1991 Grand Marquis Camshaft Recommendation

[jonmark1985]

Hi, I'm Jon, I'm glad to join the forum. I've been lurking around the forum for a couple days looking up tech and decided to finally join. I've been a ford fanatic all my life and have owned several trucks and a couple mustangs. I recently bought a 1991 Grand Marquis off a friend at work and want to race it at the local 1/8th mile dragstrip.

I am trying to decide between using the 5.0 HO camshaft or the 94-96 F150 5.0 camshaft. Elgin wants $220 for the F150 camshaft and $260 for the HO camshaft. Both engines made the same amount of horsepower and torque. I imagine the F150 camshaft would be better suited to a heavy car and low engine speed. However does the HO camshaft still have enough to pull such a heavy car and have the top end horsepower I want?

I am planning on installing mildly ported (gasket matched, thermactor bumps removed, valves unshrouded, and casting flash cleaned up) E7TE heads, a ported (as per tmoss instructions) HO upper and lower intake manifold, 19 or even 21 lb./hr injectors, a set of roller rockers, a HO EEC, and dual exhaust. I hope to run a small shot nitrous by the end of the summer. I also hope to install 4.11 rear end gears, a trac-lok differential and 295/50/R15s on the back of the car.

PS. Check out the poll at the top.

The specifications on the camshafts are...

F150 Camshaft
Valve Lift .421"/.447" I/E
Duration @ .050" 186°/197° I/E
Overlap 47°
Lobe Seperation Angle 115.5

HO Camshaft
Valve Lift .444"/.444" I/E
Duration @ .050" 210°/211°
Overlap 55°
Lobe Seperation Angle 115.5°

[johnunit]

HO.

The F150 camshaft is actually wimpier than stock. The HO is still milder than 99% of the aftermarket performance cams.

Also, try to find a used HO camshaft instead of buying new. They're fairly durable and common as muck. If you're willing to spend 260 dollars on a camshaft you'd be better off getting an aftermarket one from Comp, Lunati, etc. for the same price or even a custom one from a custom like Bullet for only slightly more.


As an aside, a looser torque converter would probably REALLY benefit that combo. Nothing crazy, even just a cheapo 2500ish rpm lockup converter from Summit would be a big improvement. Will this be a street driven car or a weekend toy or what?

If you haven't seen it already, this is a fascinating and incredibly detailed E7 porting writeup. He goes against the grain a bit, like claiming that there's no gain to removing the thermactor ports without other work, but the level of detail and data is worth checking out.

http://www.diyporting.com/E7OV.html

Oh and welcome to the forums. Sounds like an interesting project. Stick around, maybe post some pics.

[zoomie]

I have a couple of suggestions....... dump the e7s....get at least gt40 varient heads, explorer intake, for cams there is a few choices, but the one that remains the most tourqiest is the comp cam XE258 part no 35-510-8 combine with alexs parts drop in springs and a set of miller roller rockers and soem shorty headers of choice, 4.10s would rock and roll . for the comp cam its more or less a HO on steroids has almost the same grind as the Ho but with higher lift.

[mrltd]

I second the explorer parts. The GT40 stuff doesn't cost much more and you'll make a bunch more power. I'd stick with the HO cam though. And used cam, the roller cams don't wear like standard cams. And you can get them dirt cheap.

[zoomie]

I second the explorer parts. The GT40 stuff doesn't cost much more and you'll make a bunch more power. I'd stick with the HO cam though. And used cam, the roller cams don't wear like standard cams. And you can get them dirt cheap.

agree if your using stock stuff, the HO is a better peice.

[jonmark1985]

I have a complete 88' F150 302. I was planning on "rebuilding" that engine and converting it to roller camshaft. I also have a 1993 Thunderbird with 5.0 HO, but that engine had poor oil pressure and not much power. I was planning on taking 2 and making one, but the more I think about it, the further I want to stay away from using parts from the Thunderbird engine.

I've been thinking about using Crane's H-192/2667-2S-10 camshaft. I have given thought about buying a used camshaft, but I hope to race the car for several seasons and I'm okay with spending the cash on new parts if its something that is going to be a problem to find. They aren't many HO camshafts on Ebay at any given time.

