Thunder racing

[ff_jeff]

I would have to strongly disagree with that first part although of course everyone is entitled to their own opinion(Not trying to start and argument, but rather a discussion).

As you increase the duration of the cam the power band is shifted not increased. The stock cam stops making power well before you shift. If it were that case then we'd all be running massive cams, and never thinking twice about it.

I will post a bit of a personal example.

I ran an 11.2 in the 1/8th with my comp cams 224/224 on 112 lsa. That was with a 2.7 60' time and NO WHEEL SPIN even on an open differential.

The loss of low end was ridiculous.

After I added my ss3600 torque converter I was able to run an 8.9 and even that time was way higher than it should be as I was running 2.2 60' times with horrible wheel hop.

I gained about 14 mph in trap speed(67 mph to 81 mph) in just the 1/8th mile from swapping to a higher stalling torque converter and putting in long tubes. Nothing else.

There is no doubt about it in my opinion.

Also, it's pretty hard for me to prove my point with dyno graphs since most places usually start recording on the dyno around 3000 rpm

So your saying that you had a better 1/8 mile with a stock cam? I can vouch for aggressive cams having no gains on the bottom end. My cam in my 4.8 didnt even hit power until 4k rpms. But dyno side by sides show that before 4k rpms, graph was identical. After that it got a 60+whp gain all the way to 6500. Another thing is I said ''usually'' in bold letters. Because people think that they are going to see 50whp below 3k rpms, with just a cam.
If you put a 3600 stall on anything, you will see better times. Doesnt mean that you gained any power, or lost any. It means the stall is keeping the engine in the wanted rpm range at WOT. The reason they dont start the dyno until after 3krpms is because any power down there is moot. Show me a dyno of a 4.8 or 5.3 n/a that makes 300whp below 3000rpms. And if you find one, copy his setup. That way when you put your foot in the gas you get nothing because your only at that rpm in 1st gear.
Oh and not all high duration cams are for hi rpms... a lot of them make power alll over the rpm range.

+1

-1 PH

[GasGuzzler]

-1 PH

What's PH?

Anyway I can agree with most of his quote because you two are discussing different points. Apples to oranges.

My cam in my 4.8 didnt even hit power until 4k rpms. But dyno side by sides show that before 4k rpms, graph was identical. After that it got a 60+whp gain all the way to 6500. Another thing is I said ''usually'' in bold letters. Because people think that they are going to see 50whp below 3k rpms, with just a cam.
If you put a 3600 stall on anything, you will see better times. Doesnt mean that you gained any power, or lost any. It means the stall is keeping the engine in the wanted rpm range at WOT. The reason they dont start the dyno until after 3krpms is because any power down there is moot.

Wow I never knew the 4.8 didn't make decent stock cam power until 4K. That's another good reason to go 6.0 The side by side comparison is kinda neat especially considering you were running that ASA cam...in a 4.8. It's pretty cool that it didn't lose anything below 4K but it won't be like that for all applications (you're not saying it would be). I'm not sure the same thing would happen to a 6.0. Since they're bigger, have bigger valves, and have a bigger stock cam, I'd bet you'd lose almost as much below 3K as you gained above 4K.

Yes, apples and oranges by me now too...

Ask anyone with a bus like mine if power below 3K is moot. Sure it is for you guys with loose converters and spray but not to everyone.

[randomhero]

So your saying that you had a better 1/8 mile with a stock cam? I can vouch for aggressive cams having no gains on the bottom end. My cam in my 4.8 didnt even hit power until 4k rpms. But dyno side by sides show that before 4k rpms, graph was identical. After that it got a 60+whp gain all the way to 6500. Another thing is I said ''usually'' in bold letters. Because people think that they are going to see 50whp below 3k rpms, with just a cam.
If you put a 3600 stall on anything, you will see better times. Doesnt mean that you gained any power, or lost any. It means the stall is keeping the engine in the wanted rpm range at WOT. The reason they dont start the dyno until after 3krpms is because any power down there is moot. Show me a dyno of a 4.8 or 5.3 n/a that makes 300whp below 3000rpms. And if you find one, copy his setup. That way when you put your foot in the gas you get nothing because your only at that rpm in 1st gear.
Oh and not all high duration cams are for hi rpms... a lot of them make power alll over the rpm range.


-1 PH

I agree there are exceptions to every rule, but I still disagree with your point(once again pure opinion not fact).

Like I said in my post, it's very hard to compare dyno graphs because most dyno operators start recording the pull around 3000 rpm. You'd really need to see what kind of power it made between 1500-3000 to prove or disprove my point.

And yes I most certainly lost low end after the cam swap. I know this isn't a good judge of power, but it is still a good example, but before the cam I was able to at least spin the tire(open differential) from a stand still. After the cam swap I wasn't even able to spin my tire at all. That's will all other variables the same.

As far as the 1/8th mile times, I could only assume my stock 1/8th mile times would be better. An 11.2 is equivalent to a 17.xx 1/4 mile time. I made that pass in the fall in 50-60* weather. No 5.3L extended cab or even crew cab should run a 17 second 1/4 mile time in good weather.

[ff_jeff]

I agree there are exceptions to every rule, but I still disagree with your point(once again pure opinion not fact).

