Crate engine swap advise please?

[MadOgre]

'73 C10 Cheyenne Short Fleet, 2" front spring drop/5" axle flip drop w/ Caltracs traction bars, 1973 350ci base timing is 12* BTDC, HEI w/ 10* Vac. Adv. and 20* centr. blu/ylw springs, Vac. Adv. on carb mani. port, Eldelbrock 1406 98 primary (stock) 95 secondary (stock), 6557 rods, 8" springs), Holly Contender, Cam, '74 882 heads 76cc 1.94/1.5, 1.5" OD header 2-7/8" collector, 142-148psi dry comp., dual exhaust (no crossover), th400 w/ shift kit, 12 bolt Eaton posi, 3.73 gears, 28" tires.

Did your motor crater ?

 

[MadOgre]

Ok with these comments then all future talk about gas mileage is foolish. Just saying. The truck has the aerodynamics, big word, of a brick. You just need it to run good, be efficient, be reliable and pass everything but a gas station. Torque is what you want. You have the right gearing.

I like that "Everything but a gas station" LOL

 

[Joe383]

The 383 will probably get the same gas mileage if not better due to it having a smaller cam. Larger motor don't always get less fuel mileage. I use to be in to bronco IIs and swapping out the 2.9 for a fuel injected 5.0 usually increased the fuel mileage by about 3-4 MPG. I would go with the stage 2 vortec motor if it were me. I have a very similar motor and I love it. Its in my Camaro now but is getting swapped in to my truck in a few months. The second motor will get less mileage than the vortec and not drive as good due to it having a larger cam and weaker heads. It makes less power with more duration. You want to make as much power with as little duration as you can cuz it will kill low RPM torque. Here is a clip of the motor going in to my truck soon after I installed it in my Camaro. It is very similar to the stage 2 motor.https://youtu.be/NWU3ZqmDS08

 

[Joe383]

The stage 2 will require a stall converter just so you know. It will probably be ok with out one but you will not see the full potential of the motor with a stock stall. I would go with a 2,300 RPM with that cam. The motor they have pictured is not of the motor they are going to send you. On my motor I have to have my timing at 16* base timing at idle. It axially likes 18 but I am afraid of it being too much at the top end and will be installing 18* total advance curve kit in so I can run 18* at idle. That's my timing with vacuum advance disconnected at 750 RPM. That video my timing was at 20* and was before I checked it with a timing light

 

[Green79Scottsdale]

Did your motor crater ?

I was wondering that also...

73 C10... does your current motor run? If so, good? You just want more power?

After looking at the specs on your motor, some better heads and a cam that you actually know a little about would move you forward very nicely. I would do a compression check and leak down test to begin with. If those pass, throw some better heads and a nice cam at it. Maybe an intake manifold too, I don't know what a Contender is. Dual or single plain? Heads, cam, and an intake will easily be way under your $2500 budget.

edit: Hell, maybe even just a new cam would be sufficient too. Biggest thing is figuring out your current cam specs. Know anybody an indicator that can reach down into the lifter bores to measure the actual lift on it? A degree wheel with an indicator can give you the duration of the cam also.

 

[MikeB]

A ram jet 350 cam would be a good swap for this motor but I don't know if the stock valve springs will handle it.

The RamJet cam uses stock Vortec valve springs P/N 10212811. But it does use 1.6:1 rocker arms. The same cam and springs are used on the HT383 crate engine, but with 1.5:1 rockers.

My truck's 9.4:1 355 uses that cam with the revised LS7 roller lifters, 1.5 rocker arms, and a stout GMPP single roller timing set with Renold chain. Intake manifold is a Weiand 8121, carb is a 600 CFM Holley 80457SA. I also used GM intake manifold and valve cover gaskets. Not cheap!

Haven't fired it up yet, but I'm looking forward to lots of torque from 1500-4500 RPM, with peak horsepower at around 5000 RPM. That torque should help pull my truck's 2.73 axle.

 

[MikeB]

A ram jet 350 cam would be a good swap for this motor but I don't know if the stock valve springs will handle it.

