Single Turbo Discussion Area for discussing single turbo RX-7's.

Let's Examine The Gt40

Thread Tools
 
Search this Thread
 
Old 10-15-2003 | 07:23 AM
  #21  
93 R1's Avatar
Senior Member
 
Joined: Sep 2002
Posts: 3,867
From: Maryland
Default

Originally Posted by jspecracer7' date='Oct 14 2003, 07:07 PM
nope. Half bridge with the rotor housing cut will give me more flow than a full bridge. I think I'll bridge the primary's instead of the secondaries.
????????????



Why? Never heard of that. Please explain
Old 10-15-2003 | 07:38 AM
  #22  
treceb's Avatar
to infinity & beyond, me
 
Joined: Aug 2001
Posts: 5,124
From: santurce
Default

probably to get a greater air flow at lower rpms.
Old 10-15-2003 | 07:47 AM
  #23  
jspecracer7's Avatar
Senior Member
 
Joined: May 2002
Posts: 4,928
From: Okinawa, Japan
Default

Originally Posted by 93 R1' date='Oct 15 2003, 09:23 PM
????????????



Why? Never heard of that. Please explain
well, think about this. when porting the primary ports, your limited to size because of the water jacket right? So...if you bridge the primaries, you'll get more airflow than you would a streetport. Now the secondaries...you can't make them as big as a street port because of the "bridge" that the corner rides on, where as a streetport, you don't have to worry about that as much. So now you have a half bridge(primary) with cut rotor housings flowing tons more air.



Kind of hard to explain, but in person, it's cake. IGY did it on his rotor housings and I was amazed at the power it made(at .8 kilos boost I SWORE to never ride in his car again...and I haven't)
Old 10-15-2003 | 09:21 AM
  #24  
IGY's Avatar
IGY
Senior Member
 
Joined: Dec 2001
Posts: 472
From: Okinawa Japan at McDonalds
Default

The primary bridge is a theory, the only real limitation I see is intake manifold/ primary runner size. This is why I want to try this using a cosmo center plate and intake manifold. As far as beveling the rotor housings, I was fairly sure that everyone did this unless they were following certain class rules forbidding porting on the rotor housings. I personally believe that for turbo charged rotaries that a full bridge extends the powerband to high in the rev range, and is of no benefit for the average person. 12,000 rpm's with boost is alot different than 12,000rpm's without.
Old 10-15-2003 | 12:37 PM
  #25  
93 R1's Avatar
Senior Member
 
Joined: Sep 2002
Posts: 3,867
From: Maryland
Default

I agree with you. There isn't really a need for 12,000 with 20 psi, but it does sound badass.



So why do most people bridge the secondaries, instead of primaries when doing a half bridge? Just trying to understand the logic between the 2. I had an indepth conversation with Judge Ito about this, since he will be building my half bridge. He never mentioned bridging the primaries instead......





Basically I want what IGY has. A car that will scare the **** out of people, and just put a huge smile on my face everytime I drive it. IGY what kind of power was your car making roughly?
Old 10-15-2003 | 06:14 PM
  #26  
jspecracer7's Avatar
Senior Member
 
Joined: May 2002
Posts: 4,928
From: Okinawa, Japan
Default

Originally Posted by 93 R1' date='Oct 16 2003, 02:37 AM
I agree with you. There isn't really a need for 12,000 with 20 psi, but it does sound badass.



So why do most people bridge the secondaries, instead of primaries when doing a half bridge? Just trying to understand the logic between the 2. I had an indepth conversation with Judge Ito about this, since he will be building my half bridge. He never mentioned bridging the primaries instead......





Basically I want what IGY has. A car that will scare the **** out of people, and just put a huge smile on my face everytime I drive it. IGY what kind of power was your car making roughly?
lol...your going to have a beast of a car if you want to replicate IGY's BP motor. I was destroying cars left and right when IGY was tuning it. At 1.3 kilos, even 20B's were being left in the dust
Old 10-15-2003 | 06:21 PM
  #27  
Badog's Avatar
Senior Member
 
Joined: Jul 2001
Posts: 273
From: oHIo
Default

Hmmm. You boys get back on topic....NOW!



Based on CFM calculations and VE numbers that are probably not right, I think this turbo is going to have a heck of a top BANG with a fairly decent spool up. I am most concerned with it at 17psi and around 5000rpm. Matched with the right amount of extra CFM from a large street port or a race port (the latter with more overlap between intake and exhaust....my definition for this post anyways) it will be nice. On a mild or stock port, I think you run the risk of being to left of the surge line....not enough UMPH!



Going to be a joy.....soon.
Old 10-15-2003 | 10:02 PM
  #28  
rx7tt95's Avatar
Thread Starter
Senior Member
 
Joined: Jul 2001
Posts: 629
From: S. Florida
Default

You're referring to the 88mm wheel correct? Which exhaust housing though...is the .94 going to be too small?
Old 10-16-2003 | 07:36 AM
  #29  
93 R1's Avatar
Senior Member
 
Joined: Sep 2002
Posts: 3,867
From: Maryland
Default

Originally Posted by jspecracer7' date='Oct 15 2003, 06:14 PM
[quote name='93 R1' date='Oct 16 2003, 02:37 AM'] I agree with you. There isn't really a need for 12,000 with 20 psi, but it does sound badass.



So why do most people bridge the secondaries, instead of primaries when doing a half bridge? Just trying to understand the logic between the 2. I had an indepth conversation with Judge Ito about this, since he will be building my half bridge. He never mentioned bridging the primaries instead......





Basically I want what IGY has. A car that will scare the **** out of people, and just put a huge smile on my face everytime I drive it. IGY what kind of power was your car making roughly?
lol...your going to have a beast of a car if you want to replicate IGY's BP motor. I was destroying cars left and right when IGY was tuning it. At 1.3 kilos, even 20B's were being left in the dust [/quote]

Old 10-16-2003 | 04:07 PM
  #30  
Badog's Avatar
Senior Member
 
Joined: Jul 2001
Posts: 273
From: oHIo
Default

Originally Posted by rx7tt95' date='Oct 16 2003, 09:02 AM
You're referring to the 88mm wheel correct? Which exhaust housing though...is the .94 going to be too small?
Hottie side 1.19AR!


Quick Reply: Let's Examine The Gt40



All times are GMT -5. The time now is 09:19 PM.