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Topic: B 303 or E 303 cam (Read 1220 times) previous topic - next topic

B 303 or E 303 cam

Thanks for the reply to my previous post. Things are startng to come together now...

So the next question; my engine is a 85 H.O which does not have flycut pistons so I have to watch the valve clearance. However Ford Racing tech says can go up to .500 lift without a problem. I will have to stay with stock valve size and roller rockers won't work. So what are the differences between the B 303 and E 303 cams? I'm using a mass air system so injection/ computer comatability is O.K.

Dave

Re: B 303 or E 303 cam

Reply #1 –
The '85 HO should have valve relifs, have you had the heads off to check??? If it doesn't then you have a '86 HO or '86-'91 SO 5.0. What heads does it have(casting #)???

Anyway in a fairly heavy car like your '56, I believe I'd go no more than the E-303(the B is kinda grumpy). Really depends on what transmission you are using. Even with a mass air setup you'll probably get a a little buck/surge at low speeds with the larger cam(trust me I have experience on this one). As far as roller rockers you can use 1.6s which are the same ratio as the stock pieces.

Re: B 303 or E 303 cam

Reply #2 –
You caught my error, I wrote that the motor is an 85 but it definitely is an 86 with flat top ( no valve relief Pistons). Heads are stock and I plan to do a basic port/ polish on 'em. I'm running an AOD trans non-computer version and 3:50 gears. The car is a daily driver.

The lift specified for the E 303 cam is .498 and the books say this motor/piston/ head combo is o.K. to .500 lift. Sounds kinda close, huh? Valve float would not be a good thing....

Dave

Re: B 303 or E 303 cam

Reply #3 –
If you are gonna use the original heads, valve clearance will not be a issue. That is because the valves are sunk farther back up into the chamber than on most heads.

If you want some really good heads for that engine, do as I did and get a set of the Trick Flow Twisted wedges(they are the only heads that can be used that doesn't have a valve clearance issue with a fairly large cam). I've been running a set on a stock '86 HO short block for over 5 years, using the small Trick Flow cam(its similar to a "B" but with .499 I .510 E lift)...

Re: B 303 or E 303 cam

Reply #4 –
I have a b303, can't wait to see what the idle's like

Re: B 303 or E 303 cam

Reply #5 –
Will E7 heads work on the '86 engine with E303 cam. For me, the E cam seems to be the choice with my daily driver AOD. The reason i ask about the E7 heads is because I have a goof deal available for a set of ported/ polished E7's. They have stock size valves.

Thanks,
Dave R.
 

Re: B 303 or E 303 cam

Reply #6 –
It's been said there is a risk of clearance problems with the E7s on flat tops with anything more than the stock HO cam. I'd clay the piston tops with a head in place to be sure. The "E" does start to open the intake valve at 0* BTC, and closes the exaust valve at 0* BTC, so I would think it would be OK.  A cam like the B that starts to open the Intake 5* BTC(or close exaust ATC) could definatly be a prob.