Originally Posted by Kamaro

Thanks for the great info, this really summarize it so cleanly. I have one question, though, Will a larger displacement engine (a stroker) be effected less with overlap than stock displacement, like 416 stroker LS3 vs 376 stock?

For example, I had a cam with 12* overlap in a stock LS2 which was not so great in low RPM, if I ever use the same cam in 416, will I be seeing less surging/bucking at the same RPM?

Is there a borderline where I can have enough overlap to make a good scavenging effect but not enough to cause any low RPM drivability issue?

Originally Posted by CAMMOTION PERF

The larger displacement stroker needs more air and fuel to feed it. So, it will need more duration and lift to feed it with a given heads and intake. With this, generally comes more overlap. There is no certain or magic number or amount of overlap. I hate making generalizations, but on street sized cams, as the overlap goes up the cam gets more powerful in the upper RPM. The sweet spot for you will be where acceptable manners and desired power output meet. That could be negative 5 degrees, 0 degrees or posiitive 10 degrees at .050". I think if most street car enthusiasts chose thier camshaft based on driving experience alone, they would choose less aggressive cams than most do. But, we all get excited by a big dyno number and/or a tough sounding idle. A well designed mild camshaft will make just as much power or more up to around 5500 RPM than a comparably aggressive camshaft. But, it wont make that big peak horsepower that we can boast about. The struggle is real

Originally Posted by MuhThugga

The carbon does look a little heavy on the exhaust side on that piston, but with the reversion that is going on, the engine isn't effectively exhausting the cylinder in that 1500-1800 RPM range, which could explain the build-up.

Originally Posted by Justin93

Your not kidding about the struggle. Honestly I'd probably be alright with only making 467 rwhp in a 403 if the drivability was better. The bucking gets so bad at times I think I'm going need to visit a chiropractor lol. What's your suggestion on cams you offer for a L92 headed N/a stroker? Car sees 50/50 street and track. I'm thinking about selling this cam and getting in touch with you guys

Originally Posted by CAMMOTION PERF

I created a camshaft just for guys who wanted the extra torque of a stroker, but still wanted great street manners. It is the "Stealthy Stroker": http://store.cammotion.com/stealthy-...rectangle-port . This camshaft will drive great. It will have good power everywhere and never irritate you. However, it will not set the dyno on fire. It is 230/240 on 116+4 with .621" lift. It has 3 degrees of overlap at .050"

A reasonable compromise might be something like a custom 234/242 on 115+4. This camshaft will have 8 degrees of overlap. With this camshaft, you will still have a defined lope, but much milder than what you have now. It will still buck a bit, but at a much lower RPM. This camshaft is not a dyno killer either, but it will make a more than the Stealthy Stroker.

Originally Posted by Kamaro

I'm really interested in that cam (Stealthy Stroker), do you offer them for catdral port heads as well?, I have a set of PRC 237 heads that I would like to use on my 416 LS3 based engine.

Originally Posted by CAMMOTION PERF

I created a camshaft just for guys who wanted the extra torque of a stroker, but still wanted great street manners. It is the "Stealthy Stroker": http://store.cammotion.com/stealthy-...rectangle-port . This camshaft will drive great. It will have good power everywhere and never irritate you. However, it will not set the dyno on fire. It is 230/240 on 116+4 with .621" lift. It has 3 degrees of overlap at .050"

A reasonable compromise might be something like a custom 234/242 on 115+4. This camshaft will have 8 degrees of overlap. With this camshaft, you will still have a defined lope, but much milder than what you have now. It will still buck a bit, but at a much lower RPM. This camshaft is not a dyno killer either, but it will make a more than the Stealthy Stroker.

Originally Posted by Camaro99SS

The OP's static compression is only 10.9:1. Wouldn't that later intake closing point from the 116 and 115 LSA bleed down too much cylinder pressure to not lose a noticeable amount of mid range and low end?

Originally Posted by Justin93

Well, I finally got my 403 build done and tuned back in May. After driving it for a few months I'm fairly happy with it but I came far short of my goal of at least 500whp. I've attached the Dyno sheet below. Car made 467 434 on a know to be stingy mustang Dyno. The car just doesn't feel very torquey to me and seems to run out of steam faster than I'd like. I spoke with btr where I bought my cam and they are insisting 1 7/8 headers will really open this setup up, but I'm a little skeptical of this. I kind of feel maybe the cam is leaving some on the table. With all the voodoo floating around out there on cam selection for rectangle port heads I'm not sure now if I made the right choice. Looking for suggestions as to what I could do to improve this setup and gain some hp and torque. Looking to keep it n/a. My current setup is listed below. Car is tuned on speed density. Thanks for the help

2006 GTO 6speed manual Ls2 block -Full Manley 403 rotating assembly with -4cc flat tops with reliefs -Rings gapped for N/a - Johnson 2110 lifters @ .035 preload -stock rockers with trunion upgrade -Stock L92 heads with btr .660 springs -Stock LS3 .051 thick head gaskets -static compression 10.9:1 -Btr N/a stroker cam Cam specs are 239/254 .624"/.595" 114+3. -Fast 102 lsxr manifold with NW102 throttle body -Pacesetter 1 3/4 headers with catless mids to custom 3in exhaust -stock ls3 injectors currently at 92% duty cycle. New 70Lb injectors and dw265 fuel pump waiting to go in. Attachment 549301