[ZLRob]

Originally Posted by WiggyB

Thanks for the input I really appreciate it. I talked to a rep from BTR earlier this morning and they pretty much stated the same thing you mentioned. Its just better hearing it from someone that has some real world experience with it instead of listening to a sales person. I pretty much had my mind set on this cam but you just solidified my decision. Thanks a bunch for the input.

I just decided to run with it and use it because I wanted to stay within a failsafe window to where I could always fall back on OEM calibration if I ever needed to, and this cam was only slightly more hot than the LT4 cam so I figured with the extra fuel lobe and the increase lift and duration it may actually net me a little bit more power.

I was always going to be happy being within the 700's HP range for power, but as of recent tuning escapades I found a higher ceiling for power on this thing actually exists in the 800's for HP without needing to spin the blower to the moon.

Glad I could be of help! BTR certainly seems to know their stuff evidently!

[18.2SS.1LE]

Originally Posted by ZLRob

I just decided to run with it and use it because I wanted to stay within a failsafe window to where I could always fall back on OEM calibration if I ever needed to, and this cam was only slightly more hot than the LT4 cam so I figured with the extra fuel lobe and the increase lift and duration it may actually net me a little bit more power.

I was always going to be happy being within the 700's HP range for power, but as of recent tuning escapades I found a higher ceiling for power on this thing actually exists in the 800's for HP without needing to spin the blower to the moon.

Glad I could be of help! BTR certainly seems to know their stuff evidently!

This cam isn't more "hot" than the stock LT4 cam, you get 12* more intake duration but 17* less exhaust duration.

[KingLT1]

Originally Posted by 18.2SS.1LE

This cam isn't more "hot" than the stock LT4 cam, you get 12* more intake duration but 17* less exhaust duration.

Overall, it has more 3 degrees more overlap (LT4 -34 vs Big Fuel -31), so technically it is a slightly larger cam.

[ZLRob]

Originally Posted by 18.2SS.1LE

This cam isn't more "hot" than the stock LT4 cam, you get 12* more intake duration but 17* less exhaust duration.

Originally Posted by KingLT1

Overall, it has more 3 degrees more overlap (LT4 -34 vs Big Fuel -31), so technically it is a slightly larger cam.

^^ this

Can't argue with the results either @18.2SS.1LE

It makes excellent power with quantifiable results over the OE LT4 cam too.

[18.2SS.1LE]

I suppose it could be "hotter" by also allowing less heat out of the exhaust ports with less duration and lift.

[18.2SS.1LE]

Originally Posted by ZLRob

^^ this

Can't argue with the results either @18.2SS.1LE

It makes excellent power with quantifiable results over the OE LT4 cam too.

I haven't seen the results vs the stock cam with a 32% fuel lobe. Would be an interesting back to back!

[ZLRob]

Originally Posted by 18.2SS.1LE

I haven't seen the results vs the stock cam with a 32% fuel lobe. Would be an interesting back to back!

I agree. It would. If they sold the LT4 with a 32% I would have went that way for the sake of keeping everything else basically 1/1 over the OEM DOD cam but this was and still is the only available option at the time, so I jumped on it with no thoughts on looking back (because there's always a bigger and better option available) looking at it from purely an emissions inspections standpoint. That was why I did mine the way I did.

[ZLRob]

One more thought, VVE is the ultimate indication of how much more air is being moved and while the table looks similar- esque speaking from a purely visual graphical standpoint to the OE LT4, it definitely shows more airflow throughout the entire range by a decent amount. The ported blower obviously helps in that respect but I have no prior basis for comparison, so I can't say exactly how much the difference would be if you weren't running a ported blower.

[18.2SS.1LE]

Originally Posted by ZLRob

I agree. It would. If they sold the LT4 with a 32% I would have went that way for the sake of keeping everything else basically 1/1 over the OEM DOD cam but this was and still is the only available option at the time, so I jumped on it with no thoughts on looking back (because there's always a bigger and better option available) looking at it from purely an emissions inspections standpoint. That was why I did mine the way I did.

I would imagine the intake side helps a good bit, despite losing from less exhaust duration/lift. Being that they will build you whatever spec cam you want, would you have blended the LT1 cam's intake specs with the LT4 exhaust specs for the most efficient OE spec camshaft?

