# 400 sbc ?'s **URL:** \ **Category:** PittSpeed Automotive\ **Created:** [January 9, 2007, 2:43pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317 "2007-01-09T14:43:47Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![neonracer01](https://avatars.discourse-cdn.com/v4/letter/n/9fc348/32.png) [@neonracer01](https://forums.speedlife.net/u/neonracer01)\ **Post date:** [January 9, 2007, 2:43pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/1 "2007-01-09T14:43:47Z")
looking for some 400 info and maybe general chevy answers. 1 is the 400 a 6.6 liter? 2 ive read they had cooling issues. what are they? 3 what did chevy call the engine ( for example ls1/lt1) if anything at all. 4 i read if you put a 350 crank in a 400 block it will be destroked to a 377 . do you still use all of the other stock 400 parts and just bolt the 350 crank to the 400 rods and pistons and cam and run it? or do you have to change more than just the crank? that should do it for now. ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [January 9, 2007, 2:59pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/2 "2007-01-09T14:59:04Z")
Can answer #2…the steam holes that are between the cylinders were troublesome and some had overheating problems. #4… must use 350 crank with main bearing spacers, 350 [5.7] rods with special order pistons…however I know that keith black 377 pistons are the same # as 400’s…top end of your choice. In the “old days” we threw many 400’s away because we considered them junk…however we didn’t have the choice of aftermarket parts we have today. ---
**Author:** ![Pewter](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/pewter/32/5936_2.png) [@Pewter](https://forums.speedlife.net/u/Pewter)\ **Post date:** [January 9, 2007, 3:01pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/3 "2007-01-09T15:01:14Z")
> [@FS: 1990 BMW 325is](https://forums.speedlife.net/t/fs-1990-bmw-325is/24960/35): > > looking for some 400 info and maybe general chevy answers. > > 1 is the 400 a 6.6 liter? > 2 ive read they had cooling issues. what are they? > 3 what did chevy call the engine ( for example ls1/lt1) if anything at all. > 4 i read if you put a 350 crank in a 400 block it will be destroked to a 377 . do you still use all of the other stock 400 parts and just bolt the 350 crank to the 400 rods and pistons and cam and run it? or do you have to change more than just the crank? > > that should do it for now. 1 yes 2thin cyl walls will over heat to much in a 3rd gen f-body! 3 gen1 small block 4 yes ,it we be a 383,cam what ever u choose ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [January 9, 2007, 3:07pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/4 "2007-01-09T15:07:13Z")
Pewter, check #4 ---
**Author:** ![bgblockelcamino](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bgblockelcamino/32/5997_2.png) [@bgblockelcamino](https://forums.speedlife.net/u/bgblockelcamino)\ **Post date:** [January 9, 2007, 3:36pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/5 "2007-01-09T15:36:54Z")
350 crank makes 377 if i remember correctly the earlier ones had 2 freeze plugs. which are the ones to search for. most times they are easily identified with 3 freeze plugs per side of block. with thin cylinder walls makes them prone to run hot. what are your plans with 400 SBC? ---
**Author:** ![eurodad](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/eurodad/32/5988_2.png) [@eurodad](https://forums.speedlife.net/u/eurodad)\ **Post date:** [January 9, 2007, 3:49pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/6 "2007-01-09T15:49:59Z")
i’ve heard all the overheating stories, but have yet to actually see or meet someone who actually had it happen, also heard it is not really a problem until you start boring more than 30 over the 350 crank in a 400 block shifts the power upward in the powerband alittle. and i’m 99.9% sure both the 350 with a 400 crank, and a 400 with a 350 crank using stock bores are both 377’s. 30 over bore makes 383’s. i have no idea about the which pistons or rods to use. but my guess would be 350 rods and 400 pistons ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [January 9, 2007, 4:13pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/7 "2007-01-09T16:13:46Z")
Stock 400 block with 350 crank is a 372. 30 over gives you a 377. A 400 in a heavy pickup or towing would always run on the hot side…Just the nature of the beast ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [January 9, 2007, 5:00pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/8 "2007-01-09T17:00:51Z")
> [@Incredible NSX vs R33 GTR video](https://forums.speedlife.net/t/incredible-nsx-vs-r33-gtr-video/27109/24): > > Stock 400 block with 350 crank is a 372. 30 over gives you a 377. > > A 400 in a heavy pickup or towing would always run on the hot side…Just the nature of the beast Wasn’t this where GM dumped most of the 400’s? ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [January 9, 2007, 5:18pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/9 "2007-01-09T17:18:42Z")
correct…you would find a few in implalas and caprices ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [January 9, 2007, 5:26pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/10 "2007-01-09T17:26:52Z")
> [@STUFFED UP NOSE!!!!!!](https://forums.speedlife.net/t/stuffed-up-nose/27157/34): > > correct…you would find a few in implalas and caprices Thats what I was thinking but wasn’t sure. ---
