Performance camshaft for stock 305??

[nikwho]

Hello all,
I am trying to not rush my 383 build, which is a 4 bolt block that I am running a Scat cast crank, forged rods/pistons. I am planning on running AFR heads and either a Holley Sniper or EFI Tech EFI system on. Still a couple of grand out and waiting on some machine work to get done. So, as I said, I'm trying not to rush the process. The 305 that resides in my '68 GMC needs to be woken up a little bit. I'm going to install my headers and two 40 series Flowmasters. I've currently got a 1406 Edlebrock on the truck. I am going to run an Edlebrock RPM Air-Gap on my 383, which I could run on my 305 in the interim. My transmission is a TH350 with B&M Transpak shift kit and a 2,300-2,600 stall 10" converter. I'm curious what would wake up this 305 the most with the stock rotating assembly? I was thinking of sourcing some L31 Vortec 305 heads and having them milled down 0.030"-0.045" to bump compression and have larger valves. I've got another project that I can run this 305 in down the rpad, so it won't be a wasted effort. Anywho, any thoughts on camshaftsthat would get the best out of this little 305 with RPM Air-Gap with 1 5/8" Heddman headers ans dual 2.5" exhaust with 600cfm Edlebrock? I live at 6,800' ASL.

Thanks,
Nik

[James the III]

I'd use the 305 vortec heads from a van.. (no milling needed)and then the latest 305 tpi cam
if you use the 350 heads with the larger valves and a higher lift cam.. look at cyl wall to intake valve clearance

[Captainfab]

The L31 is the Vortec 350. The L30 is the Vortec 305. I would be careful milling the heads too much or you may have intake bolt alignment issues. I would just leave the stock valves in the heads. You will have valve shrouding issues with larger valves. Is the 305 block factory roller cam capable? If so I would think about the Ram Jet 350/HT383 cam.

[Tom]

So your saving up for your 383 build and want to spend money milling and installing larger valves in 305 heads? That makes no sence at all. Buy a cheap cam if you must, otherwise stop wasting AFR money on it.
Yes the vortec 305 is a roller block. Factory ramjet 350 cam is puny and not really an upgrade. Perhaps an oem LT1 or LT4 cam, otherwise most aftermarket rollers cost bigger money.

[nikwho]

Hey guys,

So to clarify, I was just kicking around the idea of looking at the local pick-n-pull for some cheap Vortec 305 heads, milling if I must for compression ratio. I am not wantin to spend much money doing this. Just trying to wake this thing up a little. This is an '83 305 truck engine, so it's not a roller cam. Just looking for a decent hydraulic flat tappet cam that will wake it up a bit. No head swap would be fine by me! If a significant improvement would come with the 305 Vortec heads & I could source them cheaply, I'd be game. Anyway, what about a cheap Summit Racing house brand or something in the <$200 range for a cam plus new tappets?

Thanks so much for any and all help!

Nik C.

[AcampoDave]

I was thinking earlier "If it was me I'd just get a cheap Summit 1102 cam kit and put it in there and be done with it.." But I didn't respond until you said it first. A lot of people here know way more about cams than me so I was reluctant to jump in.

[nikwho]

Thanks Dave. I looked up the Summit 1102 cam that you listed. Looks to be a good cam for the smaller displacement 305! I may just go that route. Nice and cheap, which I like! Thanks for your input.

Nik

[Marv D]

Originally Posted by Tom

So your saving up for your 383 build and want to spend money milling and installing larger valves in 305 heads? That makes no sence at all. Buy a cheap cam if you must, otherwise stop wasting AFR money on it.
.

Us Az desert rat boys are sticking together here and offering the best suggestion I can think of... LEAVE THE 305 ALONE! It's not worth the gaskets to start changing ANYTHING unless you bump compression,,, a LOT, and a cam, and better heads, and better exhaust, and a quality dyno tune, and .. and ... and...
.. and............... your $ ahead to just keep saving for the 383 and leave the boat anchor 305 there to get you to work and back.

But that's just 2¢ and just my 2¢,, but it spends very easily

[Captainfab]

Sooooo much hate for the lowly 305.

I would agree with the 1102 cam. That will be good in a basically stock 305.

[Marv D]

I won't say 'hate' CL,, but I'm just of the mind of WHY??? It's a pretty efficient motor with torque (because of stroke) to move a heavy chassis just the way GM delivered them. Screwing with a good thing (throwing $ at it) instead of putting the $ towards the REAL performance motor he's saving for... just makes no sense to me.

That ol saying of ..... Do it nice not twice. comes to mind here.

[nikwho]

Originally Posted by Marv D

I won't say 'hate' CL,, but I'm just of the mind of WHY??? It's a pretty efficient motor with torque (because of stroke) to move a heavy chassis just the way GM delivered them. Screwing with a good thing (throwing $ at it) instead of putting the $ towards the REAL performance motor he's saving for... just makes no sense to me.

That ol saying of ..... Do it nice not twice. comes to mind here.

I'm with you guys as far as not throwing a bunch of money at it. And the saying "do it nice, not twice" is exactly what I'm trying to do here. I could gasket and re-ring a 350 or slap my 383 together, but I'm trying to not rush my engine at all. Putting a couple hundred bucks into this engine is a drop in the bucket compared to the money I'll be spending on my 383 build. I have fun with tuning and tinkering, even if it's not the ideal platform. Was just looking at cheap alternatives to liven up my 305 so I don't feel rushed to finish my 383. I've got the Heddman headers, Flowmasters and Edelbrock Air-Gap RPM intake ready for my 383. The exhaust work would just help get ready for the swap. I also just installed my new aluminum Griffin radiator and installed my shift kit, new torque converter and trans cooler, to prep for the swap. If I did the 1102 Summit cam for $60, plus a set of tappets, I have an extra FelPro gasket set on the shelf.