I am familiar with the E7TE head and have ported a set already. I sold that engine and never found out how much power it made, or how my port work played with the power band. I don't want to spend the money on a set of GT40 heads or the time looking for them, and I don't want to deal with the plug angle issues that P heads have. So that's why I want to stick to E7TE heads.

I guess I should have asked if anyone who has run the HO camshaft felt like low end torque was adequate for such a heavy car or did they need a high stalled torque converter to compensate for low end torque.

[sxcpotatoes]

I have a '91 GMQ that has a '92 HO Engine & 4.30 gears (with purple rims). The torque is still kinda lousy, comparatively, down low. This thing will get up and GO much, much better than stock, but only after it's started rolling. It'll spin the tires then starts going, then when you get to 2nd-3rd is where the powerband really kicks in and you take off like a M-Fing rocket!

WHOLE 95-97 Explorer engines are $4-600 around here, some with as little as 98k or so. Maybe sell both engines, or scrap the Tbird motor and sell the F150 engine.

Then again, it's probably good not to have eleventy-billion ft/lbs of torque off the line as you want to get going, not have to worry about spinning the tires for the length of a football field before it hooks up.

Nothing better than wheelspin in an automatic when it shifts to second

[sxcpotatoes]

Oh, and I'd say the torque converter is a must, I didn't have the cash to do it when I was putting this car back together. Would probably improve things noticibly.

[johnunit]

If you have the money, custom cam and non-stock torque converter. The torque converter will make a HUGE difference, and with even a mild converter (2000-2500 stall, still great for a daily driver) the mild lack of torque in the bottom end with the HO won't be an issue. The F-150 cam is absolute junk for spinning the engine anywhere past 3500-4000.

[zoomie]

of course some nice 275/60/15 tires help with traction tooo

[mrltd]

the 93 tbird cam is nice, pretty sure that's the same as the mustang cobra cam.

Low oil pressure shouldn't really hurt the cam and lifters.

With ported E7s the 93 cam, and a stock HO upper you'll barely hit 200rwhp. A stall converter is a must.

I'm running an explorer motor, XE264 cam and a tune and make ~250rwhp. I think the cam is a bit much though.

[zoomie]

the 93 tbird cam is nice, pretty sure that's the same as the mustang cobra cam.

Low oil pressure shouldn't really hurt the cam and lifters.

With ported E7s the 93 cam, and a stock HO upper you'll barely hit 200rwhp. A stall converter is a must.

I'm running an explorer motor, XE264 cam and a tune and make ~250rwhp. I think the cam is a bit much though.

Thunder chicken and cobra cam one and the same.

[86VickyLX]

the 93 tbird cam is nice, pretty sure that's the same as the mustang cobra cam.

Low oil pressure shouldn't really hurt the cam and lifters.

With ported E7s the 93 cam, and a stock HO upper you'll barely hit 200rwhp. A stall converter is a must.

I'm running an explorer motor, XE264 cam and a tune and make ~250rwhp. I think the cam is a bit much though.

Yeah the cobra cam is the 93 Thunderbird cam. I'm running it in my car right now with a complete 97 explorer engine and 1.72 roller rockers. it's definitely nicer than the truck (explorer cam). And more torque oriented for a larger car better than HO cam, in that regard, but a lower peak HP.

[Shooff82]

If youre looking at spending that kind of money, an aftermarket, dual-pattern cam with a high lift an short duration would be the way to go. Crane makes a "compucam" series(at least they used too). These cams play well with even stock, speed density ecu's. A higher lift an longer duration on the exhaust side is the way go go for small-block fords beacause the exhaust ports are less than desireable even on performance stuff like the GT series heads. Its a good way to go especially with such a heavy sled to get moving. Just my 2 cents.

[zoomie]

If youre looking at spending that kind of money, an aftermarket, dual-pattern cam with a high lift an short duration would be the way to go. Crane makes a "compucam" series(at least they used too). These cams play well with even stock, speed density ecu's. A higher lift an longer duration on the exhaust side is the way go go for small-block fords beacause the exhaust ports are less than desireable even on performance stuff like the GT series heads. Its a good way to go especially with such a heavy sled to get moving. Just my 2 cents.

A XE258 cam has almost same specs as HO cam, but high lift, its an HO on steroids! depedning on what version of the crane 2020 it can be awsome or it can be a dog. but my bets on the comp offerings, ive done alot of research on it,as well as chatted with ppl who have one.