kev2369

I have an 87 gt. It has a stock bottom end but it has ported and polished gt-40 heads with the explorer gt-40 intake. it has a cold air intake and a 70 mm throttle body.the clutch fan has been removed and replaced with a electric fan, and there is no air conditioning to kick on. so the motor is pretty free running, but i have so much trouble with it idling. Sometimes it wants to run and sometimes it doesn't. Also, you can go down the road and it idle fine and u may push the clutch and it will die as soon as pressure is let off of the motor. It has a comp xtreme energy roller cam in it (part # 35-351-8), the rpm range is 1800 to 5800. it won't take take gas unless the timing is advanced up to where it idles at 1500. The duration on the cam is .512 with a 270/276 lift. I'm thinking that the cam is too big for everyday driving. Anyone have this same set up with a different cam or have any suggestions on a cam that makes good power with 4.10 gears but nothing stock.... thanks

Grimace5.0

Actually you have that backwards and the duration # is "advertised" duration. Is the car speed density?

kev2369

Speed density? What you mean by that?

kev2369

...Nevermind.... it's late.... yes it is a speed density car. i assume u mean that it doesn't have maf...

P.S.I.cho

do u have the card that came with the cam, cuz the 270 duration is quite big for only .512 lift im thinking thats the "advertised" duration too at 50* it is probly around 228 duration? unless u got a killer cam in that car, i dunno without seeing the card or getting the full specs off the cam, my car has a .512 lift with a 228 duration and it idles alright, but it is a MAF car with a chip. with speed density u might not be getting the airflow u need for the cam, i dunno tho some one around here might help u better then i could

Black Snake

You cant go too big of a cam with speed density, your going to run into alot of problems with drivabilty. Go Maf and get either a B-Cam or E-Cam. B cam is really choppy and sounds killer, buts it not smog legal, E-Cam is the best all around Cam.

Best is a custom grind cam but if your funds dont allow for it go with one of the Ford racing cams or trickflow.

stanglx2002

I was looking at the crane 2031 cam for my car and thats about what you are looking for.

Grimace5.0

Like BlackSnake said, speed density cars are real "picky" when your talking cams. What are the goals for the car? Daily driver? Weekend warrior? Track car? Take the woman for ice cream on friday night? Any upgrades you *plan* on making in the next year or so?

P Zero

Youve got a vacuum leak somewhere. Your car should idle just fine with that cam. With my 1.72 rockers I actually have more lift than your cam, with the same duration (more or less). I have NO problems. Ive also run, in a flat tappet 302(non H.O.) .496/.510 lift with 280/292 duration, it would idle lopey as hell and would need to idle right around 1K but it would never stall.
-P.