This is my new project I just had to buy. 1977 k10. Was originally a 400sbc truck but now has a 350. I have a thing for 400’s. If anybody has a decent block in Michigan let me know. It has a 10bolt up front And a 12 in the rear. 203 transfer case and a th350. I already have a line on a 205, hopefully picking it up this week. As it sits now the rockers are rusted out on both sides and so is the bed but that’s ok for what I paid. This build will be a daily driver. So that means no 1 ton axles. My blazer is running good so I thought I would pile on another. I will be switching the grill to a 73-74 soon.CK5
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New project
- Thread starter mark84k5
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This is my new project I just had to buy. 1977 k10. Was originally a 400sbc truck but now has a 350. I have a thing for 400’s. If anybody has a decent block in Michigan let me know. It has a 10bolt up front And a 12 in the rear. 203 transfer case and a th350. I already have a line on a 205, hopefully picking it up this week. As it sits now the rockers are rusted out on both sides and so is the bed but that’s ok for what I paid. This build will be a daily driver. So that means no 1 ton axles. My blazer is running good so I thought I would pile on another. I will be switching the grill to a 73-74 soon.
Are you sure its only a 350? Without measuring the cylinders and/or double checking the numbers on the block, I would be skeptical. I say this because when me and my wife bought our 77 JImmy, we were told it no longer had the original 400 but lo and behold, when I went to rebuild it, something told me to double check the pistons to make sure they weren't oversize. They were oversize alright...the owner misunderstood what the mechanic had told him. It no longer had the original 400 heads, but the Jimmy still had the original block and lower end. I would at least double check the numbers.
The balancer is usually a good way to tell a 400. Look for the notched part for the external balance.
If the 205 doesn't work out, I would look for a 208 or 241 for a daily driver style truck. Then you have a lighter case and better low range. And then it's really easy to go with a 700R4. Not that my opinion matters on your truck.
Should be a fun driver !
If the 205 doesn't work out, I would look for a 208 or 241 for a daily driver style truck. Then you have a lighter case and better low range. And then it's really easy to go with a 700R4. Not that my opinion matters on your truck.
Should be a fun driver !
I'm with you, I like the 400. I built mine for torque and may have overdone that just a tad...I am very very happy with my rebuild on my 400. About the only regret I have is not going with a full roller setup, but I didn't have and extra grand to go towards that. I have close to 6k in it with the transmission, pans and covers and what not. Plus the machine work. Still way worth it.
Depending on where the engine stopped,, I sometimes had a hard time seeing the notch on the balancer with the smog pump and AC belts.
Depending on where the engine stopped,, I sometimes had a hard time seeing the notch on the balancer with the smog pump and AC belts.
I tried to check the numbers when I bought the truck but couldn’t make them out on the back or the front. I’ll dive deeper this weekend when I do all the routine maintenance. I actually forgot to check the balancer. I should’ve known better as I literally just finished my 400 build for my k5. The one in my k5 has a xe262 cam and a 2000 stall converter and will roast the 35x12.50 of a dead stop. I would love to build a twin motor to that one for this truck. I love low end torque.
Just for giggles, have you considered a slightly larger cam for this one? I ask this because I have a 406 in my '72 C10. It once had a Comp 262, I don't remember which version in the nineties, and the 400 soaked it up. I liked it, but it seemed to fall off a little early. It now has a solid roller in it and I wish that I had gone a little larger again. I was too concerned about how quickly it would rev to go bigger, but it will hit 5500 pretty quickly to me anyway.
I can't find the card right now, but I believe that it is 484/498 lift and about 210* at .050. It does have nice low end and perfect idle, though I would like a touch more in the mid range, if possible without hurting the bottom. I have a set of 1.6 rockers that I hope to try this winter, which would give some comparison easier than a cam swap.
I just wonder how your elevation affects it, because at this elevation, I think that a 400 could go slightly larger with the cam than the typical specs list. I bet that they usually test on a 350.
