Xfire intake mods
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Xfire intake mods
Hello,
I have a stock 1984 4 plus three. I purchased a xfire manifold to port, so I can keep from messing up my original intake.
Is porting the point where the runners contact the head enough. I mean are the runners big enough to permit enough air to make a significant increase in performance.
I took a quick look at the renegade and it looks like the runners are larger than the ones on the stock intake. So are the runners on the Renegade larger?
How do I measure the fuel pressure. I know how to measure from the pump. But is there a way to measure and change the pressure from the regulator.
Thank you,
Joe
I have a stock 1984 4 plus three. I purchased a xfire manifold to port, so I can keep from messing up my original intake.
Is porting the point where the runners contact the head enough. I mean are the runners big enough to permit enough air to make a significant increase in performance.
I took a quick look at the renegade and it looks like the runners are larger than the ones on the stock intake. So are the runners on the Renegade larger?
How do I measure the fuel pressure. I know how to measure from the pump. But is there a way to measure and change the pressure from the regulator.
Thank you,
Joe
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Renegade is the way to go if you can get one.
The stock CFI runners are so small, you can not hurt anything by porting too much. The more metal you can remove from those runners, the more power the intake will make. If you "vent" it, use a good quality epoxy to repair and it will hold.
FP is the same everywhere in the fuel system from the outlet of the pump, to the regulator (unless you have a major restriction like a kinked line or totally clogged filter). You should be able to "T" in to the feed line anywhere and get a legitimate reading.
Adjust by changing the pre-load on the spring in the fuel pressure regulator.
The stock CFI runners are so small, you can not hurt anything by porting too much. The more metal you can remove from those runners, the more power the intake will make. If you "vent" it, use a good quality epoxy to repair and it will hold.
FP is the same everywhere in the fuel system from the outlet of the pump, to the regulator (unless you have a major restriction like a kinked line or totally clogged filter). You should be able to "T" in to the feed line anywhere and get a legitimate reading.
Adjust by changing the pre-load on the spring in the fuel pressure regulator.
Melting Slicks
Joined: Dec 2009
Posts: 2,229
Likes: 284
If your really serious about porting the stock intake it might be a good idea to have someone tig weld some beads on the underside of the intake, the area just before the flange. This will allow you to port more & further in on the floor side.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
Last edited by ex-x-fire; Aug 23, 2013 at 07:28 PM.
Racer
Joined: May 2008
Posts: 391
Likes: 1
From: Greenwich Ohio
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
If your really serious about porting the stock intake it might be a good idea to have someone tig weld some beads on the underside of the intake, the area just before the flange. This will allow you to port more & further in on the floor side.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
If your really serious about porting the stock intake it might be a good idea to have someone tig weld some beads on the underside of the intake, the area just before the flange. This will allow you to port more & further in on the floor side.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
There's a picture of a cross sectioned cfi intake in my album, the area where I'd add material is below & right of the tape measure. If fact, you could have the whole coolant channel welded closed at both end, add more material to the floor & then port like crazy.
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Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Hello,
I have a stock 1984 4 plus three. I purchased a xfire manifold to port, so I can keep from messing up my original intake.
Is porting the point where the runners contact the head enough. I mean are the runners big enough to permit enough air to make a significant increase in performance.
I took a quick look at the renegade and it looks like the runners are larger than the ones on the stock intake. So are the runners on the Renegade larger?
How do I measure the fuel pressure. I know how to measure from the pump. But is there a way to measure and change the pressure from the regulator.
Thank you,
Joe
I have a stock 1984 4 plus three. I purchased a xfire manifold to port, so I can keep from messing up my original intake.
Is porting the point where the runners contact the head enough. I mean are the runners big enough to permit enough air to make a significant increase in performance.
I took a quick look at the renegade and it looks like the runners are larger than the ones on the stock intake. So are the runners on the Renegade larger?
How do I measure the fuel pressure. I know how to measure from the pump. But is there a way to measure and change the pressure from the regulator.
Thank you,
Joe
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
http://forums.corvetteforum.com/memb...ire-31877.html my pics !!!!!!!!!!!!!!!
Do you know how much horsepower the porting gave you
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Being I will have the intake off and they are right there. I was thinking of putting roller lifters. Any opinions out there? I will probably go to roller lifters in the near future.
Oh if I use rollerlifters do I use linked or use the pan that holds the lifters in place.
Oh if I use rollerlifters do I use linked or use the pan that holds the lifters in place.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Melting Slicks
Joined: Dec 2009
Posts: 2,229
Likes: 284
That picture is a xfire intake cut in half to show the small ports & coolant channel that runs under it. It doesn't show the egr channel.
I had my intake extrude honed in '97, I wasn't that impressed with it. It seems like that process makes everything smooth with out a lot of material removal. I would have been better off hand porting it & then sending it out to extrude hone.
I ended up going with a conventional type dual plane intake with a truck tbi unit on it.
I had my intake extrude honed in '97, I wasn't that impressed with it. It seems like that process makes everything smooth with out a lot of material removal. I would have been better off hand porting it & then sending it out to extrude hone.
I ended up going with a conventional type dual plane intake with a truck tbi unit on it.
Racer
Joined: Oct 2012
Posts: 294
Likes: 0
From: Spokane WA