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Question about porting exhaust

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Old 07-03-10 | 09:14 PM
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FC3Sdrift's Avatar
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From: St. Thomas
Question about porting exhaust

I got the Pineapple racing EP2A for my exhaust port, i just have 2 questions about porting it,

#1 the bottom goes below where the exhaust sleeve sits, do i just angle it so it matches up to the exhaust sleeve.

#2 do i shape it to the size of the template and then put the tapered edge, or should it have the taper included in the size of the template??

heres a picture of the template over the exhaust port, its not perfectly centered but the height is right

Old 07-03-10 | 09:38 PM
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From: cold
should it have the taper included in the size of the template??
That's what I did on my EP3A.
Old 07-04-10 | 12:00 PM
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From: St. Thomas
what about the bottom just taper it down from the edge of the exhaust insert?
Old 07-04-10 | 12:44 PM
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From: Central Florida
is this a ruleset for a racing engine? if not then port to size then taper. i align the corners up with the top port, rule of thumb is you don't want to port up into the intake side of the opening as much as possible which results in less torque. the opening can be ported flush with the exhaust port sleeve, just don't port it over that or the port sleeve with distort under high horsepower applications(i've seen the port sleeves twist up like pretzels before).
Old 07-04-10 | 01:16 PM
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Originally Posted by Karack
(i've seen the port sleeves twist up like pretzels before).
Pics! Just because I want to see the destruction, not because I doubt you. What about an earlier opening causes the sleeve to succumb to the heat?
Old 07-04-10 | 01:38 PM
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From: Central Florida
Originally Posted by SpeedOfLife
Pics! Just because I want to see the destruction, not because I doubt you. What about an earlier opening causes the sleeve to succumb to the heat?
i'll see if he still has the sleeve, he wanted to keep it for some reason. i never said it warped due to an earlier port opening, it will happen if you port the opening too large that the exhaust forces its way behind the sleeve which heats it up and allows pressure to get behind it under boost. granted it only happened due to warn port sleeve pins in combination with running 17psi psuhing 450whp.

an example of this would be T2 sleeves in the RE cosmo rotor housings which have an excessively early port opening which the T2 sleeves won't cover and the exhaust winds up pushing under the sleeve opening. isn't an issue with the a-spec rotor housings, just a precaution when porting too large or too early.
Old 07-04-10 | 01:51 PM
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From: St. Thomas
I have the Pineapple racing medium street port templates (which is small SP for 13b-rew)
and the EP2A exhaust template

i didnt want to stray to far from stock ports, i just want to make the same power on a little less boost

heres what the intake templates look like, how would that effect my power, my numbers in my sig are with stock timing lines but with the runners all cleaned up and ported


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