ran DD5 with info you gave ,anything not giving i just used stock specs .

 

to get by with the performer manifold add in a 1" or 2" spacer under carb

 

Got a 2" spacer under that already.


I would be really happy with those specs from the DD5. My fuel is a little off in the beginning but after 1300 rpms im running at 12.5-13.4 all the way thru. So im jetted correctly. i just need a new cam for the carb to level out when the pump kicks on. The one guy i talked to told me to put on a holley 750 DP with mechanical secondaries, but im worried about the weight of the truck since holley says their 750 isnt supposed to be put on heavy vehicles, over 3500 lbs i believe. So maybe just get a new cam? those are cheap and ive already got the valvetrain i need. Custom pushrods, roller rockers, stainless valves; 1.655 exh, 2.090 int; double valvesprings.. i suppose it would just be the labor to put it in... so maybe a bigger cam (idle-5500) and a holley 750 DP will be the way to go.. ill look into it, any advise?

 

Yes, Edelbrock.com - Cylinder Heads - Ford FE - Performer RPM 390-428

 

Do you guys think the cam bearings are still in good enough shape i can just drop a new cam in? I have only about 1500-1700 miles on the engine since the rebuild

 

Cam bearings with 45,000 miles on them are usually in good shape . I think you'll be fine ...

 

I would stay away from the 750dp , double pumpers are no good for heavy trucks . i had a 600dp on my 390 for a little and it just didn't pull right . put the 750 dual feed vacuum secondary on and it pulls real hard .

 

I would stay away from the 750dp , double pumpers are no good for heavy trucks . i had a 600dp on my 390 for a little and it just didn't pull right . put the 750 dual feed vacuum secondary on and it pulls real hard .

 

268h is a good cam , if anything swap that performer intake for a performer rpm . to see more power

 

ya e heads seem to be a lot better than plain ol stocks

 

I am not in much disagreement on this but I would want to see the graph on the 2 pieces to make sure the power curve is very similar. The intake has 1000 rpm higher on the range. Makes me think the curve may be considerably different than the cam.

 

If your using double valve springs and if your cam bearing journals is not properly lubed you'll push the lower part of the bearing out. Then you'll have Babbitt metal flakes in your oil. I've know guys use lighter springs at first start up to just break in the cam and which back to the double one's. Doing a good block oil priming helps too. It didn't help also any trying to adjust the rockers lash either. And back in yesteryear they were also hard on rocker arms & shafts. But with roller rockers you shouldn't have any problems their.. Edelbrock heads are limited to max .600 lift cams.. What do you really want a drag street truck. or what. We both have pretty much the same vehicles and motor. But I've have had mind a little longer then you, now is about 34 yrs. This f250 71,72 are like 5,3400+- a few lbs on tires size & gas & your stuff in your truck. Some have the WT. listed on the pinks as mind says 3,400lbs which was great when living in NV. got pass the Wt. fee of 25 bucks..
Any way yeah a DDP 750 would be a mistake for your heavy beast as you'll notice it taking a nose dives as it bog as it kicks in.. I think you should get some books and figure out how to do this all yourself with your own hands as it much more satisfying. if your unhappy with what you have. other then just paying another guy to do the same stuff you can learn. Like field stripping a 16 or a 50 cal with your eyes closed. Yes we all screw up and have to pull a motor back a part cause we all forgot something on a first build. Or having too many cools ones and talking with your bubbies while putting a motor together. But it's fun when you can build your own race or just a stock motor..Try it you'll like it... my 2cents..
orich

 

did one of these engines many years ago with 268 comp cam. we had to port the heads heavily to get it to do what we wanted. the compression was around 10 to 1 or a little more. never dyno'd but was stout engine. lots of work to porting. if heads not ported and opened up alot it will be lucky to make 1 hrspwr per cube. used a edelbrock rpm and it was ported. 750 double pumper with annular boosters. truck was a 73 ford 4wd. 1 3/4 headers. truck wouldn't hook up and kinda scared him, on 33" mudders, 4.10 gearing. engine would turn 5800 rpm pretty easy. lots of valvetrain work to make this happen and pushrods and shimming to get the best alignment to valve tip. never really got perfect but close. truck ran for yrs and eventually sold because he broke to many parts drivetrain, dana 44 stuff. on your combination like mentioned is a little out of wack. do reccomend the 750 vac for sure. if not under full throttle only running 375 cfm. look into quickfuel carbs. probably the best vacume secondary carb right now out the box. look at spec at quickfuel on operation of secondarys on their carbs. engine is air pump and if your restrict it you will not make power you expect. if wanting big power don't run small carb. but if wanting good driver be conservative. really like big vacume secondary carb in 4wds. any questions drop a message. keepin old iron alive one ford at a time.

 

Thanks, ill look into getting one. DO you have a part #?

Orich, i will keep this truck around for a long time because its exactly what i wanted. I will have to get a car first so i can really tear into this thing because right now its my DD. Thanks for your advise, and i agree, i would love to rebuild this thing on my own. Just need to learn a little more. Oh and BTW, i can field strip a 16, 249, 240B and a 50 with my eyes closed

 

Is this what you have? Holley Performance Products 750 CFM Four Barrel Street/Strip Carburetor 0-3310C