[ZLRob]

Originally Posted by 18.2SS.1LE

I would imagine the intake side helps a good bit, despite losing from less exhaust duration/lift. Being that they will build you whatever spec cam you want, would you have blended the LT1 cam's intake specs with the LT4 exhaust specs for the most efficient OE spec camshaft?

Remember the old saying, "torque wins races, HP sells cars?"

Just to give you an idea of what that looks like, the majority of the aftermarket cams being sold out there get you big HP numbers at the expense of considerably lower TQ numbers. I see it in all of these guys builds all the time, 760 RWHP/ 684 TQ (example). The lack of pulling power over the band. The LT1 cam gave me a great increase in HP capability yes, but what really got me was the high TQ numbers. Though it didn't surprise me either based on the lack of lift the exhaust has compared to the LT4. It almost reminded me of a reverse split style cam. I used to run one in my LS2 and despite the negative commentary I got from people saying it wouldn't work for an NA application, it actually did, and quite well at that. I think at the time I was making around 450 RWHP with it compared to the OEM 330 with supporting mods and torque output on it was immensely higher than anything stock ever was which is what I liked.. It's almost like a cam created exhaust scavenging effect.

With saying that, I can't actually say whether or not it would be ideal to blend the LT1/4 cam specs together and that would make for a great performing one without actually testing it out. I think at the time BTR or GPI did recommend me a cam with a 220/223 .612/.615 custom spec or something like that, but I decided against it because of compatibility with the OE calibration and what it would do to drivability if I ever had to revert back. Based on specs alone you would think more is always better, but that is not the case with these engines when you PD them. It's been proven out many times by other folks running these big massive spec'ed shafts and not getting results out of them compared to their counterparts running smaller profiles and getting awesome performers out of them.

So yeah, my answer, is ultimately inconclusive, because if I was to do it again and try a custom spec that blends the two together I would probably wind up with something I don't like because I use my Z as a streeter, but there is always a chance that it may perform great. I think especially GM has been doing this for so long at this point that the grinds that they spec out are pretty on the money and efficient for their intended targets.

[18.2SS.1LE]

Originally Posted by ZLRob

Remember the old saying, "torque wins races, HP sells cars?"

Just to give you an idea of what that looks like, the majority of the aftermarket cams being sold out there get you big HP numbers at the expense of considerably lower TQ numbers. I see it in all of these guys builds all the time, 760 RWHP/ 684 TQ (example). The lack of pulling power over the band. The LT1 cam gave me a great increase in HP capability yes, but what really got me was the high TQ numbers. Though it didn't surprise me either based on the lack of lift the exhaust has compared to the LT4. It almost reminded me of a reverse split style cam. I used to run one in my LS2 and despite the negative commentary I got from people saying it wouldn't work for an NA application, it actually did, and quite well at that. I think at the time I was making around 450 RWHP with it compared to the OEM 330 with supporting mods and torque output on it was immensely higher than anything stock ever was which is what I liked.. It's almost like a cam created exhaust scavenging effect.

With saying that, I can't actually say whether or not it would be ideal to blend the LT1/4 cam specs together and that would make for a great performing one without actually testing it out. I think at the time BTR or GPI did recommend me a cam with a 220/223 .612/.615 custom spec or something like that, but I decided against it because of compatibility with the OE calibration and what it would do to drivability if I ever had to revert back. Based on specs alone you would think more is always better, but that is not the case with these engines when you PD them. It's been proven out many times by other folks running these big massive spec'ed shafts and not getting results out of them compared to their counterparts running smaller profiles and getting awesome performers out of them.

So yeah, my answer, is ultimately inconclusive, because if I was to do it again and try a custom spec that blends the two together I would probably wind up with something I don't like because I use my Z as a streeter, but there is always a chance that it may perform great. I think especially GM has been doing this for so long at this point that the grinds that they spec out are pretty on the money and efficient for their intended targets.

What kind of gains are you attributing to the LT1's increased intake duration and lift? We're not talking about large cams here, as ZL14EVA posted his LS9 OE spec cam picked up 4 mph in the 1/4. I don't think you'd see a drivability difference with the stock duration the car came with from the factory. The LS2 being naturally aspirated is a different animal. These boost applications need help getting the extra exhaust out of the cylinder as there's a hell of a lot more to move than an NA car.

