Cam selection

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PaulRM

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I am in the process of rebuilding my slant and want to "up-grade" the cam for a bit more wallop. What would you suggest for a cam to go with:
Slant six (225 cu.in.) 1970 block bored 30 over and the crank turned 10/10 under. Will have a 390cfm four barrel (as soon as I can source one at a reasonable price...{any assistance here would be appreciated}) as I have the intake. Exhaust manifolds have been split and welded so as to be able to run dual exhaust (two collectors). New timing gears,chain, oil pump, pistons and rings, new bearings. Head was done with new exhaust valves and checked by the engine rebuilding business; shown as good including being trued up.
Again, it is the cam and lifer combo I need help choosing. This will not be a race car but rather a general cruiser. At 55, this is also probably the speed I will be driving it on the highway. It also will have the stock rear end for a slant six car.
Thanks in advance for any and all information you may wish to input here.
Cheers Paul
 
Erson 270 stock lifters. You will be happy with 2.25 exhaust with H or crossover pipe. Then Happier still with .100 off the head and 1.70/1.44 OS valves from Engine Builder on Ebay.
Good luck and Happy Slanting,
Frank
 
I'm in the process of picking out a cam for my slant also, if your not planing the head any or bumping your compression somehow, I'd go w/ Ersons 254* cam. Its also been suggested to me to get an Erson 254*/244* reverse dual pattern cam, that Doug Dutra to came up w/. Seems slants like a little less exhaust duration. Doug has said this cam works very well.

You can take up to .100 off an untouched head, safely. If you do that and get bigger (1.70 and 1.44) valves I'd go w/ the 270*. I have been looking into cams for the slant for awhile now, and the 270* was what I wanted, but since mines going to be more of a daily rig, I'll be going w/ the reverse dual pattern listed above instead though for a little better street manners and some lower end torque.

Also it seems Comp cams has given out slant cams w/ misaligned oil passages, and I've been told the equivalent Ersons perform better anyways. Honestly, I haven't run all these cams. I've only read alot. The suggestions I made are based on suggestions from the ppl that have run them though. Hope this helps.
Dietz
 
Thanks for the info.. Up until now, I have never heard of Erson cams. Seems like the 254* would be appropriate for what I want; what with a stock head and stock valves. I didn't read where either of you are running a four barrel carb. on your slants. I trust the 254* is a good overall match with the four barrel carb. Would the new cam come with new lifters? Actually, my stock ones don't look too bad at all. Lastly, is Holley the only one you can think of that offers a carb. in the 390 to 400 cfm range? I'm ready to "bite-the-bullet" price wise if I need to, however more options may be more beneficial.
Have a great New Year.... Paul
 
270 likes the 4 bbl. 254 wants the 2 bbl. honestly you would be happier with the 4 bbl if you massage the head. This is your choice. I run 1bbl 2bbl and 4 bbls on my slants. I daily drive and race them.
Frank
 
Here,s a Holley(390)I believe??Just got this car and really have,nt tested it out.But I do know the PO bought the clifford 4 bbl. intake and headders,dual exhaust.The holley was brand new out of the box.I guess I should start reading the info. that came with it.LMAO!!Don,t know if he changed the cam?If you look in the picture,you,ll see where the springs are attached.Major vacuum leaks.PO did,nt plug or block off?Still shakin my head??

66 dart 2.JPG


trim 018.jpg
 
PaulRM said:
Thanks for the info.. Up until now, I have never heard of Erson cams. Seems like the 254* would be appropriate for what I want; what with a stock head and stock valves. I didn't read where either of you are running a four barrel carb. on your slants. I trust the 254* is a good overall match with the four barrel carb. Would the new cam come with new lifters? Actually, my stock ones don't look too bad at all. Lastly, is Holley the only one you can think of that offers a carb. in the 390 to 400 cfm range? I'm ready to "bite-the-bullet" price wise if I need to, however more options may be more beneficial.
Have a great New Year.... Paul
Click to expand...

Go to this link for Erson cam info: http://www.slantsix.org/forum/viewtopic.php?t=28993

Always use new lifters with a new cam.
 
Thanks guys for all the great information. I have been reading off the sites mentioned, and I am either going with the 254* or 270* cam. with new lifters. As I was reading, I noted that the slant six guru Doug D. even suggests a custom grind of 254* intake and 244* exhaust. Maybe I should stick to the off-the-shelf grinds though seeings how I am no expert in this field. Any ideas on if I go to the 270* should I be looking at a larger cfm carburetor to match? I believe the dual exhaust (stock size) should still handle a larger degree cam and carb combination.
I am leaning toward a cam that will "come-in" at about 1000 to 1200 rpm and have a power band through 3800 to a maximum of 4000 rpm's. Anyone out there have their car dynoed with a four barrel, larger cam and dual exhaust. Maybe what special head work would need to be done. I'm shooting for the slant to make around 200 hp without any turbo or nitrous. Seeings as how a stock slant of the 1970 vintage is rated at 145 hp.
Thanks again and I look forward to any information. Cheers Paul
 
Actually the slant is 105 HP by todays method of caculation. As for the cam selection Dougs reverse grind patterns should work Great. You wont need any more carb for your application than the 390 Holley....I use the 500cfm Eddys but I just like them better than the Holley.
With the previous post I described that .100 off the head and 1.70/1.44 Engine Builder valves with a mild bowl hog type of port and polish should get you where you want to be. Please note that the engine may have all ready been rebuilt and you should CC the head and report back before just cutting off .100.
PM me if you want to.
Frank
 
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