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Old 09-15-2008, 03:08 AM   #1
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Default Exintake swap?

I read about an exintake swap in airbrush1's thread but didn't want to jack his, the mod consists of putting an exhaust cam in place of the intake cam. I did a search both here and on m.net and couldn't find much info.

Anyone wanna chime in? What would be a benefit of doing this? What would be a downfall if any?
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Old 09-15-2008, 03:10 AM   #2
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Apparently it gives you a few horses for NA power, not so much for boosted cars. try searching for exhintake (with the "h") and you'll probably get a few more search hits.
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Old 09-15-2008, 11:37 AM   #3
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"Apparently" being the operative word. Half of the people that try it claim it works, the other half see no benefit, with the only difference being that the powerband has been moved up in the RPM range.

That's the impression that I get from the Protege forums, anyway.
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Old 09-15-2008, 11:41 AM   #4
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The information is out there, but it's scattered and not well organized. In short you have to drill a locating hole in the cam gear so that the new exhaust cam is indexed correctly. 197.5* clockwise of the old hole is the right spot I think (from memory, go look it up).

This mod will increase lift and duration.
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Old 09-15-2008, 11:54 AM   #5
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If done on turbo car, it probably should be done with adjustable wheels to allow for the increased duration with less overlap. Should be a marked improvement in power if tuned.
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Old 09-15-2008, 01:29 PM   #6
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we need a definitive thread.
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Old 09-15-2008, 01:45 PM   #7
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Quote:
Originally Posted by airbrush1 View Post
we need a definitive thread.
Indeed, and it needs to pay strict attention to the separation of solid lifter and hydraulic lifter motors. I'll contribute what I know later from my research. I have an extra 99' exhaust cam I'm gonna put in some time. When I do it I will definitely take lots of pics and do a writeup, as the info on this swap for a 99 is terrible.
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Old 09-15-2008, 01:49 PM   #8
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Quote:
Originally Posted by patsmx5 View Post
Indeed, and it needs to pay strict attention to the separation of solid lifter and hydraulic lifter motors. I'll contribute what I know later from my research. I have an extra 99' exhaust cam I'm gonna put in some time. When I do it I will definitely take lots of pics and do a writeup, as the info on this swap for a 99 is terrible.
Try to do some before and after dyno pulls too if you haave time/access to a cheap dyno.
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Old 09-15-2008, 01:53 PM   #9
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Quote:
Originally Posted by KPLAFIN View Post
Try to do some before and after dyno pulls too if you haave time/access to a cheap dyno.
That would be nice. But it probably won't happen. I'm waiting to put the cam in till I get rid of this miss I have. I need two more Millenia COPs and I will switch to COP in hopes of remedying my ignition miss. Car runs strong right now, but I know having a random miss is holding it back some. Besides I'll probably see higher than typical gains from a cam swap as I have a lot of head work done.
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Old 09-15-2008, 10:22 PM   #10
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Quote:
Originally Posted by patsmx5 View Post
Indeed, and it needs to pay strict attention to the separation of solid lifter and hydraulic lifter motors.
Are all NAs mechanical? Also, what is the interval of adjustment on them?


Also, who did your head work? Cost?
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Old 09-15-2008, 10:26 PM   #11
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NAs have hydraulic lifters.
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Old 09-15-2008, 10:29 PM   #12
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They went mechanical on later cars? Really?
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Old 09-15-2008, 10:34 PM   #13
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Quote:
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They went mechanical on later cars? Really?
Yarly.
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Old 09-15-2008, 11:00 PM   #14
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Quote:
Originally Posted by fahrvergnugen View Post
Are all NAs mechanical? Also, what is the interval of adjustment on them?


Also, who did your head work? Cost?
89-93's have 1.6L and hydraulic lifters. Can't do the exintake swap on these though as the CAS sensor is driven off the intake cam. Bolt an exhaust cam in its place and there will be no provision to drive said sensor.

94-97's have the CAS driven off the exhaust side. Just cut the drive off an exhaust cam and install it in place of the old intake cams. Hydraulic lifters on this motor too.

99+ has solid lifters, and more aggressive cams.

I did my own head work.

EDIT: headwork cost me probably 200 tops. Would cost anybody I did it for 1K+
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Old 09-16-2008, 12:20 AM   #15
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Quote:
Originally Posted by patsmx5 View Post
99+ has solid lifters, and more aggressive cams.

I guess they went 'backwards' to wring every little bit of power they could out of that motor... I've been around VWs too long...


Quote:
Originally Posted by patsmx5 View Post
EDIT: headwork cost me probably 200 tops. Would cost anybody I did it for 1K+

Not to come off as critical, but did you have access to a flow bench? Or have you had prior experience with P&Ps?
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Old 09-16-2008, 12:27 AM   #16
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Quote:
Originally Posted by fahrvergnugen View Post
I guess they went 'backwards' to wring every little bit of power they could out of that motor... I've been around VWs too long...





Not to come off as critical, but did you have access to a flow bench? Or have you had prior experience with P&Ps?
I don't understand what you mean by the first part.

No I didn't flow bench the head, nor did I "port and polish it". If you're curious as to what I did PM me.
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Old 09-16-2008, 12:51 AM   #17
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http://members.aol.com/solomiata/cams.html

Scroll down, looks like same lift longer duration.
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Old 09-16-2008, 01:00 AM   #18
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Quote:
Originally Posted by iWeasel410 View Post
http://members.aol.com/solomiata/cams.html

Scroll down, looks like same lift longer duration.
94-97 that is true. 99-00 the exhaust cam has more lift and duration.
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Old 09-20-2008, 07:11 PM   #19
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Last edited by iWeasel410; 09-20-2008 at 07:12 PM. Reason: forgot the www
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Old 09-29-2008, 09:18 AM   #20
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We need more definite answers! I'm looking forward to doing this mod.
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