I want this thread to show the REAL pros and cons of each, here is what I THINK I know

I want the answers for a street driven pumpgas max effort peice.

383 has a better rod ratio and is easier on the thrust side, especially with a 6 inch rod, the 5.7 rod has less tdc time and should have a stronger "pull" on the intake charge, the 6 inch should lack in this area. But the 6 inch rod 383 should last longer and be easier on the piston wall


The 396 is 13 inches bigger, should make more torque with the bigger arm, the rod ratio is worse, harder side loading on the piston, the pin is in the oil ring, in theory would be much harder on parts street driving, compressio height on the piston is very short(depending on rod length)


And BTW before I get drilled about feeding either on of these combo's"correctly" I will put the heads needed to do it right.

I was told by Airflow development that getting a 3600lb Z28 in the tens with a 23* head normally aspirated was flat out impossible, cant be done with a 383 or a 396.

I was also told a 3600 lb Z with an auto making 500 rwhp COULD NOT run 10.90's, but there is a 3700 lb Z in town making 505 to the tire that goes quicker than 10.90


SO which would you build? safe long living 383, or ***** out on fire dont care 396?


Discuss.



David

 

4" stroke w/ big heads

 

***** to the wall 396

 

Ok let me throw this in, If you had access to a screaming deal on a factory 4bolt 383, all eagle forged rotating assembly, with a flywheel, 95 up timing cover and opti and harness, comp cams 306(which I wont use) Double roller timing chain for $2200 what would you do...shortblock has around 600 miles on it and you know the guy and his Dad who built it? WHat would you do tthen?



David

 

Buy it. If you won't give me his name and contact info and I will.

 

It'll make more torque because of the added displacement. The longer arm has nothing to do with it. Contrary to what we always thought until a couple years ago.

 

By bigger arm I mean stroke of the crank, not the rod.


I think I will go ahead with the 383 here locally and just live with what it produces.


David

 

With the money you will save in heads and other various parts, as well as the shortblock, you should be able to get yourself a nice nitrous setup to make up for the power you lose.

 

383 is the smart setup, IMHO.

Rich

 

Airflowwhoever possibly doesn't know a whole lot.

If you think there is a big difference between the two, do a search, it's been discussed.

Build whatever you want and then worry about the topend parts that actually make the power. You can go 10's with a stock shortblock N/A at that weight. It's been done and it wasn't on a top fuel budget.

 

i went with the 396 but that was 5 years ago when i built it. if i could start with all the money i had and start a new motor it would be a forged 355 with either 18* heads and carbed and a solid roller or the 32 valve dominion heads with a bret bauer intake and solid roller

 

Alright guys another question, it will be a solid roller, Probably Pro-action heads converted and a super vic, monoblade and an elbow from intake elbows.com, 42 lb injectors, zero deck flat top with a 8cc relief. Prolly 12 to 1 on pumpgas,upper 8's on dynamic compression. Stock ecm and opti, 1 7/8 headers, 3.5 inch Y pipe, 4 inch mufflex.

Will Morel Lifters live on the street? Not a daily driver but a weekend cruiser that will see strip duty. Prolly 4 to 5 k a year, I plan on buying what is needed, toolroom springs, titanuim locks-retainers, Shaft rockers etc, all the best..and if they will do I need restrictors up top?

Do you guys see any holes in my plan?


Thanks
David

 

WOW, Did I get mis-quoted or what!

 

That's a shame. I hate being mis-quoted.

 

I know Dennis and if he says your barking up the wrong tree, you probably are. I know he can get a 3600lbs car to go 10's with 23° heads, but your combination is much, much harder to get that out of. Drag Radials, Lots of Weight, 4L60 Tranny, etc... I'm still weary about the whole combination, would it be something interesting to try, yes, do I think it's going to be easy, no.

Either way I wouldn't drag his name thru the mud on a billion websites, because you don't agree with him, he's been there done that many, many times.

Bret