I have found another cam that is almost like the trex. http://www.ls1speed.com/catagory.cfm...in%20/%20Heads It is a custom grind from comp # S17 238/244 .605/.612 @110 as far as i understand, the higher the dur, the higher in the rpm band you will make power.?? And the more lobe overlap, the wider the power band..?? What do you guys think

 

very interested in this I've thought about that exact cam from them. It would be bad *** if the Speed inc. guys came in!

 

interesting I am cam buying soon so hope to here maybe some reviews, etc..

I knew speed inc had cams but it slipped my mind, I need to research a few of theirs as well.

 

Yah im curious to know what kind of power it makes and how well it does with a nice set of heads.

 

that's alot of cam, hope you got a killer engine combo and want to turn it hard.

 

I have that cam. I only have 3 dyno pulls and 10 passes with it and the tfs heads. still have to play with the tune a little bit. The times in my sig are off a footbrake and the stall/gear are a little small for this combo. My times will only get better, but I feel it was a pretty good start.

 

Your link doesn't work, try this one: Speed Inc. SI7 Cam

JPH is right, that is a whole lot of cam. It has 21* of overlap, so you can almost guarranty you'll need to lose your MAF and go with a speed density tune for any sort of drivability. Also, unless you install it on a 106* Intake Center Line, the peak power will be well after what an LS6 or FAST manifold will 'tune' to by design. Also, plan on 4.10 gears or a 4500 or so stall to work with that cam.

Generally speaking, yes - longer durations allow more time to fill the cylinders at higher rpms. Shorter durations can't do so, and fall off. All of that is somewhat dependant on the valve events. As for overlap, it really helps to scavenge the cylinder at high rpms, by allowing inertia of the exhaust gas, as well as any tuning effect of a well designed exhaust system to also help pull theintake charge in. As for the powerband, wider LSA's tend to have a wider powerband with softer peaks, while narrow LSA's tend to focus the power for a slightly better peak but over a shorter span.

In a nut shell, I hope you have 'racecar' in mind if that's what cam you want. Lots of people will tell you that "it's all in the tune" or that "any cam can be daily driven with a good tune", but the truth is that the cam is going to work against your tuner. At this level, its difficult to get decent street manners.

Above all, if its what you are willing to deal with (and fund as far as supporting mods go) then, you'll be happy. Otherwise, I'd look at smaller cams.

Sorry for the long rant, and good luck!

Hammer

 

Thanks for the help, I do want a big cam and am willing to deal with it but maybe it is a little bit to much. What would be a good size you recomend. I have all the bolt ons besides the fast intake and tb. I have p&p heads with prc dual springs.

 

I thought someone else might chime is with a recommendation, but since not...

I like the G5X3 for a big streetable cam. While it has a generous amount of duration, it also has enough advance ground in to give better than average low & mid range for a cam of its size. The large split in exhaust duration makes it possible, without the ugly VE's that can result with smaller splits.

On the 114LSA it has 10 degrees of overlap, but tends to still peak rather high. Getting it on a 112LSA bumps the overlap to 14 degrees and brings the power peak down some (still about 6500).

Perhaps others will comment.

Hammer

 

I get tired of giving recomendations, know one listens anyways. People just think bigger is better.

 

Very true - there is a camshaft pissing match always raging here. The lucky winner gets poor fuel economy, dismal street manners, and a whole lot of expensive supporting mods.

Sure sounds cool though, and runs great (from 4000rpms on up)


I'm sure all the TRex and other 240+ guys will be here soon to tell me how wrong I am...

:flamesuit on:

 

I love how people on here choose their cam by posting a Poll. That just cracks me up.

 

I totally agree with you, ive had a comp cams 238/242 and it was just horrible in all ways..idling at 1800, no power until 4 k and you had to spin the motor past 6500 at least.and this was with a tune..horrible street manners.
Now my car has a small 222/224 and underdrive pulley kit and it drives like stock and acts just like stock..why would you put a huge cam in a daily driver? Are the few peak hp # worth it?