Food for thought, ive got an extra 2 bolt 350 engine that had 80,000 miles on it. Perhaps I should just spend an extra $100-200 on bearings and rings, run a ball hone through the cylinders, get some file fit rings for the stock pistons. Then I could run a 350 until my 383 is done and sell my 305 long block to fund more of my 383 parts. I like tinkering with the truck (not my daily driver) and trying to not rush my 383 build. I'm really wanting to build the engine right, with all the goodies that I want on it.

[Tom]

I think a cheap cam like the 1102 is a great option for the time being. Its cheap and calms your mind that feels the need for mods, I get it.
FWI, nobody is going to buy the 305 if you go the 350 route. Nobody wants them.

[nikwho]

Originally Posted by Tom

I think a cheap cam like the 1102 is a great option for the time being. Its cheap and calms your mind that feels the need for mods, I get it.
FWI, nobody is going to buy the 305 if you go the 350 route. Nobody wants them.

Well, I ended up selling my engine for $650! Turns our some folks do want them! I'm gonna just press on and get this 383 built!

[AcampoDave]

Just goes to show....Not everybody wants to haul ass. Some people just want to drive.

[Tom]

Originally Posted by nikwho

Well, I ended up selling my engine for $650! Turns our some folks do want them! I'm gonna just press on and get this 383 built!

Note to self, make drive to flag when I sell unwanted V8's. Nice goin!
I bought a 305 for my 79 when I sold it and removed the vortec 350, cost me a whooping $50.

[Malo83]

Originally Posted by AcampoDave

Just goes to show....Not everybody wants to haul ass. Some people just want to drive.

My boat anchor is still running great, i'm at that age where i'm in no hurry to get anywhere, my 305 might not be fast but she's dependable
when that time comes to put her to pasture an E-Rod Ls3 6.2 will be installed.

[MikeB]

What do you know about the 305? The L69 and LE9 both had 9.5:1 compression and decent heads with 1.84/1.50 valves. The L69 had a 202/206 cam, which was bigger than 350 cams (except for Corvette) at the time.

Just noticed you live at 6800 ft elevation. I can say from experience that you'll need a cam that gets the intake valve closed early on the compression stroke. This one would be just the ticket for a 305 in thin air:

Crane P/N 114112, Grind # 2020

Crane's description:
Great for 305 and 350 engines in cars, light and intermediate
trucks with optional gearing. Good low and midrange
torque and HP. (50 state legal in 81-87 car and 350
applications only. C.A.R.B. E.O. D-225-19)

On Crane's recommendation, I ran one in an 8:1 350 when I lived in the Colorado mountains and regularly drove at 7400 +/- 2000 ft. Because of the short duration and tight 104 LSA, it made gobs of low and mid range torque, but would rev to only 4500 RPM or so. (I expect a 305 would rev a little higher.)

If you just have to go bigger, then don't go any wider than a 110 LSA, and preferably 108. This will make for a narrower power band, but with a harder hit, because it would make good cylinder pressure. Otherwise, at that altitude you'll end up with a dog at anything below 2500 RPM, even with the Summit 204/214/112 cam.

[68Gold/white]

Originally Posted by Marv D

Us Az desert rat boys are sticking together here and offering the best suggestion I can think of... LEAVE THE 305 ALONE! It's not worth the gaskets to start changing ANYTHING unless you bump compression,,, a LOT, and a cam, and better heads, and better exhaust, and a quality dyno tune, and .. and ... and...
.. and............... your $ ahead to just keep saving for the 383 and leave the boat anchor 305 there to get you to work and back.

But that's just 2¢ and just my 2¢,, but it spends very easily

Amen! to this!!!
If it runs and has no problems, DON'T SPEND A PENNY ON IT!!!
If a cam lobe is going flat, the sealed power CS274 stock replacement cam would work fine! and is likely the cheapest cam anyone can buy for ANY engine.

There should be a rule on this board, that absolutely nobody can talk about 305's!

[LT7A]

Originally Posted by MikeB

The L69 and LE9 both had 9.5:1 compression and decent heads with 1.84/1.50 valves. The L69 had a 202/206 cam, which was bigger than 350 cams (except for Corvette) at the time.

MikeB, good info. Unfortunately, if I read post #13 correctly, the 305 has been sold. That said, I would be interested in compiling info to get the most out of these little motors. I agree with the comments that say if you are going to build a motor, why not build a 350 for the same cost. But if you have a good running 305, like I do, I want to know what parts might enhance it. If you are up for comparing notes, I'd be happy to start a new thread.

For those who have a negative perspective or experience with the 305, You are more than welcome to your opinion. I felt the same way until I accidentally got one. Some of us have good ones (the factory built them to several different performance ratings) and we are interested in getting the most out of them. Along with that, keep in mind that the thread had "305" in the title, so if you really don't want to talk about them, you can just click on threads that are of more interest to you.

[AcampoDave]

LT7A, I like, your idea, and although I don't run a 305, I do have a 283 with 305 "416" heads on it which do believe have the 184/150 valves mentioned above and are also ported and polished. You're right, a running 305 isn't worthless.
We have good manners around here about not putting down other members trucks, but when it comes to their motor.... apparently... that bit of etiquette gets lost sometimes when it comes to the 305.