Emissions-legal ported heads?

I passed with Thumpers better than I did with regular E7's. Porting won't hurt emmisions at all.

"Porting won't hurt emmisions at all."

I think the statement is a little over reaching. First, there are probably differences between Maryland and Georgia's testing procedures; a combo that passes in Georgia may or may not pass elsewhere. Second, it's not just whether heads are ported or not. It's the entire combo - overall condition/mileage on the engine, mods, state of tune, etc.

While the E cam has a CARB number, I believe there are probably cams out there even without smog-legal 'status' that will actually produce lower tailpipe emissions on a mildly modded car. I'd look for something with 1) Less overlap/higher LSA, 2) perhaps a little less duration than the E, and 3) something with a little exhaust bias to match up with your E7's a bit better. Even so, you're taking some risk. I'd want to have a long talk with the emissions techs to find out exactly what their criteria are.

Your mods don't seem that extreme - why did it barely pass before?

Bolt On John said:

Well I blamed the O2 sensors, which have since been replaced. Thanks for all the good info.

Any MD ppl have any advice??

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with what you have i don't see why you wont pass emmisions... e cam should pass emmisions... i've heard people that didn't have the smog pump or the EGR and still passed... wasn't MD but still... i heard you can put something in your gas tank that could help, something like rubbing alcohol ... and yeah miles on you engine, when was you oil changed last time... there are many factors... ohh yeah PCV valve....

saniutza said:

with what you have i don't see why you wont pass emmisions... e cam should pass emmisions... i've heard people that didn't have the smog pump or the EGR and still passed... wasn't MD but still... i heard you can put something in your gas tank that could help, something like rubbing alcohol ... and yeah miles on you engine, when was you oil changed last time... there are many factors... ohh yeah PCV valve....

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In the shop that I used to work at, my boss used to put gas line antifreeze (alot of it) in car to get them to pass. He would put it in on a low tank, do the test then fill it up with reg. gasoline to dilute it back. worked every time, though it is probably not good to run the engine on it for too long

John, combo's that work and pass emmisions;

Dad's '89 GT... basic 306, mildly ported edel performer 5.0 1.90 heads, E cam, 1.72 rollers, C+L meter, 65mm throttle body, GT40 intake, FMS shorties, catco 2 cat replacement pipe, dynomax mufflers on stock tailpipes, AOD with 3k convertor and 3.73's.

And mine... Pushing 390RWHP with the blower. Basic stock 306 rebuild with forged pistons and total seal rings, box stock AFR 185 heads except fully studded worked by a Crane 2030 cam (216, 220, .533", .544") and 1.6 FMS rockers, 12" K+N feeding a ported and polished Paxton SN-92 blower through 3" stainless plumbing and a ported C+L meter, ported and smothed 65mm throttle body, well ported and smoothed GT40 intake (ported to match the AFR's), ported BBK lontubes, homemade H pipe with catco cats ($15 swap meet specials), MAC flowpath catback with 3" tails.

Pretty funny watching the girl run it on the dyno, kept overshooting the graph on acceleration really far, like she wasn't used to something with power. Asked her if it was her first time and she smiled, then asked if it was for sale. Car passed pretty easy.

The turbo coupe I just built fair much worse, but I found out that when I converted it I didn't hook up the o2 heaters... He retitled it up in Cumberland and doesn't have to worry anymore.


Jamie