Hi, What all has to be done to a 350 block to make it ready for it to accept a 383 stroker (400)crank??? I have heard that the block has to be Notched... then someone told me that if you just use 400 rods instead of the 383 rods, you don't have to.... can someone straighten me out on this??? can I get a 383 made without notching the block for clearance??? is there plenty of clearence allready???I have heard so many stories, I can't figure it out myself...lol...

Please help!!!
Thanks!!!

A buddy of mine built a 383 recently and he had to notch the block. Don't be afraid to do it, it's pretty easy. Place the crank in the block with two rods and pistons (without rings) on the same journal and tighten the bolts just a little. Use used bearings that are not too worn, or new ones and lots of oil to not damage the crank. Do one journal at a time, and clean after each notch...

Yes, you will have to clearance the block for the new crank. You will also have to gring some off the rod bolt and maybe use a small base circle cam as well. At least that's what a friend of mine had to do. Incedently, he tells me it was worth it.

If you're really afraid to do the notching and you don't already have a block, you could buy the block that GMPP is using for the HT383. I don't know the part number off the top of my head, but it shouldn't be too hard to find. It is a different part number than the one for the ZZ4 350 block since it's already notched from the factory. Might be worth checking in to. The cost is around five or six hundred bucks. Note that this block has a standard 4" bore so if you really wanted a 383 using a 3.75" stroke, you'd need to bore it 0.030 over.

Sounds like the notching think isn't too much of a deal, just need to make sure you have enough clearance.

yes, you can run 400 rods (5.565") and not have to clearance the block. I have 400 rods in my 383.

im building a 388 (.60 over 383) right now with 400 rods and i dont have to clearance any thing, and i got the opinion of the local engine builder to back that up.
~RoB

im building a 388 (.60 over 383) right now with 400 rods and i dont have to clearance any thing, and i got the opinion of the local engine builder to back that up.
~RoB

to put in a 383 stroker crank, and use 400 rods, what all has to be done to the block??? I know it has to be bored .030 over... but does it have to be align bored??? or honed??? for the crank.... and what type of pistons do I use??? 350 (.030 over)? or 400 pistons???

Thanks!!!

Blocks are slightly different. The amount needed to be removed is pretty small, some blocks need more clearancing than others. The bolt on the 400 rod is shorter, but it is shorter on top for cam clearance. The bottom SHOULD be the same dimentions as a 5.7 rod.

The 1st 383 that I built, 1987, I used 400 rods. two of the rod bolt nuts hit the block, needed clearancing in 3 spots. My current 383 with 5.7 rods only hit in one spot.

so, what should I do??? I am basically looking for the quickest,easyest, and (Most importantly) cheapest way to build a 383 stroker... I don't really want to go cutting on the block... also, what would I use to cut that, or would I have to get a machine shop to do it??? and still the question stands... what type of rods??? I was thinking if I could just use 400 rods with a 383 stroker crank, that it would just drop right in...
Is there anyway to make it do that???

Oops! Sorry. I didn't consider the 400 rods in my post. My buddy used a 6" rod.

There are some rods that don't require block notching on a 383< 400 crank,350 rods@3.75">. Also most recomend a small base circle cam too due to clearance issues. If you use the 400 rods<shorter@3.57"> I think that gives you a 377<destroked>.The GMPP 383 uses a standard bore 350 block and longer<3.82?< rods are powdered metal> to get to 383ci.

I think thats the correct rod lenths?

I thought a 377 was a 400 block with a 350 crank, not sure which rods, 400's I think.

yes, 377 is (among other variations) a 400 with a 350 stroke (3.48) rod length has no effect on cubic inches. no personal experience with 377 or 383's, but have heard you can run the shorter 400 rod without clearancing the block in a 383. i beam rods allow more room than h beams, for sure. but really, if you are tackling a 383 build, block clearancing isn't really a big deal. i would actually not trust the 400 rod theory myself, it seems to me the longer (3.75) crank stroke in the 350 block will be the largest factor, though i would imagine the shorter rods would clear up any cam interference issues. again, no experience with 383 or 377's, but i would by all means mock up and check any other than factory configuration, period. remember, any time you deviate from factory, there will surely need to be some engineering on the fly, if you will. good luck, and now is a good time to learn how! graemlins/thumbsup.gif

Originally posted by Prostreetcamaro1:
so, what should I do??? I am basically looking for the quickest,easyest, and (Most importantly) cheapest way to build a 383 stroker... I don't really want to go cutting on the block... also, what would I use to cut that, or would I have to get a machine shop to do it??? and still the question stands... what type of rods??? I was thinking if I could just use 400 rods with a 383 stroker crank, that it would just drop right in...
Is there anyway to make it do that??? I've never heard of anyone having to clearance their block using 400 rods. Go out and buy some good arp rod bolts (I'm running ARP Wave-loc), take your rotating assembly to a shop and have them balance it. You shouldnt need any clearancing and yes a machine shop can do that for a few bucks ($40 - $50 if that much). And yes, it will drop right in if you're using a "383" crank, meaning, the mains have been ground down to 350 mains..if so you're ready to rock and roll! (JUST DONT FORGET TO BALANCE IT!)

hey there man I got a 383 stroker and the best thing that you can do to have it right is take it to the machine shop. have them clean the journals for the crank to accept that 400 crank, was around 300 to have my block done but it was done right the first time, with a garentee that it would work.

Mind if I put 2cents here,,, Using the 350 block and going for the 383 and using the Scat kit,,,their rods , etc,,, Do you still have to notch? Can you still use the full base circle cam? And last would using 6" rods throw in extra clearance problems???

383 400 crank mains ground to 350 ,rods the same 400 rod with 30 over 350 piston no clearenceing. i do recomend using good rod bolts no matter what rod you use 350 rods you will more than likely have to clearance the block some and clearance the rod bolts for the cam shaft unless you use a small base circle cam

If you don't want to build your own look at a short block from somewhere like Speed O Motive. Thats where I got mine for about $1,600 then start bolting everything on to the short block.