Any drawbacks to using 1985 LA block to build 408 stroker?

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67cuda360

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Hi, I can scoop up a 1985 360 engine with 50,000KM for a few hundred dollars. In the future I was planning to do a 408 stroker build. Any drawbacks to using a 1985 LA block?

Originally I was planning to go the Magnum route since it already is setup for a roller, but maybe staying with a LA plant would be easier since I already have a LA block in the car.
I don't want to use the block I already have since the ears where the motor mounts attach are not great.

So any problems with a 1985 360 that I should know about?

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Hi, I can scoop up a 1985 360 engine with 50,000KM for a few hundred dollars. In the future I was planning to do a 408 stroker build. Any drawbacks to using a 1985 LA block?

Originally I was planning to go the Magnum route since it already is setup for a roller, but maybe staying with a LA plant would be easier since I already have a LA block in the car.


If you want roller, we built a 91 360 which is the last year of the LA heads, but has a roller cam...

I'm not sure what year they started the roller cams on the 318 and 360 in the late 80's, but someone else may be able to tell us what year the roller cams started in the 318/360...

92 was the first year of the magnum...

Once you know what years to look for a roller cam engine, you can use this search to find one near you... it's a national database of salvage yards across north america (Canada, USA, Mexico) and you can do a local search to find the ones near you, then sort them by mileage for a nice low wear block....

Car-Part.com--Used Auto Parts Market
 
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1st couple yrs of the magnum had oiling to the deck for shaft rockers still.
360's 74 and up all have the same potential for thick or thin cyl walls . Roll of the dice..
 
Just as with any block have it magnafluxed and sonic checked before putting any money into it.
 
Originally I was planning to go the Magnum route since it already is setup for a roller, but maybe staying with a LA plant would be easier since I already have a LA block in the car.
I don't want to use the block I already have since the ears where the motor mounts attach are not great.
I’ll assume that the current engines motor mounts are rotted, chipped or damaged in some way that gives you worry. Because the ‘85 LA 360 is the same configuration.

Otherwise, it should be fine for use. As said above, sonic check the block first and then order pistons with the kit. Just don’t assume the block can go .030 or .040 over bored. There really should be no problem.

FWIW, a good solid cam will work as well as a street roller cam. It’ll save you some bucks. If your heart is set on a roller, then go for it.
 
Yes I would have the block Sonic tested and Magnafluxed to make sure it is good to use. Staying with the LA block would allow me to use the same intake and other parts from my current engine (would save some money) vs going with a magnum. Also are things like aluminum heads more or less expensive for the Magnum?

I'm not sure what the number after 360 is on the side of the block, I guess I can check with the seller. What does the lower number mean?
 
Yes I would have the block Sonic tested and Magnafluxed to make sure it is good to use. Staying with the LA block would allow me to use the same intake and other parts from my current engine (would save some money) vs going with a magnum. Also are things like aluminum heads more or less expensive for the Magnum?

I'm not sure what the number after 360 is on the side of the block, I guess I can check with the seller. What does the lower number mean?
With a Magnum block, the lack of oil passages to the head creates problems. There are a couple of ways to get around it.

Use trick flow heads
Use LA heads with Comp Cams Pro Magnum rockers that allow pushrod oiling.
Create your own oil feed line. It was shown here on FABO & done externally with oil feed lines to the back of Edelbrock head that you need to drill. EZ job once you know how to do it.
Drill the block
 
FYI Roller cam LA's were cast in 1984 and went in 1985 cars for the 318. I believe the 360 roller blocks came a few years later. Photo of a 318 LA block
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hope not I used a 1985 360 for my 426 stroker , so far all is going well . don't see how you would have any problems . Good luck
 
Bick it up if the price is right
always good for a trade
and then grab a magnum block
 
I used an 86 truck block. Out of a camper special, hardly any miles.
 
Thanks for the replies everyone. I picked it up and it is sitting on the engine stand in the garage. Looks like it is a 87 block, looks very clean and has never been bored over etc. So I think It will make a nice candidate. When I get close to getting started on the build I will start a new thread to get some opinions and Ideas on what direction/parts to go with for a reliable street friendly pump gas 408 stroker.
Thanks again.
 
Thanks for the replies everyone. I picked it up and it is sitting on the engine stand in the garage. Looks like it is a 87 block, looks very clean and has never been bored over etc. So I think It will make a nice candidate. When I get close to getting started on the build I will start a new thread to get some opinions and Ideas on what direction/parts to go with for a reliable street friendly pump gas 408 stroker.
Thanks again.

Does it have the roller cam set up?
 
I haven't opened it up yet so I'm not sure, but I doubt it. When did the 360 first go to a roller setup? I thought it wasn't until 1990 and the magnum block
 
Darn LOL, even if I did want to go roller, I don't think the modifications are too drastic on the non-roller blocks.
 
I believe it has something to do with the revision of the casting mold.
Bingo!
I would still sonic check the cylinder walls if I was building a serious engine, regardless of the year or core numbers.
It's cheap insurance so you know absolutely what you have to work with..........
 
I'm also curious as to what the - number means after the 360.

The higher the number the more chance of porosity . Here is a X block race block 318-11 . This block took a lot of work to save it. If it wasn't a X block with 4 bolt mains it would have been trashed. The right rear lifter bore was mostly missing. If you look close at the pics you can see the burn from welding it back in with shartanium rods . The higher the number the more contaminants in the iron. Due to it being pored at the end of the ladle. The first pore is the best up to -6 they seam pretty good .

340-1's are highly sought after in the sprint car world. I have pictures of some 1's and higher numbers loaded side by side if I find them I'll post them. You can visually see the difference in the quality after cooked in an acid hot tank . Always try and find a low number. They usually sonic test true and less flashing.

From the hot tank to the rinse booth then the true casting is seen. Again if your putting some serious money in a motor for performance get a low number. The lower the better. 6 and under. I have 340-7's and up I get $250 for them. they are pressure tested standard bore we won't use them for a race motor. Good for a rebuild nothing with high horse power. Several here for pick up only.

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