Author Topic: C/K series engines  (Read 3620 times)

Offline Ladehak

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C/K series engines
« on: February 17, 2018, 03:00:52 AM »
Hello
What is biggest and strongest engine for C/K series? I found only 454/230hp.
Any special series or special orders?
Rules here in Finland are: you can put 20% more horsepower to strongest engine from factory. 230hp x 20%=276hp. Not enough for any LS engine.
I have K10 1983 6.2D , 6"lift, 35" tires and my dream is old truck with new LS-heart, legally.

Thanks and sorry

Offline Rapid Roy

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Re: C/K series engines
« Reply #1 on: February 17, 2018, 09:51:09 AM »
Welcome to the site
1974 Cheyenne 10 LWB STOCK 350 W HEI /TH350/AC/4 BBL Quadrajet
Mopar by Birth
Chevy by Choice

Offline Henry

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Re: C/K series engines
« Reply #2 on: February 17, 2018, 12:43:10 PM »
Hi Ladehak:
What model year is your truck? What are your country's rules about putting later model engines in earlier model trucks? Can you put a engine originally intended for a car into a truck?

In the 60s and 70s I believe the 454 cubic inch engine was the largest engine option for the GM Chevy light duty trucks (C-10, 20, 30)....I do not know what the largest engine option was for the medium duty trucks but I suspect it was no bigger.

My understanding is that by 1971, all the high performance engines (over 275 HP) sold by GM were ending but these high power engines were offered for cars only. The engines for the 1970s and 1980s were low horsepower engines for the trucks and no special engines were offered that I am aware of...it would be interesting if anyone on this website has any more knowledge about this.

Regards,
Henry

Offline 75gmck25

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Re: C/K series engines
« Reply #3 on: February 17, 2018, 03:00:37 PM »
The 70's and 80's were the smog years, and GM could not figure out how to meet smog rules and still get good performance.  Overall engine performance really suffered.

If you can use one of these LS engines, this might be a choice.  You can alway start out with the truck version of the engine for compliance, and then swap out cam, intake, or whatever it takes to get more horsepower

All this info is copied from the wikipedia page at https://en.wikipedia.org/wiki/LS_based_GM_small-block_engine
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5.3 L
The Vortec 5300, or LM7/L59/LM4, is a V8 truck engine. It is a longer-stroked (by 9 mm (0.35 in)) version of the Vortec 4800 and replaced the L31. L59 denoted a flexible fuel version of the standard fuel LM7 engine. Displacement is 5.3 L (5,328 cc (325.1 cu in)) from 3.78-inch (96 mm) bore and 3.622-inch (92.0 mm) stroke. Vortec 5300s are built in St. Catharines, Ontario and Romulus, Michigan. Another engine variant, the L33, shares the same displacement, but has an aluminum block with cast in cylinder liners, much like the LS1.

LM7
The Vortec 5300 LM7 (VIN code 8th digit "T") was introduced in 1999. It has a cast iron block and aluminum heads, and can be considered the "garden variety" version of the Generation III V8s.

The 1999 LM7 engine produced 270 hp (201 kW) and 315 lb·ft of torque (427 N·m).
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Bruce
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Offline Irish_Alley

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Re: C/K series engines
« Reply #4 on: February 17, 2018, 03:01:58 PM »
how about a cam swap? do they dyno the truck or they just go off of what you say the motor size is? like could you say its only a 305 but in reality its a 355 or stroked out 383? its the same size block as the 305 but it puts out a little more HP and TQ than the 305 could dream about
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Offline 1967KaiserM715

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Re: C/K series engines
« Reply #5 on: February 17, 2018, 05:12:40 PM »
I wonder if you can bypass the 20% power rule with better emission standards of LS engines?

The 6.2 diesel is a decent engine, adding a 6.5 diesel turbo will wake it up, giving decent power with respectable MPG. Just another thought. That would keep you under the 20% mark.

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Offline Ladehak

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Re: C/K series engines
« Reply #6 on: February 18, 2018, 04:12:15 AM »
My truck is 1983
I can use older or never engine, from car or truck. 454 is enough big but problem is HP.
No matter of emission standards( old truck)
I dont need maximum HP, I want new school gasoline engine.
My opinion is: USA made oldtimer  truck or car is not USA made with diesel engine ;)
Diesel is ok for never truck. From 400HP/800TQ
Sometimes they need dyno papers but it is same than toilet paper. You can tuned your engine with dyno and it looks like less HP. Print out the paper and then tuned again to high HP.
If I have engine block which is under maximum HP(I can show it from papers) that is ok for them. They not open engine or do any other big inspection.
I dont want go to swap any parts, yet.
Here in Finland all parts are very expensive and delivery costs, custom, tax from States is pretty high. Thats why I want readyset.
If I could get some documents from "GM" dealer with stamp or sign which prov that 73-87 C/K has been available with 270-300HP engine. Some special edition, dealer edition with GM support or other similar.
Anyone have GM stamp or GM friend and need some small amout money for hobby ;)

Thanks and sorry

Offline 75gmck25

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Re: C/K series engines
« Reply #7 on: February 19, 2018, 03:16:37 PM »
Another option may be to use this L31 crate engine, which is rated at 250 HP by GM (within your +20%) range. 
http://www.jegs.com/i/Chevrolet-Performance/809/12530283/10002/-1

Once you get the engine approved you can swap in a much more aggressive roller cam, and maybe even do some work on the heads so they will handle more lift.  With these relatively minor modifications you would easily bring this engine up into the 350-360 HP range, and it would be very reliable.

Bruce

Offline Captain Swampy

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Re: C/K series engines
« Reply #8 on: February 19, 2018, 07:16:19 PM »
It's pretty easy to get up over 300hp and have really good driveability with the L31. They likely won't be able to tell the difference. The vortec heads are worth 40 hp and it has a roller cam.
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline Ladehak

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Re: C/K series engines
« Reply #9 on: February 20, 2018, 12:31:55 AM »
Thanks
Is that 5.7L L31 better than 5.3L? Of course 5.7 is "old school" engine with long history but maybe 5.3L is "new school" and more modern technic?
And 5.3L ready set is more easy to find, and cheaper?

Thanks and sorry

Offline 75gmck25

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Re: C/K series engines
« Reply #10 on: March 15, 2018, 07:38:18 AM »
One reason many guys in the US use the 5.3L is that its a very common engine in the newer trucks, so you can often find a complete engine in the junkyard for a good price.  Since they were always fuel injected and computer controlled, many of them still have very good compression and minimal cylinder wear, even when they have over 100k miles.  If you can find a complete donor truck in the junkyard, it can be a relatively cheap way to get a modern engine.

Another common solution is to pull both both the 5.3 and the 4L60 (or 4L80) electronic overdrive transmission, which is a really good combination. You can use the complete engine/trans electronic control system from the donor truck, or there are separate electronic controllers available. 

The L31 is an evolution of the original SBC, if that is significant to you.  However, the Vortec heads and roller cam give it much more potential, so its a significant improvement over the Gen 1 SBC.  Whether you want to use the 5.3 or the 5.7 is up to you.

Bruce

« Last Edit: March 15, 2018, 07:40:29 AM by 75gmck25 »