Hello friends ,so any of you that have looked at my threads know i am building a very respectful 69.5 grabber clone for street/ strip use.My goal is the fine line of having a car that is built for the track but i can drive it to the track and race and still drive it to a car show ect. I have been talking to a fellow Canadian ,Richard (valleyracer) from this site about my engine and what i want out of it ,it is his opinion and i respect, that my combinations of parts and wants may be not on track to meet my goals. I have 69 MEXICAN BLOCK 302 that i plan to strock to a 347,im going with stock heads that have been ported well on intake and exhaust with new stock valves with aftermarket double springs,10 :1 forged piston from a after market proformance stroker kit ,now the question ,my cam choice i was going to go with a 512 lift and a 280 duration , Is this not enough cam for my 347 stroker that i want to drive to the track?. Valley racer feels that cam will max at 6200 to 6500 rpm and my 347 will want much more. next question ,what intake ,i have two in mind 289 torker or victor jr or any other suggestion, im also planning on using a elderbrock 750 or a holley 700 double pumper, for exhaust hooker 6208 with 2 1/2 inch coming out at the rear tires,ford 9 inch with 4:11 possi ,Im building a poor mans go fast engine. I would like to here any good suggestions for my engine before i put it together threw this winter your opinions are wanted ,if im going to build it ,i want to build it to match up well and proform ,remember (Steet/strip) coen c4 tranny 3200 stall Outlaw Jimmy2gates
I think with the stock heads on there you should plan a powerband that ends at around 6000rpm and no higher. I had a set well ported, larger vlaves and they still stopped flowing at about 6200. You have some nice parts going on there why limit them with the heads?
I agree. your heads are what will limit your motor. Im running a ford motorsport f-303 (wich is close to your cam specs) cam and stock well ported 1.65 2.02 valved head. Its only a 302 but it was peaking on the dyno at 6200 rpm. On the 347 that will lower your power band of what the cam is made for. As for intake, if you stay with those heads you are beter off with a peformer rpm or stealth intake. a 700 cfm carb will more than likely be to big for that motor. i run a 600 holey double pumper and on the dyno it was pefect as indicated by the manifold vaccume. you would probly be best with a 600 or 650. now if you want room to grow then get the vic jr intake and a 700 cfm carb. the 750 is just to big for motors under 400 cfm. also the 750 has idle adjustment screws on the secondarys and on a small motor its really hard to get it to idle right with out stumbleing when you give it gas.
2.02/1.65 in a stock 289/302 head? HOW? I was pushing it with 1.94/1.60's WOW. those must be shrouded and tight
Yes the heads are going to limit it. If you only have the iron heads budgeted, then I would think about using an RPM air gap. Remember that the 347 is going to give you more torque down low than a 302 would and I would build it with that in mind. You are certainly going the right direction with the Mexican block and the cam seems right on to me for this build. The torque converter may be a bit high for this build though. With this I would also consider a 650 for a carb. Have you done the heads yet? I'd wager to guess that it's almost a wash between getting a used set of aluminum heads vs rebuilding and porting the heads you currently have. Just a thought, but I think you'd be ahead in the long run to plan the aluminum heads early in your build. There are many advantages to later model head technology that you just won't get with the original stock style heads. The heart shaped combustion chambers, the superior heat dissipation of the aluminum, the placement and style of the spark plugs, and the port shape are all advantages to the aftermaket heads. If you do go with an aftermarket head, then I'd suggest that you go with the Victor Jr and a 700 Holley. Just remember that you need to match the entire package...that's the key to a great running quick motor. As always, the views expressed in my post in no way reflect the views of the board...and are subject to change for no apparent reason.
allan root heads Ok ,guys my heads are a problem i quess ,i noticed on craigs list a set of Allan roots heads for sale ,used but in very good shape ,complete roller system ,will this help and should i buy now ,i think i can get everything for 900 us ,need opinion now, cheers 2gates, it comes with roller rockers ,super heavy springs ,girdle ,the works i believe
You will want a Holley carb... bigger than 700. The Vic Jr intake is cool. I ran the T289 and 700DP on a 306 and it was perfect for the street. I think it will be too mild on a 347 with track aspirations. I'd think at least the Vic intake. The 700DP would probably work fine, but you could go larger. The cam is not enough either. It is smaller than what I had in my 306, and a 3200 converter would have been perfect for my combo if I had an auto. Power came on about 2k, came on strong at 3k. This was with max-built 289 heads. The car was fast and would run near 7k. With a 347 though, you will be limited. If you are set on stock castings, then start with early 351w castings. Otherwise use aluminum. Personally, with 347 cubes and 3200 converter in a Mav, I would: 351w ported heads or better aluminum. Vic Jr 750DP Comp 292 or aggressive XE cam (Solid cam would be awesome if you were up for it) 10:1 with cast heads, 11:1 with aluminum 6208s All this in a light car like a Mav and 4.11 gears will move out nice for a street/strip car. If you go any milder, don't use the 3200 verter and 4.11 gears. It will drive like a dumptruck if the engine can't rev fast and utilize the gears.
Vic intake on stock heads? Really? I thought that manifold was 3500-7000 range. Way beyond stock heads, even well ported. I like the solid cam and would recd the 282s for the dual activities of street/strip. I love mine.
You gotta realize that there was a time that you couldn't get aftermarket heads for a 289/302! Believe it or not! And during those dark ages, there were scary fast 289s and 302s in existence. They were running ported stock heads with big valves, and they would pull to 7500+ rpm. I am old enough to remember those days. I am surprised that you're surprised that stock heads could do that. Maybe I shouldn't be with all the brainwashing the aftermarket does to folks nowadays. Edit: Heck man! You're older than I am! Wassup with that?
I feel old now! My outgoing combo is 306 kieth black FT with D0OE 351W heads 194-160 valves ported and shaved 40thou for comp ratio 10.25 to 1 Victor Jr port matched 650DP Holley with mild cam(no specs at the moment) C4 with TCI 4200 converter 9" 456 gear run a traction bar only 110mph @ 12.06 best 60ft 1.58 So this is old school tech for sure but bargain build runs pump fuel 94 octane! Any Questions? Richard
Hmm, was this for me? A Vic intake with stock heads will be a slug in my opinion. I ran 1965 289 heads, ported to an inch of their life and chevy valves with a big crumpy solid cam and a predator and went 12.25. I know it can be done but my heads were dead at 6200. Edelbrock says that manifold is good for 3500-7400 rpm and in my opinion that does not equal stock heads. I don't think I am brainwashed at all. In fact, it took me several years to finaly let go of my "cherised" RHS heads. Edit: Jimmy mentioned stock valve sizes, not 1.94/1.60's that may help the manifold. Also he did not mention 351w heads which would be a bit better as Valley stated above.