**Author:** ![Pewter](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/pewter/32/5936_2.png) [@Pewter](https://forums.speedlife.net/u/Pewter)\ **Post date:** [January 9, 2007, 5:34pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/11 "2007-01-09T17:34:22Z")
> [@FS: VG30DETT](https://forums.speedlife.net/t/fs-vg30dett/26680/25): > > Pewter, check #4 its been a long time ,brain fart:hsugh: ---
**Author:** ![Orr89rocz](https://avatars.discourse-cdn.com/v4/letter/o/ac91a4/32.png) [@Orr89rocz](https://forums.speedlife.net/u/Orr89rocz)\ **Post date:** [January 9, 2007, 6:46pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/12 "2007-01-09T18:46:36Z")
low temp thermostat, a good radiator, and good electric dual fans will keep it cool. i havent heard of many overheating problems if those are taken care of. aftermarket heads need steam holes drilled into them to run on 400sbc ---
**Author:** ![Pewter](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/pewter/32/5936_2.png) [@Pewter](https://forums.speedlife.net/u/Pewter)\ **Post date:** [January 9, 2007, 7:27pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/13 "2007-01-09T19:27:44Z")
> [@fs: integra rear disk swap](https://forums.speedlife.net/t/fs-integra-rear-disk-swap/27031/4): > > low temp thermostat, a good radiator, and good electric dual fans will keep it cool. > > i havent heard of many overheating problems if those are taken care of. aftermarket heads need steam holes drilled into them to run on 400sbc haha youngin! ---
**Author:** ![eurodad](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/eurodad/32/5988_2.png) [@eurodad](https://forums.speedlife.net/u/eurodad)\ **Post date:** [January 10, 2007, 5:45am UTC](https://forums.speedlife.net/t/400-sbc-s/187317/14 "2007-01-10T05:45:40Z")
just do a 406. find a good 400 crank or get the current one cut, bore it 30 over and run it. get a set of ls1 fans from brian. and i think you should be running the lower spoiler piece too brian should know what i mean. ---
**Author:** ![neonracer01](https://avatars.discourse-cdn.com/v4/letter/n/9fc348/32.png) [@neonracer01](https://forums.speedlife.net/u/neonracer01)\ **Post date:** [January 10, 2007, 1:18pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/15 "2007-01-10T13:18:05Z")
i got the kit to rebuild the 400 already and i have the spoiler piece too . i just need a few more things and its going in. the other 400 block we got off you is running already and in a 98 s-10. ---
**Author:** ![German\_with\_a\_Bowtie](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/german_with_a_bowtie/32/5967_2.png) [@German\_with\_a\_Bowtie](https://forums.speedlife.net/u/German_with_a_Bowtie)\ **Post date:** [January 10, 2007, 1:53pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/16 "2007-01-10T13:53:57Z")
My vote, **406** all the way! A half fill of block hardner, longer con rods, good heads and a big cam NICE! Best 400 block casting number ends with 509…Hi Nickle block A buddy of mine ran one in his Chevelle destroked to 377, ran GREAT! GM off road mechanical cam, worked camel backs. What a ride! I remember there being issues with the thick bearings…always use the spacers and 350 bearings if you’re gonna do this. ---
**Author:** ![eurodad](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/eurodad/32/5988_2.png) [@eurodad](https://forums.speedlife.net/u/eurodad)\ **Post date:** [January 10, 2007, 1:58pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/17 "2007-01-10T13:58:44Z")
> [@5/20 Nyspeed BBQ @ Chestnut Ridge \*\*PAYMENT INFO INSIDE\*\*](https://forums.speedlife.net/t/5-20-nyspeed-bbq-chestnut-ridge-payment-info-inside/24869/84): > > i got the kit to rebuild the 400 already and i have the spoiler piece too . i just need a few more things and its going in. the other 400 block we got off you is running already and in a 98 s-10. runs good? what cam and heads did he use and did he overbore it? ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [January 10, 2007, 3:04pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/18 "2007-01-10T15:04:40Z")
I’ll second half fill the block! ---
**Author:** ![Orr89rocz](https://avatars.discourse-cdn.com/v4/letter/o/ac91a4/32.png) [@Orr89rocz](https://forums.speedlife.net/u/Orr89rocz)\ **Post date:** [January 10, 2007, 3:05pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/19 "2007-01-10T15:05:06Z")
Destroked 377’s make damn good motors. they can rev quickly with that short stroke, and make good power with big bore. can take advantage of more airflow from bigger heads. but if i had a 400 block, i’d bore it out some and make it a 412-415. thats my dream motor…a Motown 415 with a small turbo on it or a procharger. ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [January 10, 2007, 3:09pm UTC](https://forums.speedlife.net/t/400-sbc-s/187317/20 "2007-01-10T15:09:08Z")
> [@First Ipod Virus Found?](https://forums.speedlife.net/t/first-ipod-virus-found/27191/2): > > runs good? what cam and heads did he use and did he overbore it? 30 over, running 202 heads with 3 angle valve job, cant rebember the cam specs, decent idle, edelbrock intake and carb, msd ignition, turbo 350 (now blown). Turned out to be a pretty strong runner… [Next page](https://forums.speedlife.net/t/400-sbc-s/187317.md?page=2)