The RamJet cam uses stock Vortec valve springs P/N 10212811. But it does use 1.6:1 rocker arms. The same cam and springs are used on the HT383 crate engine, but with 1.5:1 rockers.

My truck's 9.4:1 355 uses that cam with the revised LS7 roller lifters, 1.5 rocker arms, and a stout GMPP single roller timing set with Renold chain. Intake manifold is a Weiand 8121, carb is a 600 CFM Holley 80457SA. I also used GM intake manifold and valve cover gaskets. Not cheap!

Haven't fired it up yet, but I'm looking forward to lots of torque from 1500-4500 RPM, with peak horsepower at around 5000 RPM. That torque should help pull my truck's 2.73 axle.

 

[MadOgre]

I was wondering that also...

73 C10... does your current motor run? If so, good? You just want more power?

After looking at the specs on your motor, some better heads and a cam that you actually know a little about would move you forward very nicely. I would do a compression check and leak down test to begin with. If those pass, throw some better heads and a nice cam at it. Maybe an intake manifold too, I don't know what a Contender is. Dual or single plain? Heads, cam, and an intake will easily be way under your $2500 budget.

edit: Hell, maybe even just a new cam would be sufficient too. Biggest thing is figuring out your current cam specs. Know anybody an indicator that can reach down into the lifter bores to measure the actual lift on it? A degree wheel with an indicator can give you the duration of the cam also.

Exactly! If his motor is still in good shape probably just a RV cam will do the trick. Buy the full kit for $400 Cam, Springs, Lifters, Pushrods, Timing chain and gears.

If that doesn't do the trick you could spend on some DART SS Iron Eagle heads. Don't buy the fully assembled heads though.

 

[Skweegle89]

I think your going to spend too much unnecessary money if your motor is good. You like to fish? Those 1406 carbs make great trout line anchors. Ditch that and put a good qjet on it, performer intake and a decent RV cam and a set of headers and you will get the same power for a fraction of the cost.


Sent from an old rotary telephone.

 

[350runner]

spoken from experience^^^

Sent from the dust in front of you!

 

[73 C10]

Did your motor crater ?

No. I'm just sick of it running like crap. And it's weak. I would guess it's under 200hp. I doubt it will spin the tires now that I put posi in it. That's good and bad.

A couple of you guys stuck with me through this (it should explain why I don't like my engine):

http://www.gmsquarebody.com/forum/showthread.php?t=11085

But I never got the issue to go away. I thought Rich had me going in a good direction, but after a while, I think I was just masking the problem. I ended up smelling rich, and I had the timing as advanced as I could get it without pinging and it wouldn't start well. I tried everything that was suggested I think, and I'm grateful for the help. It just didn't solve anything, so I set everything back to stock and gave up on fixing anything.

I thought in the end, maybe I had a soft exhaust spring, or a bad lobe on the cam. But just guesses. But if I bought vortec heads, a cam, intake, and carb, I would be spending a lot of money and maybe not even fix the problem or be better off spending the money on something with greater potential. I would like to buy one thing that make it run smooth and be done.

When I ask about changing a few things, guys say just upgrade with a crate. Not here, but on the street. Now that I'm asking about a crate, guys are saying just fix what I have. And I will, but I don't have much money to be just throwing parts at it. I know an intelligent person would test and measure to diagnose properly, but I'm dumb and poor. I can't afford to pay someone to recheck everything I already did.

I'm just frustrated because I like working on stuff but not when I'm getting no where.

If you guys stick with me and can put up with my occasional somewhat dumb reactions, I'd like to get my current motor pumped up. I just don't know where the point of diminishing returns is. Like the 2 bolt main.

 

[73 C10]

I was wondering that also...

73 C10... does your current motor run? If so, good? You just want more power?

After looking at the specs on your motor, some better heads and a cam that you actually know a little about would move you forward very nicely. I would do a compression check and leak down test to begin with. If those pass, throw some better heads and a nice cam at it. Maybe an intake manifold too, I don't know what a Contender is. Dual or single plain? Heads, cam, and an intake will easily be way under your $2500 budget.

edit: Hell, maybe even just a new cam would be sufficient too. Biggest thing is figuring out your current cam specs. Know anybody an indicator that can reach down into the lifter bores to measure the actual lift on it? A degree wheel with an indicator can give you the duration of the cam also.

