99 Black Bird T/A

iTrader: (4)

Can a 230/224 reverse split cam w/114 LSA pass emissions? You know like the Thunder cam but with more LSA for smoother idle and more emission friendly.

Does the longer intake duration cause reversion?

With the idle raised w/TB mod, will misfire codes show? SES light?

All impressive gains with the reverse split cams has got me thinking dual pattern instead of single pattern. What guidelines apply for passing emissions with dual pattern cams?

Any chance this would pass 240 IM testing?

Thanks

Geoff

iTrader: (3)

In my opinion doing a 230/224 with a 114 LSA is going to move the powerband up quite a bit. It would probably put the power in a range that isn't usable for the average street car.

Part of what we were trying to do by increasing the intake duration was to increase cylinder filling ability at higher RPM's in spite of the tuning affects of the intake. The catch to this is that normally you will lose low end torque in order to increase your top-end efficiency. By tightening up the LSA you typically boost midrange with a slight loss on the top-end. For the intended RPM band of Jason's motor (below 7000 RPM) we got what we wanted as far as no torque loss and a nice boost in the top-end power, but I must stress that the 230/224 cam with a 114 LSA in his motor would probably want to turn 7200 RPM or more and have signifigantly less midrange torque.

At least from the testing we have done my opinion is this: The 230/224 is a more powerful cam in the RPM range that most people operate their cars than the 224/224 but it definitely has a choppier idle and is less likely to pass emissions testing.

Hope this helps.

SSBoy

It depends on how tough your emissions testing is in your state. some states are tougher than others. In cali, i think thats a lil too much duration. i dont *think* it would pass in california.

99RamAirTA

what abot a 112 lsa, I know its not much of a jump but would this idle any better. Also, would it raise the power band like the 114 or woud this still be within reason. How about emissions. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

99RamAirTA

what abot a 112 lsa, I know its not much of a jump but would this idle any better. Also, would it raise the power band like the 114 or woud this still be within reason. How about emissions. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

99 Black Bird T/A

iTrader: (4)

I think even a smaller Hammer Cam with 222/222 ish duration on a 112 LSA is borderline on passing the sniffer part of the emissions test.

I'd hoped since T1 & B1 cams perform pretty much the same with 112 LSA and 114 LSA, the reverse split cams might react in a similar manner.

I know Thunder was testing 111 LSA to pull the power band down in the RPMS, and it worked very well.

Anyone know how a small reverse split like 224/221 would work on a emission friendly 113-114 LSA?

Ragtop 99

iTrader: (7)

TTT for the 112 LSA Question. Been thinking about that myself. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

<small>[ May 10, 2002, 12:01 PM: Message edited by: Ragtop 99 ]</small>

CHRISPY

raise the idle speed up to 1200rpm with Ls1 edit <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
With good cats you would be amazed at how well you'd do <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Cheers,
Chris