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-   -   Upgrade my stock 350 for torque. (http://67-72chevytrucks.com/vboard/showthread.php?t=755800)

69SCSS 01-27-2018 10:15 PM

Upgrade my stock 350 for torque.
 
My '68 has a 195/260hp GM Crate Engine from 2013 in it. I swapped on a Performer Intake and 1405 carb. It runs good, gets OK mileage, pulls well, hell even spins the tires occasionally. I did a quick GPS 1/4 mile test and it did a high 14 at about 85. Not bad, really. But.... I want it to pull harder.

My real world expectation... I don't really go over 4k rpms, ever. So torque is way more important than hp. I want to upgrade the long block with a cam / lifter kit that will maximize low end torque, and if it runs out of steam at 4500, no worries. I have stock ramhorns and pretty happy with how they sound and work.

I looked at a COMP grind SK12-206-2, (https://www.summitracing.com/parts/cca-sk12-206-2) that seems good. I also saw the COMP CL12-210-2 (https://www.summitracing.com/parts/c...10-2/overview/) that seems good, but not sure that it might be too much for my small stock iron heads. I want to keep with in budget, so $250 for a cam swap is about right. Anyone have any experience with either of these or similar spec grinds for torque?

nikwho 01-27-2018 10:49 PM

Re: Upgrade my stock 350 for torque.
 
I've put the Summit Racing 1103 cam in two 350's now and could not be happier. I currently run that cam with one of the cheap Summit Racing torque converters (2,300-2,600 RPM stall) and could not be happier. I run it with Vortec heads and a Weiand Stealth (two plane, like your Performer) intake and a 1406 Edelbrock carb. That truck weighs 3,640 lbs curb weight, without me. Cam broke in perfectly, even with a couple of hiccups during the break in process. The 1103 cam reports a power range between 1,600-5,200. If that is a little higher than you want your power band to be, the 1102 cam from Summit looks good and has good reviews. It's power building range is reportedly between 1,500-4,000 RPM. Either way, I don't think that you can beat those cams for the money, each priced at $62, or $100 for the kit that includes new lifters, which you will NEED when swapping your cam.

Good luck!

Nik

B. W. 01-27-2018 10:53 PM

Re: Upgrade my stock 350 for torque.
 
The 440 lift cam will give you better low end performance.

nikwho 01-27-2018 10:55 PM

Re: Upgrade my stock 350 for torque.
 
I think that you're doing REALLY well if you're already getting that thing 1320' in 14 seconds from a stop, with an otherwise stock engine and transmission.

69SCSS 01-27-2018 11:12 PM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by nikwho (Post 8171928)
I think that you're doing REALLY well if you're already getting that thing 1320' in 14 seconds from a stop, with an otherwise stock engine and transmission.

Pretty light truck, no power steering, 3.73 gears and 700r4 setup for higher shifts. It was a 14.9, but that is a GPS run, so it could be a 15.2-14.6. Not bad like I said, not great though.

The 440 cam does sound better. The 260 duration should keep the torque peak lower. 278/288 seems high. My cam is a puny 194/204 @ .050 right now at like .400" lift... so any of those will wake it up! :lol:

nikwho 01-27-2018 11:28 PM

Re: Upgrade my stock 350 for torque.
 
The 700r4 will certainly help, with the lower first gear!

69SCSS 01-28-2018 12:38 AM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by nikwho (Post 8171952)
The 700r4 will certainly help, with the lower first gear!

Yea, it has the usual drawbacks but the OD was needed so I could use it long distance. Started out with a TH400 and 2.48 first, but a $200 700r4 in good condition was too good to pass up. They don't like to downshift from OD, but I tweaked it so it will at full throttle.

Anyway, thanks guys for the info! Pulling the truck apart here to paint in the next month or two, so doing some upgrades while I have easy access. :metal:

garyd1961 01-28-2018 04:44 PM

Re: Upgrade my stock 350 for torque.
 
A set of vortec heads would probably do more than a cam swap.

DieselSJ 01-29-2018 05:52 PM

Re: Upgrade my stock 350 for torque.
 
With the SBC that I had in my old CJ5, I used an Isky cam with a 208/216 duration at .050. It had awesome torque.
https://www.summitracing.com/parts/i...7012/overview/

Powerband is wrong in the description - it was done before 5000rpm.

Stryder67 01-30-2018 11:39 AM

Re: Upgrade my stock 350 for torque.
 
Doesn't sound like you'd like to do anything with the exhaust, however don't underestimate what a set of long tube headers can do. Yeah they are a little noisy compared to the ram horns. As far as cam I'd have to vote for the 1102 cam with stock heads. Maybe look at some rockers as well

Tom 02-01-2018 05:03 PM

Re: Upgrade my stock 350 for torque.
 