The Contender is a Holly. Dual plane.

 

[Old77]

Man....I feel like we've been all over the place with this as we discuss what the best option here is. It's hard to keep straight Let me try to do a very brief recap to maybe help make the decision so that you can at least get a direction to go towards and some goals set. You've already stated that an LS swap is not what you want so we'll throw that away. I think you've probably made a good decision based on your situation.

here we go...

1. @Green79Scottsdale made a good suggestion in this quote here...Would require some troubleshooting but has the potential of being the most cost effective and get you where you want to go with the fewest dollars spent.

I was wondering that also...

73 C10... does your current motor run? If so, good? You just want more power?

After looking at the specs on your motor, some better heads and a cam that you actually know a little about would move you forward very nicely. I would do a compression check and leak down test to begin with. If those pass, throw some better heads and a nice cam at it. Maybe an intake manifold too, I don't know what a Contender is. Dual or single plain? Heads, cam, and an intake will easily be way under your $2500 budget.

edit: Hell, maybe even just a new cam would be sufficient too. Biggest thing is figuring out your current cam specs. Know anybody an indicator that can reach down into the lifter bores to measure the actual lift on it? A degree wheel with an indicator can give you the duration of the cam also.

2. Long block crate motor and transfer some of the necessary items from your motor over to the long block. Possible warranty here but I don't think we ever confirmed for 100%

3. Full bolt in crate motor. Most come with a 3 yr/36k mile warranty. This swap should be able to be accomplished within a weekend

4. Grab a 350 of CL and rebuild it and swap it in. This would give less down time over rebuilding the 350 that's currently in your truck.


There were probably some other options with subtle variations of these but these are the more prominent one's that have been discussed I think. All have their pros and cons to them. It kinda depends on what you want. They all can be accomplished within your budget I believe.

 

[73 C10]

Man....I feel like we've been all over the place with this as we discuss what the best option here is. It's hard to keep straight Let me try to do a very brief recap to maybe help make the decision so that you can at least get a direction to go towards and some goals set. You've already stated that an LS swap is not what you want so we'll throw that away. I think you've probably made a good decision based on your situation.

here we go...

1. @Green79Scottsdale made a good suggestion in this quote here...Would require some troubleshooting but has the potential of being the most cost effective and get you where you want to go with the fewest dollars spent.


2. Long block crate motor and transfer some of the necessary items from your motor over to the long block. Possible warranty here but I don't think we ever confirmed for 100%

3. Full bolt in crate motor. Most come with a 3 yr/36k mile warranty. This swap should be able to be accomplished within a weekend

4. Grab a 350 of CL and rebuild it and swap it in. This would give less down time over rebuilding the 350 that's currently in your truck.


There were probably some other options with subtle variations of these but these are the more prominent one's that have been discussed I think. All have their pros and cons to them. It kinda depends on what you want. They all can be accomplished within your budget I believe.

#1 sounds OK except for the trouble shooting. The other post was troubleshooting and I still have trouble. I am willing to do it though.

#2 sounds like if done right, could ad some hp now and have potential for the future if the right block can be fired up for $2500.

#3 I don't know if can be done on budget. There always seams to be more to buy, like torque converter, flex plate, electric fuel pump, cam, etc.

#4 I've heard repeatedly that it cost the same to rebuild as to buy a crate and you just have a old motor with no warranty.

I am not arguing with you if you cant tell. I'm just confused and overloaded with good information.

 

[Old77]

I am not arguing with you if you cant tell. I'm just confused and overloaded with good information.

Yeah, I hear ya. Tis why I tried to consolidate into one post for you to hopefully help.

And about cost of rebuilding vs cost of crate. I know that when I was attacking drivetrain on my '77 (almost 10 years ago now ) I organized a spreadsheet and laid out exactly what it was going to cost to rebuild a 350 (would have had to buy a used one because mine came with a tired 305) it was going to cost almost exactly the same as a crate motor. This is why I opt for a crate back then and the LS motors that so many people swap now were virtually brand new back then so that wasn't an option.