How much lift can I get away with before I run into problems with a stock 84 model 302? Any suggestions on duration? This will be a mostly street driven car, with an occasional strip pass. I want a "lumpy" idle, enough to make it sound good, but not so much it won't idle. I'm not planning on screw in studs and roller rockers, just stock valvetrain for now.
I think you have the pedestals in 84 heads... Correct? If so, there are several inexpensive kits out there to make your rockers adjustable. These kits also use a guideplate that does not require hardened pushrods. I think you have to switch to a slotted rocker (budget) or roller rocker (money). The duration doesn't matter as much as lift when dealing with stock heads. You can get away with as much as 220-225 duration at .050" with an auto tranny (no stall). I wouldn't get less than 212-215 to get a bit of lope. 218 is probably about perfect for stock tranny. Much more and you will wish you had more gear in the rear. LCA should be kept 110 to 112. Lower being the lopy'er. I have a 218/110/488 Lunati going into mine, but I am worried about that lift rating. The rockers should have enough slot to work without binding, however the push in studs are the weak spot with so much lift. You don't have that, so you only have to worry about having enough slot in your rocker to keep from binding on your fulcrum. Comp makes a cam with the same specs, but less lift. 218/110/456 IIRC... That would be a very good one IMO. I got my Lunati dirt cheap, otherwise that was going to be the one I used. If the subject of split duration comes up, remember: They idle rough, as opposed to a rythmic lope of a single pattern. This can affect your drivability until you make your upgrades. It also means that the cam will be effectively smaller to stay within your limitations. Good luck Dave
I used to have the Comp Cam, that Ratio411 is refering to, in myold "79 302. Had a slight lope and tons more torque than stock. Made power up to about 5200 or 5500rpm(can't seem to recall) with pretty much stock '69 head(took out smog bumps and converted to adjustable rockers) Simular cam to some of the H.O. cams if I remember correctly(would be a first). Car ran 13.77 @96mph in the quarter with this, a 1850 holley, action plus intake, manifolds, 3:50 geared posi and 24" radials(and closed exhaust). Good around cam. Had a nice idle, excellent torque, decent top end and better fuel milage than stock...good on all fronts!
I'm not sure about the pedestals, I haven'n pulled the valve covers...Here's the specs on a cam I was thinking about... Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 278/290, Lift .498/.527, Ford, Small Block, Kit heres another... Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 276/286, Lift .471/.471, Ford, Small Block, Kit I'm leaning toward the second one, what do ya'll think?
I'm not sure what the limit on stock springs is, but I'd be surprised if they worked in combination with anything over a .49X lift (and that might be pushing it). If I was going to get new springs anyway, I'd go for the first one.
My post assumes new springs. Stock springs are junk and just waiting to wipe your lobes! The concern comes back to the slot limit in the rocker. If the slot binds due to lift, you will wipe your cam. Stock slots and studs need to stay under .500". Some folks say under .470" That is where I was coming from. Further: To judge your cam duration and how it will work with your gear and stock converter, you need to know the duration @ .050" lift. You listed cam specs with advertised duration. A cam with 286 advertised duration can have 220 degrees at .050", which is perfect for mild gears and converter. OR it could have 245 degrees at .050", which won't run in gear with a stock converter, and needs 4 something gears to get out of it's tracks.
I have a small howards cam in my driver real short dur but right at .500 lift split dur and lift 114 on center. stock, springs ,rockers and studs worked ok.but I did change the springs and rockers after I got some money saved up.Another one of the cams I liked was a comp dual energy got that from nortern auto parts catalog
Heres a full rundown on two I like the specs on;http://store.summitracing.com/partdetail.asp?part=SUM%2DK3601&N=400304+4294925232+4294861490+4294887598+4294908331+4294840126+115&autoview=sku http://store.summitracing.com/partdetail.asp?part=SUM%2DK3600&N=400304+4294925232+4294861490+4294887598+4294908331+4294840126+115&autoview=sku This will be more a cruiser than an all out street/ strip car, more for sound and low end torque than high rpm hp.....
I'm going to butt in with a quick question, I have a .499/.510 Trick Flow Track Heat Stage I camshaft. Specs at: http://store.summitracing.com/partdetail.asp?part=TFS%2D51402000&N=115&autoview=sku I have 1.7 Full Roller Pedestal mount rockers, provided I use the correct pushrod length, am I going to have issues? (on a factory E7TE head, no screw in studs, etc) (89 roller block)
Just my experience with the summit cams they weren`t really impressive. Stick with the name brands.Cranes Z cams have nice numbers if price is the concern my howards cam and lifter set was $104.95 got it from competition products could give you there # if you want it.
The .498/.527 will be a little better for cruising. However, the .477 camshaft is pretty nice also. Either one will get you the results you're looking for. Both will have plenty of low speed grunt and will have a nice sound to them. I would go with the .477 cam simply due to the lift numbers with stock rockers. You won't have to check fulcrum clearance. I would HIGHLY recommend getting the correct valvesprings & retainers for this camshaft also. Stock springs are just asking for trouble. You need to check with Trick Flow or Summit to see if the lift figures are calculated with a 1.6 rocker or a 1.7 rocker. If the .499/.510 is calculated with a 1.7 rocker then you "should" be ok. If it is calculated with a 1.6 rocker then your actual cam lift at the valve would be .530/.541. There you might have a problem. A camshaft doesn't give a damn what name is on the box. It's all in the numbers.
The Summit cams actually are name brand... They are made by TRW and sold to various companies. The same exact cams go to Edelbrock and get put in fancy boxes with names like 'Performer RPM'. Same cams, different boxes.
The carbs are from TRW too... TRW bought Federal Mogul, who bought Carter, who made the carbs originally. Most of Edelbrock's stuff is made by someone else and gets their sticker on it. Heads and intakes are about the only thing they actually make themselves.
