I need help. I have a project car I bought half started. The guy had a 400 chevy small block which I just took out and sold last week. now I'm shopping for a 383 stroker turn key crate engine. I noticed that they have 1 piece real seal and 2 piece rear seals. Does either one fit my transmission? or do they have different bolt patterns? I think I have a 700r4 trans. Thats what the guy told me but I havent confirmed yet.

 

All the same block bolt pattern. Difference is you'll need a different flexplate for the 1 pc vs 2 pc seal and then from there determine if you want to stay with 153 or 168 tooth

 

Why did you sell the 400, just to turn around and buy less of an engine?/

All gen 1 small blocks (and big blocks) 1955 up uses the same transmission bolt pattern.

The diff in 1 pc vs 2 pc rear main seal will be in the oil pan, flywheel/flexplate, crankshaft.

 

The one piece is intended to seal more effectively over time than the two piece, assuming the seal is installed correctly. The two piece has a larger bolt circle at the flywheel attachment which may provide more torque capacity. I don't know if that matters below 700HP. I do like the fact that the two piece 350 is truly zero balance. It doesn't depend on a counter weighted flexplate/flywheel like the one piece does.

 

I couldn't get it running right. I'm not an engine guy. I'm more of a body modification guy. I got fed up with it and sold it for 2k. I want is to put a turnkey engine in it and start working on the body. Hopefully I can do that without any major issues. Thank you all for the information...

 

[quote=Night rider327;5839096]Why did you sell the 400, just to turn around and buy less of an engine?/

And this from the guy who runs low 10s with a 327.

 

If you ever want to run a five or six speed transmission without paying hundreds for a conversion piece get a one piece. If you are sticking with an auto a two piece is fine and probably cheaper.

 

[QUOTE=ASE doc;5839148]Nope, and nope..No 327 here.
Read the little info tab under my user's screen name.
Or read info that I posted in threads.

10.34:1 355, brodix IK200 heads, solid flat tappet 249/252@.050" cam, th-400, 3500 stall, ford 9" 3.89 gears, detroit locker..

I have said many times I have never ran this combo at the track (life got in the way) but should be a 10.60's car..

My old combo went 11.40's @ 118 , 1.60's 60' and it was a 355 as well.

Don't assume my username means what engine I run lol.

The "night rider" name is from my CB radio days and that was my handle. Night rider was already used when I joined this site so I had to add something with it.. The 327 portion came from my 1st drag car I built when I was 15. It was a vega, with a 6-71 diesel blower converted to gas on a 327 engine with a M22 4 speed behind it.

 

2 piece rear main, the rear seal is on the end of the crankshaft inside the last bearing cap. You can change the seal by dropping the oil pan, removing the rear main cap with lower portion of the seal and rolling in the upper portion of the seal over the crankshaft.

With a 1 piece rear main seal, the seal is held on in a retainer at the back of the engine. To change the seal, the transmission needs to be removed.

Both designs work just fine and both designs have their own difficulties in replacing. The gen 1 SBC blocks use 2 piece rear mains. The newer engines use a 1 piece. Flexplate/flywheels for each style are not interchangeable because the end of the crankshafts are different.

 

Quote: 10.34:1 355, brodix IK200 heads, solid flat tappet 249/252@.050" cam, th-400, 3500 stall, ford 9" 3.89 gears, detroit locker..

I guess I knew that. Just forgot. Still, 355 running 10s is impressive. certainly proves that increased stroke isn't the only way to make power. Of course, I also remember something about 4-5" idle vacuum.

 

Thanks.. It has not been an easy road to 10 second timeslips with a 350.

lol yep, I guess that's the price you pay to play with smaller cid engines.
Yeah only 4-5" vac at 1000 rpm idle speed, and 7 mpg.

I love the shorter stroke engines just cause I cut my teeth on them, but truth be told I sure wish I had went with a 400 block and a 3.8750" or 4.000" stroke. Hitting 10's would have been so much easier and more streetable.

 

You and I come from the same place. I started out with small block Nascar engines. 500hp from 355 CID. That was just the small time local guys. The big boys have made closer to 800HP. Of course none of those motors run on any less than 108 octane and even then, they don't do so well under 3,000rpm. I had planned to put together a streetable version of the big bore short stroke 377 and try to push for 600+. My machinist thinks it's doable. But I finally had to recognize that more cubes, especially a little more stroke, makes more torque at lower revs. It's that torque that makes an engine streetable. Plus, when we consider HP per cubic inch, more cubes just allows us to make that much more power. I could make the high rev 377 work with the right stall speed and gearing, but I would probably always wonder if the 406 wouldn't have been a better choice.

That's why I've pretty much decided to go ahead with the 406. The cost of the build is pretty much the same. The only down side of building the 406 is that I have a good set of 65cc chamber heads. The small chambers will require the use of dished pistons with the longer stroke. Since creating an effective chamber with great quench and mixture management is the key to making power, using dish pistons will make things more complicated. I may just start with flat tops and have the crowns custom cut to match the twisted wedge chambers. Otherwise, I toss these heads for a set of 72cc and I really don't want to do that. I will have to talk this over with Archie(Somers Automotive Machine) and we'll figure out what to do.