Sorry for a stupid question about cams

well unfurtunately a cam may not be the best thing for you right now. all cams have an rpm range and higher rpm cams have the choppy idle so if you get a larger cam for the coolness of the idle then it will be dead on the low end and it will be dead slow, unless you swapped the convertor to a higher stall like 2500-3000. on an auto is critical that the cam and convertor be match or the car will be a pig.

as far as porting, removing the thermactor bump, gasket matching, and smoothing out the casting will help, but dont go crazy grinding tons of material out as it will make it worse.

Yeah that is a stupid question

Just kidding stock cam is a pretty good cam and will still work good with the mods you're going to do for now. Not too sure I'd go through the trouble chaning it now considering the effort involved and results you'll see but if you are determined to make the swap go with something small. If I were you making the changes you're making I'd look at this, just be prepared to get the right springs for it.

www.lazercams.com part# 2670439 267/267 215/215 .520/.520 110

higher rpm cams have the choppy idle

Click to expand...

Its more the overlap than the size, the above cam will have a chop to it and give good performance. If you do swap the cam get one that has small 0.05" durations and aggressive lobe profile both of these will make torque that's what auto need and don't forget to match stall.

not for nothing but a 110 of lobe seperation will kill low end power in an auto, and 110 is not very efi friendly. I could see that size cam on an auto if the lobe seperation was 114-116 deg.

Not with that small of cam, it'll idle and work just fine. There are few guys running the Comp equiv (35-420-8 270/270 215/215 .533/.533 110) on basically stock motors with great results.

Some reading I pulled off another site:

"For those following along, here's the combo:

'92 LX 5.0 with 150k on it
Box-stock Cobra intake, FRPP 65mm TB, Pro-M 75mm MAF, K&N Panel filter in stock box/no silencer
1-5/8 equal-length shorties to off-road h-pipe to 2.5-inch Super Turbo cat-back
3.55's and T-5

I got a definite kick in the pants a few years ago when I installed the Cobra intake on stock heads and cam. Well worth the effort. I wanted something more, but I didn't want to mess with the expense or hassle of new heads.

The car is daily driven in nice weather, autocrossed a lot, and also open-tracked. I wanted more low and midrange torque to get me out of corners without requiring a shift, and I didn't need it to be a high-winder.

I was encouraged by the results 5.0 magazine got out of a very similar combo in the Sep '03 issue by installing a Crane 2031 and 1.7 rockers...like 40 lb-feet at 3000 RPM (Interestingly enough when they installed Edelcbrock heads on the same cam in the next issue, power fell way off until about 4200 RPM)

Talked to a few folks and went with the Comp 270 HR Buddy Rawls often recommends as a good off-the-shelf cam for stock-head combos with balanced intake and exhaust capabilities. Part number is 35-420-8, specs are 270/270 215/215 .533/.533 on 110 LSA. I installed it dot-to-dot on a Ford Motorsport timing set, without degreeing it exactly.

I installed new Trick Flow valvesprings and a Pioneer balancer at the same time.

Had to deal with some valvetrain noise issues but it's mostly all sorted out now.

The verdict: I got what I asked for. Butt-o-meter says I have WAY more torque even as low as under 2000 RPM than I did before, with a less peaky transition at 3000 than i had with the stock cam. Interestingly seems to run out of breath a little more sharply after 5200 than the stock cam but I can't tell for sure, haven't run it that high too much yet.

It idles just a little choppier than stock, but still mild. I actually would have preferred a rattier idle but I'm not sure I can get that AND good bottom-end.

I'll take it to the track in a couple weeks but I'm not expecting miracles, for a few reasons. The last time I had it down the strip I was running about 101.5 mph but I had a lighter car...no roll bar, stock brakes, light wheels. Now I have a bar, heavier 17's, and heavier front brakes. I also had DR's before and now I don't.

I also don't know if I'll show much improvement on the dyno because the one and only dyno run I have was a little portable deal and due to miscommunication it doesn't start registering until 4600 RPM"