CAM questions

[dave harris]

Does anyone know the spec's on the original cams used in the 289 engines? I've checked the few books I have but don't seen any spec sheets - -

Thanks [img]/ubbthreads/images/graemlins/help.gif[/img]

[David York]

According the book How to Power Tune Ford V8 “ The stock 289’s of mid 63 to 68 had a 252 deg duration valve lift .380” for the exhaust and .368” for the inlets. Events where inlet opening 16deg BTDC and closed 52deg ABDC, Exhaust opening 70deg BBDC and closed 24deg ATDC

Then the Hi-po 289 was a mechanical of the same spec but lift was increased to .457”

Of course this probably has nothing in common with the cams run in the 289’s in the first GT’s!
[img]/ubbthreads/images/graemlins/tongue.gif[/img]

[Ron Earp]

I think it would be very interesting to build a 289 engine to exact GT40 race specs and see what the power actually comes out to be. My guess is that the modern version will be lower due to changes in SAE horsepower ratings and general inflation of anything race related plus 1960s inflation of hp ratings - that is, if everything is built to 1960s specs.

With modern flowing heads, roller cams, springs, etc. I'm certain you can get a good bit more power from the same size motor than you could back in "the day". But, to build one exactly as done in the 60s, GW heads, exact cam, etc. would be a cool experiment.

Ron

[dave harris]

Thanks Dave, I had those specs - I'm just trying to see what type of lift and duration they used with webbers in the original GT-40 back then as a starting point. I've talked to a number of engine builders that have said if I'm willing to rev the 289, they have seen 400+ hp at 7500 rpm fairly easily and could run it on pump gas (with modern heads, solid roller cams and lighweight rotating assy.).

I'm having the block mag'd and sonic checked now - we'll see!

[Alex Hirsbrunner]

Hi Dave,

Try this link - http://www.fordsmallblock.com/PDF/g-2.PDF

It includes the C7FE-A Lemans cam

Regards,

Al

[Ron Earp]

Very nice find! The lift isn't too much really, given some that are used these days. The duration seems long although it isn't the same comparison as specs we use now at 0.050" lift, correct? What type of lifter is this cam used with?

[Jac Mac]

Hi dave.Have a new c7fe-6250-a.Could have a duplicate made if your desperate, try :maier racing, ca: if they are still active. Timing etc is, @ 0".lift 52 btc/86abc[in],82bbc/42atc[ex].@.100" lift 6btc/30abc[in],40bbc/4btc[ex]. Dur318in/304ex. Valve lift .510"@ 1.6 rocker ratio.Ran this in my 302 [Boss] which made it fairly peaky 4/8000 rpm. regards jack.

[dave harris]

Thanks everyone! Knew you guys would have (or find) the information!!

Jack - - If I can't find a modern grind that suits the goal, I'll send you a PM!

[Jim Downard]

I'm building a 289 for my car thats going to stay a 289 (O.K. bored .030 over, but not a stroker). I contacted AFR Tech and asked their opinion on heads. Result, the AFR 165. Told them I was going to turn some rpm, still told to stick with the 165's. I then contacted Reed cams in Georgia and gave the the general specs on what I was building. 10:1 cr, AFR 165's, Webbers, and that I wanted to turn around 7500 rpm on the rare occasion. The cam they spec'd for my motor was as follows: Solid lifter, flat tapped with duration @ .050 of 240/245 and a lift of .523/.524 with a 110 separation. That's very similar to the cam profile in my Cobra only it's running a 393W stroker, and the lift is .544/.541 the duration is nearly the same, but it is a hyd. lifter flat tappet cam. I did the run on the dyno 2000 and the curve does run out to around 7500. Now to get those pistons, good rods, stud girdle, and such so she won't fly apart.

[dave harris]

Hi Jim,

What type of HP do you think will come from this setup?
Also, I'm a bit surprised at their recommendatin of the 165's to turn 7500 rpm - even on a little 289 - would have thought that the 185's would breath much better up there!

I'll be keeping this a 289 as well - plan is to internally balance - use the 289 crank - slightly longer rod, custom pistons, stud girdle, convert to solid roller cam, aim for peak HP at 7400 peak hp with shift point @ 7500 & rev limiter fully on @ 7800 - 8000.

One engine builder even felt that the Edel Vic Jr heads would be preferred, but that volume seems too high to me for the 289 unless you're spinning it to 9000!!!!!

anyway, will be an interesting experiment!

[Jim Downard]

Dave,
I'm being told that hyd. cams of any type aren't going to get you up over 7000 very well, especially hyd. rollers. The ramp on the cam is so steep that at higher rpm, I'm told you can begin to expect vavle float. Also, AFR suggested the 165's as the 185's won't provide the necessary port velocity that is desireable. I'm running webbers so AFR also thought the 165's would be more beneficial there as well. I always used to think that bigger is better, but I'm finding now that a balanced package is the ticket. Make sure the components work together. Anyway, I'm looking at a little over 440 hp on desktop dyno runs. HP peak is between 6500-7200.

[Alex Hirsbrunner]

Hi Ron & Dave

C7FE-A was a mechanical flat tappet cam. Note that this cam is currently reproduced and available from Holman Moody @ (704) 583-2888.

Also, Comp Cams produces modern versions of the (289 271HP) C30Z-C cam in both hydraulic (flat tappet) and mechanical versions that retain the sound of the original with improved performance. You can find them under the nostalgia and nostalgia plus listings here:

http://www.compcams.com/Technical/Cu...HTML/68-75.asp

I recently replaced an original C3OZ-C with the hydraulic Comp Cams version and I am very happy with the improved performance, sound and the maintainance free aspect. According to my GTech, peak power is at about 6250 and starts to fall off rapidly after 6400. This for the following combo: 0.060 over 289, Canfield 54cc CNC chamber heads, Performer RPM, 650 Speed Demon, 1 5/8" shorties, 9.25:1 CR.

Regards & Happy New Year to all,

Al

[Ron Earp]

Hi et. al,

I sort of figured it was mechanical flat tappet. However, here is where you can improve nowaday - use a roller solid lifter which will allow quick ramp profiles on a roller cam and really hold the valve open. And, you can get better valve springs these days to avoid problems above 7k. Dave, I think you can simply do better these days using a solid roller cam, more lift, more agressive, and get more power from the motor if you like.

I don't think I'd be trying to attempt 7k plus with a hydraulic cam, or even much over 6500, unless one can procure some hydraulic lifters made for that sort of thing and I don't know if they are available or not. Might be, I didn't look, I wanted that mechanical lifter sound.

R

[dave harris]

Hi everyone,

I think there is some confusion here - I've NEVER intended to go hydraulic in any form.

Original intention was to stay with solid flat tappet, but was convinced by numerous engine builders to convert to SOLID roller cam (perhaps the term "solid" instead of "mechanical" is confusing people!) for the improved profiles and the ability to better tailor the valve timing.

[Jim Downard]

Dave,
Reed Cams in Georgia will make you a custom ground cam to whatever specs you require.