As the title states I'm trying to find out if my engine has been ported and if there is a way to tell without dismantling the engine and inspecting the ports. I know it was rebuilt but do not know if it was just a "stock" rebuild. I took a trip recently to my home town and met up with a friend that has a 91 N/A GXL, mine is a 90 N/A GXL. He has a similar setup to mine, headers, cat delete, to a single side cat back, his is HSK hi-power and mine is Corksport power series. They both have about the same amount of miles since rebuild but mine seems to have more power, and different idle characteristics. I know it's not much to go off of but I figured with the vast knowledge of the forum someone would be able to answer my question or point me in the right direction.

 

With the lim off if it was bridged you can feel the extra bridgeport down the intake port on the irons. As for a street port not sure

 

How much vacuum does it pull at idle?

 

Thank you! I'm planning on installing the Pineapple 5 & 6 port sleeves so I'll check then. I'm not sure what kind of port it could have. It has a very pronounced exhaust cycle. Even with the stock exhaust it was very pronounced and even more so now that it's an unrestricted system.

 

I'm not sure. I've been looking at getting a vacuum gauge. What would the idle vacuum pull be if it were ported?

 

if it was a stock port on an engine with good compression, vacuum would be around 17mmhg but ported could be anywhere from 10mmhg to 15mmhg

 

Vacuum depends on what RPM its idling at too.

 

The lower the mmhg would indicate a more aggressive port given the engine has good compression?

 

It idles approximately at 800rpm

 

^ irrelevant until you get a boost/vac gauge

 

I'm going to pick up a vacuum pressure tester on Friday and I'll report my findings then. But in the mean time I took a quick video of my car idling. I know it's black but it was dark when I took it.
<iframe width="420" height="315" src="http://www.youtube.com/embed/4i0ohR7aswg?rel=0" frameborder="0" allowfullscreen></iframe>

 

If it was bridged ported he would know it right away brap brap baby!

 

Doesn't "sound" ported, but then again street porting isn't supposed to affect idle quality.

 

I know it's not bridge ported, but I'm definitely getting a vacuum gauge to see what it's pulling.

 

just get an after market boost gauge to replace the iffy-at-best electronic stocker

 

the best cheap way is to take off the intake manifolds and stick a small mirror that you can bend into the intake port, shine some light in there and look at the port. You can also try and feel the shape of the port with your fingers. If the ports are "sharp", its still a stock port. If you see that the bowl has been smoothed out, its likely that its also ported.

 

sorry I don't have an answer to your question but I am running headers and high flow cat and I was wondering how loud the setup is with the hks exhaust?

 

Thanks! Like I posted before I'm getting the Pineapple 6th port sleeves and I'll make sure to check that out while I have the intake off.

 

With not cat it's only loud at WOT, I would say since you have a cat it will sound nice and not make your ears bleed at full throttle.

 

I just got it cleared up by the guy that rebuilt the engine. It is not ported.

 

Tell your friend to check his vac lines for leaks and see if there is one, if there isn't compare your air to fuel