the above thread. Oops.
Good idea Jeremy!
-Matt
'92 SS 5mt. All go and no show. Sold :(
'94 Audi UrS4 Modded (new project)
'96 Outback 5mt.
'07 Legacy 2.5i SE
[quote="Redlined"]
Oh... and I hope the fucker get bunked with Gunter, arrested for raping Gorillas.[/quote]
'92 SS 5mt. All go and no show. Sold :(
'94 Audi UrS4 Modded (new project)
'96 Outback 5mt.
'07 Legacy 2.5i SE
[quote="Redlined"]
Oh... and I hope the fucker get bunked with Gunter, arrested for raping Gorillas.[/quote]
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Crucial Racing
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What's going on with this? Is Jeremy working on something for us? Who's talked to him lately. I'd love an ETA to help plan out my budget...
Last edited by Adam West on Tue Jun 13, 2006 2:16 am, edited 1 time in total.
93SS 5MT White, TD05-16G, TMIC, 3"Turboback, Magnaflow, Alu Rad, H&R Sports, AGX struts, F/R STBs, Whiteline Sways, ALK+Endlinks, Odyssey 925, AC delete, Evo8 Recaros, Sparco 4p, 3.9 LSD, Hellas+air horns, IPD short throw, 99RSrims, s03's
Okay, so we're pretty much decided that if you're buying this downpipe you'll be using a custom catback, and not the stock setup right? How about if we do a two piece design. Keep the first pipe the same length as a WRX pipe, then the second piece make it the length needed to use a WRX catback? Allow me to demonstrate with ascii!
Or something. This would allow WRX fitment and easy upgradability.
Or just a replacement stock length downpipe full 3" flat flange. Either is fine for me.
Code: Select all
Legacy Exhaust Length
DOWNPIPE-----------------CATPIPE------------------AXLEPIPE
WRX Exhaust Length
DOWNPIPE----MIDPIPE----CATPIPE----------------AXLEPIPE
Crucial Exhaust Length
CRUCDOWNPIPE--CRUCMIDPIPE--WRXCATPIPE----------WRXAXLEPIPE
Or just a replacement stock length downpipe full 3" flat flange. Either is fine for me.
Rio Red 90 Legacy LS AWD 174k
Liquid Silver 92 SVX LS-L 88k
[url=http://folding.amdmbpond.com/FoldingForOurFuture.html]Do you fold?[/url]
I'm on First and First. How can the same street intersect with itself? I must be at the nexus of the universe.
Liquid Silver 92 SVX LS-L 88k
[url=http://folding.amdmbpond.com/FoldingForOurFuture.html]Do you fold?[/url]
I'm on First and First. How can the same street intersect with itself? I must be at the nexus of the universe.
Yes, I'll be using custom catback. True. But I like what you say here...
"How about if we do a two piece design. Keep the first pipe the same length as a WRX pipe, then the second piece make it the length needed to use a WRX catback?"
+1 for that.
What about our bungs - how many and where?
Thanks T,
"How about if we do a two piece design. Keep the first pipe the same length as a WRX pipe, then the second piece make it the length needed to use a WRX catback?"
+1 for that.
What about our bungs - how many and where?
Thanks T,
93SS 5MT White, TD05-16G, TMIC, 3"Turboback, Magnaflow, Alu Rad, H&R Sports, AGX struts, F/R STBs, Whiteline Sways, ALK+Endlinks, Odyssey 925, AC delete, Evo8 Recaros, Sparco 4p, 3.9 LSD, Hellas+air horns, IPD short throw, 99RSrims, s03's