Like I said in my post, it's very hard to compare dyno graphs because most dyno operators start recording the pull around 3000 rpm. You'd really need to see what kind of power it made between 1500-3000 to prove or disprove my point....
...As far as the 1/8th mile times, I could only assume my stock 1/8th mile times would be better. An 11.2 is equivalent to a 17.xx 1/4 mile time. I made that pass in the fall in 50-60* weather. No 5.3L extended cab or even crew cab should run a 17 second 1/4 mile time in good weather.

ok so prove me wrong. Keep an eye out for a dyno with numbers below 3k rpms, that show stock cam vs at least 2 other cams that are mid to higher duration. Keeping in mind that stock stalls can flash. And they brake stall from 1500-2200.
Oh and stock 4.8/5.3 cc and ec do run low 17's high 16's stock. especially with open diffs.
edit: another point I have is that my 60ft stayed the same from before and after my cam. But I had a locker. no stall. slicks didnt matter either. 2.38 was my best 60 and I was not spinning, just never had any power down there. But 1/4 mile went from 15.7 @87 with tune, locker, intake, and headers. 14.6 @ 97 With just a cam and pulley swap. 60ft was the same. You put a 3600 stall on either one of those scenerios and you can shave almost a second off. ecsb 4.8

[Show&Go]

When people state you lose low end maybe they are talking more about torque? I know with certain cams in trucks they are a slug off the line... Could the torque curve be more of the decideing factor which would be different on every cam? I know a friend that just did a cam swap lost a few 10ths on this 60ft while gaining it back on the top end and more...

[GasGuzzler]

There you go.

[randomhero]

When people state you lose low end maybe they are talking more about torque? I know with certain cams in trucks they are a slug off the line... Could the torque curve be more of the decideing factor which would be different on every cam? I know a friend that just did a cam swap lost a few 10ths on this 60ft while gaining it back on the top end and more...

Horsepower and Torque are directly related. They are both mathematical forms of measurement that equal each other at 5250. They saying "Building a torque monster" basically just implies that your vehicle begins to make power much sooner than a normal car would. You may have already known that, but just adding it for those who don't.

And I'm working on finding an answer to prove or disprove my theory. Like I said, it's extremely hard since most dyno operators start recording around 3000 rpm.

Just so we are clear this is going to have to be proven with a big cam(224/224 or larger). A 212/218 or similar isn't nearly big enough to prove either one of our points.

[ff_jeff]

Horsepower and Torque are directly related. They are both mathematical forms of measurement that equal each other at 5250. They saying "Building a torque monster" basically just implies that your vehicle begins to make power much sooner than a normal car would. You may have already known that, but just adding it for those who don't.

And I'm working on finding an answer to prove or disprove my theory. Like I said, it's extremely hard since most dyno operators start recording around 3000 rpm.

Just so we are clear this is going to have to be proven with a big cam(224/224 or larger). A 212/218 or similar isn't nearly big enough to prove either one of our points.

224 is not a large cam. IMO a 23x to 24x with over 600 lift is a larger cam. 224 is a mild cam, well in terms of ls motors. You and I have different points. My point is that usually people think that they have lost their low end, when really its the same, or maybe a few hp difference, they never really had any low end to loose. (when they buy mild cams). Your point is that my point is you just need to prove it. I didnt call you out, you are calling me out. So your going to have to do your homework. I have done mine
edit: a tq monster is a motor that makes a lot of torque. Because all of our motors start to loose torque above 5250. A 4.8/5.3 will never be a TQ monster. Not without FI.

[Jermoslin]

I was just asking about the power range of this cam. I Have my shift points set around 5800 and would I have to rev the motor longer or would keeping the motor under 6000 be worth it. If not I will get the TR220 on 112 but the price is good on the 224.

[randomhero]

224 is not a large cam. IMO a 23x to 24x with over 600 lift is a larger cam. 224 is a mild cam, well in terms of ls motors. You and I have different points. My point is that usually people think that they have lost their low end, when really its the same, or maybe a few hp difference, they never really had any low end to loose. (when they buy mild cams). Your point is that my point is you just need to prove it. I didnt call you out, you are calling me out. So your going to have to do your homework. I have done mine
edit: a tq monster is a motor that makes a lot of torque. Because all of our motors start to loose torque above 5250. A 4.8/5.3 will never be a TQ monster. Not without FI.

A 224/224 in a 5.3L is a fairly large cam. There is no doubt about that. If you have a larger cubed motor then duration would increase based on engine size. A 230/230 isn't going to react in a 4.8L the same as a 408(I'm sure you knew that).
I've already said it several times that it's almost impossible to prove my point with a dyno graph (although I have been looking for them). I am also working on some input from people over on pt.net since there's quite a bit more traffic over there.

I did give you my input from personal experience. Gaining 14mph in trap speed just by swapping a converter is a pretty impressive feat. That's the best I can do until I find some hard evidence. I will tell you right now you won't drop almost 1.5 seconds by just adding a torque converter on a stock vehicle.

I wasn't calling you out, and I wanted to stress that I wanted it to be a discussion more so than an argument. If I'm offending you then it wasn't my intent.

Here's a good test for you as well. If you have a truck with a big cam go drive it on the highway at 55 mph with the torque converter locked up and on an incline. I can almost guarantee you you will have to downshift in order to maintain speed. Then do that same test with a stock truck and the results will be much different.

usually when people say they lost ''low end'' really what happened was that they gained more up top than down low. The low end is actually the same.

That's a pretty broad statement and it's quite a bit different than what you just said in your previous post. This is what I was disagreeing with.