I've never found a 350 lacking torque. They are gutless HP wise stock but torque? They can tow more then the truck is rated for. Guess I've driven non trucks too much, now that's lacking torque.

nikwho 02-03-2018 06:32 PM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by garyd1961 (Post 8172408)
A set of vortec heads would probably do more than a cam swap.

+1

Also, replacing heads and cam would be a couple of good upgrades to make at the same time! But, that also snowballs into buying a new intake manifold, since the Gen 1 SBC intake won't work on the Vortec cylinder heads.

Richard2112 02-03-2018 06:41 PM

Re: Upgrade my stock 350 for torque.
 
I'm interested in doing a similar set up. Let us know what you decide/how it works out.

Ironangel 02-04-2018 12:12 AM

Re: Upgrade my stock 350 for torque.
 
I did a rebuild on a stock 72 350 four years ago for my 72 C/10 and was looking for a cam for towing an occasional 7000LB tandem trailer. I went with the Lunati Voodoo 256/262 cam/lifter kit, http://www.lunatipower.com/Product.aspx?id=2323&gid=287 and I couldn't be happier! Still pulling like a train! I added an Edelbrock 2101 with the factory 4MV Quadrajet and Hedman long tubes. Bone stock heads and pistons with MSD HEI...PS. 14.9 aint bad! ;)

69SCSS 02-12-2018 11:34 AM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by Stryder67 (Post 8173924)
Doesn't sound like you'd like to do anything with the exhaust, however don't underestimate what a set of long tube headers can do. Yeah they are a little noisy compared to the ram horns. As far as cam I'd have to vote for the 1102 cam with stock heads. Maybe look at some rockers as well

I have 2.5" duals with the ramhorns, and used to have headers. As much as I liked the sound of them, they leaked all the time. The ramhorns are mellower sounding, but seems to not have restricted it too much. Of course with a bigger cam, that may not be the case.

Quote:

Originally Posted by Ironangel (Post 8177632)
I did a rebuild on a stock 72 350 four years ago for my 72 C/10 and was looking for a cam for towing an occasional 7000LB tandem trailer. I went with the Lunati Voodoo 256/262 cam/lifter kit, http://www.lunatipower.com/Product.aspx?id=2323&gid=287 and I couldn't be happier! Still pulling like a train! I added an Edelbrock 2101 with the factory 4MV Quadrajet and Hedman long tubes. Bone stock heads and pistons with MSD HEI...PS. 14.9 aint bad! ;)

Thanks for the suggestion, that's right in the ballpark. I'll be rolling the truck into the garage for disassembly next week (hopefully) and will let you guys know what I wind up with. :metal:

Keystone_Hate 02-12-2018 02:12 PM

Re: Upgrade my stock 350 for torque.
 
Check out Engine Masters on YouTube. They do a lot of comparisons on small block chevys.

Cam comparisons.
Headers vs. Manifolds.
Intake manifolds.
Roller vs flat tappets
EFI vs Carb

All kinds of cool stuff and they dyno all of it.

just something to check out.

LostMy65 10-18-2018 07:01 PM

Re: Upgrade my stock 350 for torque.
 
Updates?

Greasey Harley 10-19-2018 12:35 AM

Re: Upgrade my stock 350 for torque.
 
I just built this motor.
I used 72cc swirl port TBI heads. They make good low end torque and do nothing over 4500rpm
Mtc1 cam :high lift short duration good low end torque
Flat top pistons 9.25:1 compression
Cast iron manifolds, 2.5" dual exhaust with an H pipe
Hei and a Q-jet
That is a low end torque combo. ...at least I hope so. It's still setting on the engine stand.:rolleyes:

LostMy65 10-19-2018 12:30 PM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by Greasey Harley (Post 8367432)
I just built this motor.
I used 72cc swirl port TBI heads. They make good low end torque and do nothing over 4500rpm
Mtc1 cam :high lift short duration good low end torque
Flat top pistons 9.25:1 compression
Cast iron manifolds, 2.5" dual exhaust with an H pipe
Hei and a Q-jet
That is a low end torque combo. ...at least I hope so. It's still setting on the engine stand.:rolleyes:

Good info.
I have 2.5 rams horn exhaust manifolds and don't want headers.
I very rarely drive over 55, and 90% of the time 45 mph max. And I drive a maximum of 6000 miles a year.
The gm goodwrench I have is very low miles, so I'm wanting to do low cost upgrades to make it as best suited as possible for daily driving.

AcampoDave 10-22-2018 08:07 PM

Re: Upgrade my stock 350 for torque.
 
Quote:

Originally Posted by Keystone_Hate (Post 8186053)
Check out Engine Masters on YouTube. They do a lot of comparisons on small block chevys.

Cam comparisons.
Headers vs. Manifolds.
Intake manifolds.
Roller vs flat tappets
EFI vs Carb

All kinds of cool stuff and they dyno all of it.

just something to check out.

Yeah, what a great series. I learned about it from this site.


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