does a 383 run a lot hotter than a 350?

[H-K]

I'd heard previously that a 383 runs unusually hot and is not well-suited for a crawler with limited airflow. I have googled the hell out of the net to try and find some info to (1) verify this claim and (2) see if there are any remedies. I have found squat that speaks to the 383 having any disproportionate cooling issues compared to the 350. What I did find is that the 400 blocks have cooling issues because of the lack of water jackets between the mid cylinders. I also found threads where people were debating between a 400 or 383 and usually the consensus was to opt for the 383 because it runs cooler.



So, I'm wondering if anybody on RME has had any experience with this or any knowledge that would help me (and maybe others) out.

Thanks for any help.

JP

 

[red]

not on the rocks but one of my friends back in Texas has a 383 in his reg cab step side 82 chevy and he has no cooling issues playin around in the woods and out in the mud.

 

[mbryson]

... What I did find is that the 400 blocks have cooling issues ......

"cooling issues" = 5* or so?

A 400 will run a little hotter than 'normal' small blocks, but not significant. Let the wimps give me all their 400s. I'll take them.

 

[420willys]

now dont hold this to me, but i think what your refering to is when you take a 350 and boar it out to make a 383, not like a true stroker 383. there's a very thing water jacket when you boar the motor out, so agin dont quote me on this but this is what i think the cooling issue with a 383 is ( non stroker ), jason.

 

[soda blaster]

it really depends on if like stated above if you just bore it out or if you stroke or destroke it I personally like a destroked 400 but that is my opinoin I am sure others on here will voice their dislike of this. just run an aluminum radiator and a good electric fan and you will not have any problems.

 

[kowe69]

I am running a Vortec 350 that I bored and stroked to 383 in my truck. Only .030" is bored out of the cylinders. Hardly enough to cause cooling problems. The rest of the displacement is obtained by installing a 400 crank into the 350 to get a longer stroke. I have had no cooling problems what's so ever. This engine runs as normally as a stock engine. I did install a 160 degree thermostat mainly to reduce spark knock due to the 10.5 to 1 compression, not because of heat related issues. There is another stroker motor where a 400 block is used with a 350 crank. this comes out to like 377 CID or something. This setup is mostly used for top end horsepower applications like drag racing. That is the only stroker motor that I know of that may have heat concerns due to the siamese cylinder walls. But this is rarely actually a problem.

 

[mbryson]

I am running a Vortec 350 that I bored and stroked to 383 in my truck. Only .030" is bored out of the cylinders. Hardly enough to cause cooling problems. The rest of the displacement is obtained by installing a 400 crank into the 350 to get a longer stroke. I have had no cooling problems what's so ever. This engine runs as normally as a stock engine. I did install a 160 degree thermostat mainly to reduce spark knock due to the 10.5 to 1 compression, not because of heat related issues. There is another stroker motor where a 400 block is used with a 350 crank. this comes out to like 377 CID or something. This setup is mostly used for top end horsepower applications like drag racing. That is the only stroker motor that I know of that may have heat concerns due to the siamese cylinder walls. But this is rarely actually a problem.

He's dead right about the 377 vs. the 383. I don't remember all the combos and the exact over bores, but the 383, 388 are 350 based engines with 400 blocks. 377s are 400 engines with a 350 crank. They rap up like a Honda motor and make some CRAZY horsepower with a single plane intake and some nice flowing heads.

He's also dead right about the siamesed cylinder walls being a 'non-issue' if your cooling system is up to task. If your 400 is running hot, you've got something wrong. Either with the steam holes in the heads or your water pump, fan, radiator or thermostat (or any combination of those).

I LOVE 400 small blocks. (but I'd just go with the 406 vs. the 383--the extra cubes are worth it--when you're really cool and want to spend some money, you can get a 400 SB to about 440 cubes---they're SWEET )

 

[BumpaD_Z28]

I agree with the above my Vortec 388 (4.060 bore x 3.75 stroke) runs at 165 ... mid August at an idle, in deadlock traffic .... no heat issues AT ALL

~DaVe

 

[H-K]

Thanks for the replies and info. Sounds like the concerns are unfounded, and looks like I'll be stroking a 350 to get a couple of extra ponies out of this turd '91 350.