Would I want a longer duration on a stock cubed H/C motor?
 

I'm really considering the Comp 228/228 .588/.588, but what I'm wondering is, is the 228 duration gonna make my power band really peaky? I was thinking about running this cam on a 111 lsa and a 108 icl. I'm trying to keep from spinning the stock bottom end too high, but I still want to make good mid-range and top-end power. Radical doesn't bother me one bit, but then again, I don't wanna be swapping springs all the time either. I'll be running the Comp 987's, and I'll also be replacing the lifters with Comp "R" pieces.

What do you guys think? This cam will be going along with a set of TEA St.2 5.3's. Also, I don't wanna have to worry about P to V clearance. Any opinions?

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Why not? Go with a 232/.588"-110. This is the cam I've been dieing to get in my ride. The motor will eat it up- choppy idle, but the lift won't chew up springs and the LSA will kepp the powerband down to a reasonable level- below 6800 rpm. This would be even better on a set of heads.
I CANNOT wait to try this combo out. I feel very strongly that this will put out over 450rwhp on TEA stg III heads and will not kill my bottom end.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

I HIGHLY suggest a ported oil pump of some kind, and PLEASE make sure you check P/V clearence.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

The oil pump will be replaced, I just forgot to mention it. ;) Also I'll be replacing the timing chain with a Rollmaster piece, and upgrading to the LS6 intake.

As far as the choppy idle, I could care less about that. As a matter of fact, the choppier the better! :D

Anyways, I never really thought about a 232, but I have considered a 230/230 .592/.592 on a 110 lsa. :devil:

Re: Would I want a longer duration on a stock cubed H/C motor?
 

i have a 234 238 600 591 on a 110 that will be coming out of my car next week. inetersted?

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Good christ, that is a HUGE cam.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

where did it peak and what kind of numbers did it put down? What mods are done to the car?

Re: Would I want a longer duration on a stock cubed H/C motor?
 

436 rwhp @ 6300 408 ftlbs @ 4600. all bolt ons are on the car plus this was done through a 12 bolt with 4:30s. it was also on a conservative tune since i spray every now and then.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

sorry i forgot i also have tea stage ii heads,

Re: Would I want a longer duration on a stock cubed H/C motor?
 

That's just a lil bit too big, and besides, I'm not wanting to run a traditional split. If I ran any type of split cam at all, it would be a reverse split, because the LS6 intake is the choke point, not the exhaust. ;)

Re: Would I want a longer duration on a stock cubed H/C motor?
 

We sell alot fo the TSP228 cams, with decked heads you will definately need to cut your pistons with decked heads. I know this because Trevor had his 228 on a 111. As far as the 232 cam, we also offer a 232/228 setup that I think has potential to make some good hp. If you want to get really crazy we have a 231/237 cam with 598/595 lift on a 112 :) :)

We check piston to valve on every car with a cam bigger than a 224R, better safe than sorry when it comes to p/v clearance :)

Jason

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Thanks for the input Jason. ;) P/V clearance will definitely be the first thing checked before installing the cam. I just want to go as big as I can without having to flycut the pistons.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Another thing Jason, on that 231/237 cam, why is the duration a traditional split, yet the lift is a reverse split. I'm not quite sure I understand the advantage of that. :confused:

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Well, if you've been following the progress with cams on a stock shortblock (H/C cars) the traditional splits are making the most power for the most part. The benefits of a reverse split seem to be tapering off with the larger cams from what I've seen (just look at the GM designed ASA Grand Cup cam that can produce 470RWHP with CNC LS6 heads.) The big power H/C setups from Cartek, LG and Eastside I believe are all large traditional split cammed cars. To answer your question (Jason can correct me if I'm wrong) I believe since the exhaust side has such a large duration there is no need to open the valve as much as opposed to the shorter duration intake side....

Re: Would I want a longer duration on a stock cubed H/C motor?
 

But if the intake on our cars are the choking points, wouldn't you want the duration on the intake side to be longer than the exhaust? :confused:

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Well, that certainly has been one of the arguments for a reverse split grind, but if you consider that most of these big traditional split cams have a 230+ intake duration already (quite large) what would make it possible for the burnt mixture to escape adequately in half the time or less...

Keep this in mind also.... all the GM designed cams I've seen (who designed the engine no less) are traditional splits from the stock cams all through the racing spec'ed ones.

What the reverse split does basically is it gives some of the benefits of a large cam while keeping the driveability of a smaller one with the shorter exhaust duration.... it's more of a compromise than an all out power producing cam IMO.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

Isn't scavenging going to be a problem with the larger split cams.....there has to be a point where too much of a split will start losing power.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

See, I also agree with this point. So far, I haven't seen any bigger than a 6 degree split in either direction though.

Re: Would I want a longer duration on a stock cubed H/C motor?
 

<--- runs a moderate sized cam

232/232 .574/.574 112

Re: Would I want a longer duration on a stock cubed H/C motor?
 

from what i've been told by Mark over at comp when i ordered mine, the reason we dont see much bigger splits than what we do is because of the intake to exhaust flow ratio. we have great heads on our motors and we dont need a whole monster of a cam to take advantage of them. stock heads for example flow (roughly) in the 230's on the intake and 200's on the ex. that puts the intake at about 86% of the exhaust. you really dont need to split the cam any more than 86% I/E wise to keep more of a flow balance in the motor. now take a look at some of our ported heads that make it closer to 92% i/e flow ratio, and you start to see why more and more single patterns as well as reverse splits are being used to keep tq numbers up there. you dont need nearly as much exhaust flow as you do intake because of lesser volume of the spent gasses. make sense?

this is why our cam patterns are so signifigantly diffrent than the LT1, SBC and other conventional small blocks. this same ideology applies to other 15* and 18* cyllinder heads too. hope that makes sense. i think i got lost in there somewhere too. :D