javier146

I am looking at buying some new heads for an 84 351w for christmas, Will some afr heads drastically make the 65 car waste more gas than before or about the same? I was just thinkingof installing the comp camI currently have and leaving everything stock except for the performer intake and 4 barrel carb and leave it as is for a coupleof years, Or should i just go ahead and get the heads? I kind of want a machine that is not a gas guzzler and have performance at the same time.

67mustang302

It shouldn't effect the mileage too much, heads/cam/intake will really wake the engine up, and if it all matches should get decent mileage and make good streetable power, but depending on how much you have to start worrying about transmision,driveline, suspension etc

javier146

I don't think it should get over 300 horsepowerall i have in it is the flowmaster exhuast, performer intake, 4 barrel carb currently installed, in the garage i have the comp cam which will be lifted .500 with comp valve springs and lifters, all i need is the heads and I think my mustang will be officially done.

67mustang302

AFR 185's with a decent cam and a good intake/exhaust will make more than 300hp. On a 351 it'll make more than 300hp at the wheels

javier146

supposedly the suspension was rebuilt, not to racing standards, maybe more to stock standards, the driveline is stock, and the c4 transmission was recently rebuilt, the cam is a flat tappet hydraulic competition cam 270h series rough idle in small blocks without having to change torque converter, and with some new heads, do you still see problems with the added horspower, If so what are some other heads I could get which are better than stock ones but not as beastly as Afr heads?

67mustang302

AFR 185's wouldn't be all that beastly on a 351, but if the springs are on the softer side, you'll get wheelhop and axle wrap up like mad. Traction bars should help with it though. The C4 should hold it fine depending on how it was rebuilt, but I'm not an auto guy so I can't tell you for sure. That cam with decent heads and induction will make excellent power, but nothing that'd be considered wild for a 351 on the street. Good parts make good power. You could try to find some GT40 heads, better than the otherstock stuff, but good look in that, they've all pretty much been scavanged from the bone yards. A mild port job on the heads you have would work, but for the money you spend and the power you gain you get back to the "might as well get AFRs." Just build it right the first time and don't worry about it, 300hp at the wheels isn't all that wild these days, as long as your suspension and driver skills are up to it. My 302 is making over 300 at the wheels and it's hardly wild, I don't spin it past 6,200rpm

LCC

You will have no problems with your drive line. Stock street tires will brake loose way before you have any problems with your rebuilt trans. If you do get into something like a drag radial then we'll talk about upgrading...AFR's make good power out of the box and you can always get more out of them later.

67mustang302

Oh yeah, I forgot to add I'm still running the stock driveline and axleswith street tires, no problems. I wouldn't wanna try launching it on stickies though, just to be on the safe side

javier146

then Afr's it is, I am ready to finally finish this 65 and not hear about upgrading it anymore.

67mustang302

There are other heads out there, you might wanna look into RHS 180's as well, or Darts or Canfields. Since you're not all that concerned about power, go for quality and price