Poll: which cam?

[gadget73]

OK, so when I pull my motor back apart, which cam should I use? My options are an Explorer cam or the HO cam. I can also advance the cam. Engine specs in the signature. Mostly what I want is more low end grunt than the normal HO gives, and some more power for towing. Screaming high RPMs aren't as big of a concern since my trans shifts at 4800 rpm, and I dont really plan on changing that. I also do want respectable fuel economy when driving. I'm sort of on the fence between the HO advanced 4 degrees and the Explorer cam at 0 degrees. I plan to keep the speed density and the 19 lb injectors, so crazy aftermarket cams aren't really on the radar. Thoughts?

[gadget73]

96-'98 5.0L Explorer cam specs:

.264" intake cam lift (.454)
.280" exhaust cam lift (.481)
256º intake duration
266º exhaust duration
intake valve opens 10º BTDC
intake valves closes 66º ABDC
exhaust valve opens 66º BBDC
exhaust valve closes 20º ATDC
30º overlap

'85-'88 5.0L HO cam specs:

.278" intake cam lift (.478)
.278" exhaust cam lift (.478)
266º intake duration
266º exhaust duration
intake valve opens 17º BTDC
intake valves closes 69º ABDC
exhaust valve opens 67º BBDC
exhaust valve closes 19º ATDC
36º overlap

Keep in mind the lift figures above are directly at the cam. To get what most people would recognize, multiply by 1.6 for stock rockers, or 1.72 for my rockers. The numbers my particular setup would see are in parentheses.


Explorer intake flow numbers (since I was asked) can be seen here, with a cyl per cyl flow figure.

http://www.edelbrock.com/automotive/stories/sf609/intake_overload.html

Mostly I would like to move the power band downward a bit. The HO cam has that 'extra cylinder' thing about 2500 rpm. I want solid power before and beyond that point, not the somewhat boring windup before it actually decides to make power that the HO camshaft does. As a side benifit I imagine this ought to improve 60 foot times but since I dont really race on a regular basis its of less concern to me. I just want a nice wide flat power band thats appropriately suited to a 4400 lb car. I've driven an HO powered Vic with an advanced cam, and it doesn't seem to have that pronounced jump. Thats a stock HO with a 3.55 gear in the back. Scott's car with the ported heads and the cam at 0 degrees still has that jump feel, but its also not super pronounced. The only Explorer powered vehicle I've been in had a wide ratio transmission, so its not a direct compare but it does not have that kick in the power band. It makes power off-idle and pulls all the way through till the transmission shifts.

[OVERKILL]

The Explorer is a 5,000lb beast, so I'm assuming it's cammed as such. The HO cam definitely "comes on" at about 2,500, I notice it quite badly with my car, as I did with my Mustang with 3.08's in it. It really IS quite dead below that point, there's lots of torque, just no HP.......... at all. So I know what you mean. The Explorer cam was in a buddy of mine's Mustang and there really is a noticeable difference. You couldn't feel it coming on at all, it didn't. It made what seemed like power from idle to around 4,500-5,000RPM and it was DONE, my car with the stock cam seemed to pull harder up top.

I think the Explorer cam might be a neat thing to try.

[gadget73]

Only thing I've ever been in with an Explorer cam had weak valve springs, and it would float at about 4500. Ran balls to the wall, floated, shifted, went. I should not have such issues with valve float, and my trans shifts at 4800 WOT.

[p71towny]

Im gonna say advance the explorer cam. With those rockers, and it being a dual pattern setup, you should have the torque and economy you want. Im going aftermarket myself, but I'm like you, streetability is my #1 priority, power #2. I've got other projects for raw power.

[OVERKILL]

Gadget: if you REALLY want something wicked, get a hold of Jay Allen of Camshaft Innovations and he can do you up a custom-grind.

[gadget73]

Budget and effort are a factor here. The actual cam swapping isn't a big deal, but I don't want to fool with changing the fuel metering system, I don't want to have to buy custom pushrods, and I'm really not up for a bunch of tuning. Mostly I want to bolt stuff together like a boring motor and have it work. If this was more of a street terror that I didn't drive all the time I might be inclined to fiddle a little more, but I'm looking more for daily driver, highway cruiser, and on rare occasion a run down the track for giggles. I want to stick something in there and have it work. Also, both of these are on hand for little / no cost. I already own the HO cam so thats a freebie. At some point I might end up with mass air but if I can get away with not doing that, I'd prefer to keep my SD if possible/practical.

I think I might do the Explorer cam at 0 degrees. I dont really want to advance it because I'm afraid it would make it run out of steam quicker.

I found some dyno tests on a 98 Exploder, these are done on a stock motor and then again with the same vehicle and a set of headers. Considering how horrible the stock exhaust is, I can completely believe this improvement. I'm going to guess that my headers and 2.5" exhaust should in theory yield figures closer to the second pic.

http://www.torquemonsterheaders.com/test_results.html

This is a baseline dyno from a 95 Mustang with an auto

http://www.airflowresearch.com/95mustang_dyno.php

[Archangel]

Why so small numbers? Cause it's rear-wheel data that they take?

[OVERKILL]

Why so small numbers? Cause it's rear-wheel data that they take?

rear-wheel through a big slushy auto

[OVERKILL]

If it were in the budget, Jay could create you something that would PERFECTLY match your goals and needs for the car, IE, the daily driver part and remaining speed density, but still making wicked torque and power, and ultimately yielding the best power output possible.