More info RJC Racing 5" DP
- Thread starter Race Jace
- Start date
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Here are some questions and answers.
Why 5”dia for 18” and then neck down to 3.5”?
Buickpower is on the right track. As the exhaust gases exit the turbo it is very critical to have as large as area as possible. This is where the gasses convert from radial to linear flow. It is explained in most any turbo charging basic book. It is only critical for around the first 15” from the turbine exit. This is why you pick up about 30 hp when switching from a 3 to a 3.5” DP even though you still retain a 3” cat back exhaust. We probably could have fit a 4” through there but we had a pre bent 3.5” DP that was an easy mod to make it complete.
Is RJC going to offer a complete DP?
Maybe eventually if we track down a source on mandrel bending. For now we are going to offer the elbow, weld flange, and intergral WG flange with the WG puck installed. This will make it a snap for the do it yourselfers.
Will this fit the ATR headers?
Yes it is possible to make one similar to the one we made (5” for 18” then kneck down to 3.5” dia) and have it fit with the ATR headers.
Why did you pick 5” and not 4” or 6”?
The largest exhaust doughnut available in that has the same centerline radius as the dia (IE 5” dia pipe with a 5” dia radius) was 5” they do not make any 6” exhaust doughnuts.
We had to use a minimum of 5” to get all of the bolts on the inside of the flange. Otherwise this would not have worked.
Are you going to make one for the 4 bolt guys?
No, you must have a 3 bolt precision housing for this to work without leaking. The garret 3 bolt housings won’t work but if you want this you probably have a “q” trim turbo anyway. We will probably make one for the large 3 bolt 88 housing when I upgrade my turbo to that one.
Is this strictly a race car piece?
No there are no downsides to this pipe. It will work fine on the street on any car that has a precision housing equipt turbo.
What is the projected price?
We are looking to keep the 3 pieces under the $400 range and the complete pipe under $600.
Is this piece legal for the class?
It is legal for vegas and BG TSM classes. All other classes we will work on making it become legal.
I hope I answered all the questions, it would be easier to sort through if you guys would refrain from the name calling and stuff
BTW 88ZNX, no one thinks you are a ricer. some guys get a little intimidated by a big pipe. j/k.
Why 5”dia for 18” and then neck down to 3.5”?
Buickpower is on the right track. As the exhaust gases exit the turbo it is very critical to have as large as area as possible. This is where the gasses convert from radial to linear flow. It is explained in most any turbo charging basic book. It is only critical for around the first 15” from the turbine exit. This is why you pick up about 30 hp when switching from a 3 to a 3.5” DP even though you still retain a 3” cat back exhaust. We probably could have fit a 4” through there but we had a pre bent 3.5” DP that was an easy mod to make it complete.
Is RJC going to offer a complete DP?
Maybe eventually if we track down a source on mandrel bending. For now we are going to offer the elbow, weld flange, and intergral WG flange with the WG puck installed. This will make it a snap for the do it yourselfers.
Will this fit the ATR headers?
Yes it is possible to make one similar to the one we made (5” for 18” then kneck down to 3.5” dia) and have it fit with the ATR headers.
Why did you pick 5” and not 4” or 6”?
The largest exhaust doughnut available in that has the same centerline radius as the dia (IE 5” dia pipe with a 5” dia radius) was 5” they do not make any 6” exhaust doughnuts.
We had to use a minimum of 5” to get all of the bolts on the inside of the flange. Otherwise this would not have worked.
Are you going to make one for the 4 bolt guys?
No, you must have a 3 bolt precision housing for this to work without leaking. The garret 3 bolt housings won’t work but if you want this you probably have a “q” trim turbo anyway. We will probably make one for the large 3 bolt 88 housing when I upgrade my turbo to that one.
Is this strictly a race car piece?
No there are no downsides to this pipe. It will work fine on the street on any car that has a precision housing equipt turbo.
What is the projected price?
We are looking to keep the 3 pieces under the $400 range and the complete pipe under $600.
Is this piece legal for the class?
It is legal for vegas and BG TSM classes. All other classes we will work on making it become legal.
I hope I answered all the questions, it would be easier to sort through if you guys would refrain from the name calling and stuff
BTW 88ZNX, no one thinks you are a ricer. some guys get a little intimidated by a big pipe. j/k.
Mike Licht
I was here first
- Joined
- May 23, 2001
- Messages
- 4,642
Race Jace said:
When I spoke to Scott about the legality of this type of unit in TSM a year or so ago when were looking at making one I was told "no". The rules were amended in fact to prevent it. I looked at the TSM rules again and this is clearly not legal for the points series? Correct?
Mike
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