I can't find the card right now, but I believe that it is 484/498 lift and about 210* at .050. It does have nice low end and perfect idle, though I would like a touch more in the mid range, if possible without hurting the bottom. I have a set of 1.6 rockers that I hope to try this winter, which would give some comparison easier than a cam swap.
I just wonder how your elevation affects it, because at this elevation, I think that a 400 could go slightly larger with the cam than the typical specs list. I bet that they usually test on a 350.
You are probably pushing more torque than me, I've got the X4 250H cam with roller rockers, Jegs intake, Moroso 7 qt pan, Pertronix Flame thrower ignition, reconditioned crank, World Products 2.02 heads and had the rods trued up-I saw some funny wear marks I didn't like. 1200 stall on the converter with 3.73 gears and 35x12.50's. I still have some Corvette manifolds to put on and have the exhaust redone. I have to deal with smog still so I couldn't go too far out, but she still passes smog and she will spin the tires if I'm not careful or careful...it's a fine line. She is heavy with all my tools and gear in it though. 6400 lbs with a full tank of fuel.
Don't you have a big block in one of your rigs? How does it compare to your 400?
Yes sir. I have a solid roller cam big block in my '70 K10. The cam is for bottom end power as well. I like how both engines perform for each truck. They feel comparable in general. Both have built 700R4 transmissions but the gears, tire size and truck weights are different. Probably could have put just a little more cam in the big block too, but it pulls pretty good up to 4600 so I don't have the thought of "what if" often.
I do t have a tach so I’m a little unsure where it’s falling off. I would agree it’s probably around 5500. I do have a performer rpm intake and a 1”spacer so it feels like it pulls through the rpms well but that’s just feel of the seat dyno so that doesn’t mean much. I love it though. I have a 750 Holley with vacuum secondary. And a quick change kit. We did some playing around with timing and springs and man the throttle response is unbelievable. I don’t like sacrificing drivability so I can always get more power but it comes with some sort of cost and I’m fine not being the quickest guy out there.
Yeah, I hear you there. Sounds like it's probably just great as is. I just had to ask.
I was gonna add this to my last comment but forgot. I thought I would go with a 205 because of the drive shaft. My 203 has a regular yolk not a slip yolk. But I guess it wouldn’t matter cause I am gonna have to get the driveshaft lengthened anyways I could just have them throw on a slip yolk and run a 208.
Good time to upgrade if you have the cash available. I didn't have a choice when I trashed my driveline. Busted an ear and my slip joint was pretty sloppy so I had a custom driveline made rated at 550hp. One thing I shouldn't have to worry about for awhile at least.
You are going to post pics of your build, right?
Of course…. I picked up a np205 on Saturday. There is a guy up here in Michigan that is closing his trans shop. He’s got t-cases and transmissions just stacked up. I told him to look for a 4x4 700r4 while he is cleaning out his shop. The 205 I picked up has a th350 adapter attached to it so that was a bonus. He had some more of them and some 203’s and a bunch of other crap. If I had the money and space I would have bought a truck load. He is taking the majority of it to the scrap yard. He told me it’s to much of a pain to sell it online and he just didn’t feel like dealing with it. Sad to see these old guys closing the doors. Got a question about the adapter for you guys. The guy I bought the t-case from said the adapter was for a th350. But is there something I can measure to confirm that?
If it has a square, 4 bolt pattern, it's for TH350.
Man, don't let him scrap any 205 cases! If he would strap them to a pallet, I bet that ORD would buy them if he is selling them for a reasonable price.
Man, don't let him scrap any 205 cases! If he would strap them to a pallet, I bet that ORD would buy them if he is selling them for a reasonable price.
I paid $250 for mine
That's a good deal from what I see, because the adapter is with it. I don't know if ORD would pay that, not sure.
I have traded some into them and have gotten less than that, but usually no adapters.
Ok so I call ORD and gave him the number. They are interested in the cases. I called the guy and he’s interested in selling them so hopefully they can work out a deal. Thanks for the heads up.
He had some passenger drop cases and some with shifters. I could have spend a couple hours there going through them all.
Cool! Good to make sure stuff doesn't get wasted!
