Messin' with a 305...Camshaft

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Ronno6

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I am still contemplating livening up my 305.
Truck is an 84 C10, but engine is a 1-piece rear seal 305, so, unsure of year.
Odd serial # almost makes me suspect it is a crate motor.
Tranny is Muncie M20
Rear 3.73 posi.

I have Hedman 1 5/8" long tube headers and 2 1/4" dual exhaust with Walker Thrush mufflers.
Heads will be either 601's or 416's stock 1.84" / 1.5" valves and maybe some mild porting/polishing work.
Intake TBA, probably a dual plane
Carb Holley 600cfm.

Now I seek input as to cam selection.
As I have vacuum brakes, I need to maintain good vacuum.
Other than that, it will be a daily driver, so not too crazy.
But, I'd like it to go..........
Hydraulic flat tappet lifters.

Summit has a bunch of kits, but I need guidance on specs.
 

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A lot of "will be's" in your post. That means you haven't went down the rabbit hole yet. Toss the 305 and buy a crate 350.
 

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Above ^^^
 

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In all fairness, the setup you’re looking it is as good as it gets for a 305. Go 1.94/1.5 on the valves and you’re there. A good mild cam would be a Comp 12-300-4. Anyway, I think you could make 300 hp if you play your cards right with this, but otherwise I would suggest getting a 350.
 

Ronno6

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A lot of "will be's" in your post. That means you haven't went down the rabbit hole yet. Toss the 305 and buy a crate 350.

I have not purchased the heads,cam,or intake.
I have 601 heads available for $50.00/pr and 416's for $100.00 both probably needing valve jobs.

I KNOW that moving up to a 350 would be the way to go........but I am following the old adage "work with what you have."
Much $$$$ to be spent on body,paint and interior.
I'm just trying to give the pedal on the right a bit more *****..........

p.s. 300 HP would be fine!
 
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idahovette

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I personally would stay away from "company grind" cams. (Summit, Jegs etc.) I prefer Comp Cams because I have had very good luck with them. I think 73c20Jim said it first? YMMV
 

Ronno6

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In all fairness, the setup you’re looking it is as good as it gets for a 305. Go 1.94/1.5 on the valves and you’re there. A good mild cam would be a Comp 12-300-4. Anyway, I think you could make 300 hp if you play your cards right with this, but otherwise I would suggest getting a 350.

Thanks!
Isn't that cam a bit on the mild side?
What are its advantages/disadvantages?
I wouldn't mind going a bit hairier.......
 

DirtyDYT

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Thanks!
Isn't that cam a bit on the mild side?
What are its advantages/disadvantages?
I wouldn't mind going a bit hairier.......

A mild cam is totally appropriate for a truck because you’re looking to maximize torque across a broad swath of RPM for drivability. A lopier cam would probably perform a bit worse than what you have now until it’s up to 4-5k. I can’t imagine driving my truck like I do my Honda.

BIG BLOCK it!:cheers:

Agreed 100%. I’m wrapping up my own roadkill-esque 454 swap C10. Truck, engine, and parts ran me $2000.

And....OFF the deep end we go..........

Can we? Please? :D
 

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I have to disagree with the statement above about Summit cams. Their old school grinds are easy on valve trains and will work fine for a long time. Gotta be tens of thousands of the popular K1102 204/214 cams kits out there.

For your combo, how about the SUM-K00032 cam and kit -- 204/204, .427"/.427". It's part of a cam line Summit started selling several years ago. I suspect they are made by Crane because the specs are identical to the Crane Energizer cams. In fact, Crane has a 10032 cam & kit for $60 more. (Note the P/N similarity.) Not sure what the difference is, but could be Crane's lifters are better.

Of course the SUM-K1101 at (194/204, 398"/.421") would get the intake valve closed a little earlier on the compression stroke for decent cylinder pressure in a low compression engine. It looks to be a close copy of the cam used in lots of 307-327 engines in the 60s-70s.

Finally, the 305HO engine that was used in the Z28 had a "relatively" hot cam that you might want to research. That engine also used a decent set of heads, but you know more about 305 heads than I do. Food for thought.
 

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Friends don't let friends do 305s...
 

Ronno6

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I have to disagree with the statement above about Summit cams. Their old school grinds are easy on valve trains and will work fine for a long time. Gotta be tens of thousands of the popular K1102 204/214 cams kits out there.

For your combo, how about the SUM-K00032 cam and kit -- 204/204, .427"/.427". It's part of a cam line Summit started selling several years ago. I suspect they are made by Crane because the specs are identical to the Crane Energizer cams. In fact, Crane has a 10032 cam & kit for $60 more. (Note the P/N similarity.) Not sure what the difference is, but could be Crane's lifters are better.

Of course the SUM-K1101 at (194/204, 398"/.421") would get the intake valve closed a little earlier on the compression stroke for decent cylinder pressure in a low compression engine. It looks to be a close copy of the cam used in lots of 307-327 engines in the 60s-70s.

Finally, the 305HO engine that was used in the Z28 had a "relatively" hot cam that you might want to research. That engine also used a decent set of heads, but you know more about 305 heads than I do. Food for thought.

Thanks.
Definitely food for thought.

As for heads, both sets which I am considering were 305HO heads.
Both have 1.84" intake and 1.50" exhaust
the 601's have a slightly smaller chamber to boost compression ratio to about 9.6; the
416 would yield about 9.0 but I am not sure which pistons that would require, nor which pistons I have., as I am unsure as to exactly what my motor is......I have been unable to get the block casting #, and the serial number (K0190560) is not indicative of it being the original motor. It has the 1 piece rear main seal, but perimeter bolted valve covers.

I am looking around at 350's and seek guidance on those, but I will start another thread if I cannot find anything out thru a search of the forum.
 
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Ronno6

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Saved a few bucks....pulled a rocker cover and found that my engine already has the 416 heads.
That "just" leaves cam and intake (along with head work....)
 

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