Here's a dyno of a FBO X Port ZL1 with the stock cam but meth as it doesn't have the lobe for the fuel system. I don't think the stock LT4 cam is the limiting factor but fueling sure is.

My argument here is if OP is going to put a cam in for more fuel (and power) but wants stock drivability and reliability, there are limitless better options than a stock LT1 cam spec. The whole goal is more horsepower, why not make it more efficiently in the process?

[ZLRob]

Originally Posted by 18.2SS.1LE

What kind of gains are you attributing to the LT1's increased intake duration and lift? We're not talking about large cams here, as ZL14EVA posted his LS9 OE spec cam picked up 4 mph in the 1/4. I don't think you'd see a drivability difference with the stock duration the car came with from the factory. The LS2 being naturally aspirated is a different animal. These boost applications need help getting the extra exhaust out of the cylinder as there's a hell of a lot more to move than an NA car.

Here's a dyno of a FBO X Port ZL1 with the stock cam but meth as it doesn't have the lobe for the fuel system. I don't think the stock LT4 cam is the limiting factor but fueling sure is.

My argument here is if OP is going to put a cam in for more fuel (and power) but wants stock drivability and reliability, there are limitless better options than a stock LT1 cam spec. The whole goal is more horsepower, why not make it more efficiently in the process?

I understand where you're going as far as argument sake is concerned, and I agree, there are cams out there that make more power than LT1/4 specs. That I'll never negate. I've had this argument endlessly at this point with so many others. Not everyone wants to go all out on their internals builds though and not everyone wants to go through the hassle of measure this for pushrods, remove old valve springs, install new ones, run these lifters, degree this cam, and then you're going to need to replace this stuff sooner rather than later even if it's set up correctly because it is harder on the valve train, valve springs lifters etc. not to mention power levels past the mid 800's start requiring driveshaft changes, and even transmission internal upgrades (which just based on our interactions I'm pretty sure he's not looking to get into). He's looking for a solution that is easier to deal with that runs mostly stock stuff and if his upper limit is 850 RWHP with a Procharged set up, I'd say that's pretty darn solid.

If LT4 cam makes 850 full effort using meth without E85 I wonder what it would make full effort with E85 and no meth if it was produced with a 32% lobe.

LT1 with lobe will definitely make 850 full effort with E85. I gotta wonder what it would make with meth on gasoline. That is an experiment someone else would have to take on though because it's not one I'm willing to do myself.

[18.2SS.1LE]

Originally Posted by ZLRob

I understand where you're going as far as argument sake is concerned, and I agree, there are cams out there that make more power than LT1/4 specs. That I'll never negate. I've had this argument endlessly at this point with so many others. Not everyone wants to go all out on their internals builds though and not everyone wants to go through the hassle of measure this for pushrods, remove old valve springs, install new ones, run these lifters, degree this cam, and then you're going to need to replace this stuff sooner rather than later even if it's set up correctly because it is harder on the valve train, valve springs lifters etc. not to mention power levels past the mid 800's start requiring driveshaft changes, and even transmission internal upgrades (which just based on our interactions I'm pretty sure he's not looking to get into). He's looking for a solution that is easier to deal with that runs mostly stock stuff and if his upper limit is 850 RWHP with a Procharged set up, I'd say that's pretty darn solid.

If LT4 cam makes 850 full effort using meth without E85 I wonder what it would make full effort with E85 and no meth if it was produced with a 32% lobe.

LT1 with lobe will definitely make 850 full effort with E85. I gotta wonder what it would make with meth on gasoline. That is an experiment someone else would have to take on though because it's not one I'm willing to do myself.

That's not my argument at all, I'm not talking about using cams that even need a valve spring upgrade. I'm talking about having a cam custom ground for use with stock valve train for max reliability as that's what he's looking for.

[ZLRob]

Originally Posted by 18.2SS.1LE

That's not my argument at all, I'm not talking about using cams that even need a valve spring upgrade. I'm talking about having a cam custom ground for use with stock valve train for max reliability as that's what he's looking for.

Ohhh.. I got you now.. yeah I'm sure he could get a custom mild cam ground no problem. Something that mixes both LT1/4 specs together like the one we're talking about. He may just not want to go through the hassle of having to wait for it to get built for him though. I couldn't say though because I'm not in his situation. As far as the stock cam big fuel, this one is obviously an off the shelf and highly accessible if that's what is part of his criteria.