383 or 408
383 or 408 aluminum 383 or iron 408?? Is the extra cubes worth the weight?? Ill be spraying a 150 shot every now and again. Im going with the eagle stroker kit that HPE sells both are the same price.
If you can overcome the extra 100 pounds then it won't be much of a comparison. Do a few weight savings tricks and you should make up the weight pretty easy. Then again, the numbers put out by both are pretty similar. You just don't see alot of 383's. Personally, I'd stay with the aluminum, but lots swap for the iron now days. Either would be a good choice. You'll always be slower than me, so you might as well be pissin in the wind.
I had this same decision. I chose iron of course. My rationale was it takes approx 20 to 25rwhp to move 80 to 100lbs off the line. I looked at the 96 F-body weights and compared them to the LS1's and the weight difference was around 85lbs. The LT1's got around just fine with the extra 85lbs. A 408ci will make more horsepower/torque than a 383ci. Plus, it only takes minor weight reduction to lose 85lbs. Of course the losing of 85lbs depends on your starting point.
Now that we have the LS2, you might want to think of that route. You will start out with a 6.0L block and all you will need is a bigger crank to get the cubes you want. With a 4.00 bore x 4.00 stroke you will have a 402ci.. You get the best of both worlds. Unfortunately the LS2 was not an option when I was making my decision. You have the option..
Now that we have the LS2, you might want to think of that route. You will start out with a 6.0L block and all you will need is a bigger crank to get the cubes you want. With a 4.00 bore x 4.00 stroke you will have a 402ci.. You get the best of both worlds. Unfortunately the LS2 was not an option when I was making my decision. You have the option..
Weight saving I already have once I make the decision. I have a BMR K member and lower control arms. Will also go with a light weight battery. Any guess on how much more hp and tq were talking about with the 408??
Jason might be faster if you ever get around to installing your parts
Jason might be faster if you ever get around to installing your parts
Originally Posted by FigsZ28
Weight saving I already have once I make the decision. I have a BMR K member and lower control arms. Will also go with a light weight battery. Any guess on how much more hp and tq were talking about with the 408??
Jason might be faster if you ever get around to installing your parts
Jason might be faster if you ever get around to installing your parts
Also, your dyno #'s will depend on how radical you are willing to go. You would have to go more radical to get the 383ci to dyno as high as a 408ci with similar mods. Therefore sacrificing driveability. Now these are all just my opinion. I have been in two iron block cars. My old 95 TA and 383LQ4SS's car. I did not know my 95 TA had a iron block until I started modding it and I was told. In 383LQ4SS's car you cant tell at all. It drives just like it had an alum in the car and this was b4 Al did any weight reduction.
Originally Posted by FigsZ28
Jason might be faster if you ever get around to installing your parts
But really, I'm still waiting on a few things and I'll be ready to go. There is really only one way to look at the situation you are in: Dyno numbers vary so much that it is hard to get a good answer. There are so few 383's and 408's running that it is hard to get solid numbers. The way I look at it is, if done properly, more cubic inches will equal more power across the board. You've done the weight reduction, so the only downfall will be adding back a few extra pounds. You could always buy a C5-R block! 
TECH Junkie
Joined: Dec 2001
Posts: 3,242
Likes: 0
From: Lakeland, FL
The deciding factor for me was that my heads ended up being fubared. Since I needed new heads the IRON would have been the same price as the 383. I figured the iron would be stronger and be able to rev higher than the stroker 383 so I decided 408.
Trending Topics
Why not go 406 in the aluminum (4.250 stroke) . Does it get too tricky when stroking that much? I know additional clearance may be necessary but are the blocks unreliable at that point?
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
I would stay with aluminum. That is a pretty big weight difference hanging off the front of the car. I personally have never heard of an alu LS1 block blowing up simple because it is made out of aluminum.
The 6.0 truck block weigh's 72 lbs more than the ls1 block, if you had them both torn down bare. Relocating the battery would almost be enough to rebalance the car. The only real deciding factor is how much $$ do you want to spend? I think that the only place that I have heard of the aluminum block being an issue was with extremely high amounts of boost. I remember hearing about someone lifting heads off the block, and the problem ended up being the head studs actually pulled up out of the threads in the block. That's the only failure I recall, other than the guys with resleeving issues, but that's a whole different issue. LS2 would be worth looking at too, unless you are doing this project immediately.
Originally Posted by ROCNDAV
Why not go 406 in the aluminum (4.250 stroke) . Does it get too tricky when stroking that much? I know additional clearance may be necessary but are the blocks unreliable at that point?
FormerVendor
Joined: Nov 2001
Posts: 3,065
Likes: 6
From: Houston, Tx.
The 4.250 sroke is doable but probably not as strong with the pistons you need to run to keep everything in the bore when pulling it down that far. The C5R could maybe use it but the normal LSx blocks cylinders just aren't that long. Then there's the fact as Beast said that only big dollar cranks are being made at that stroke. I've used Eagle in 1000hp drag engines and never had a problem. The Cola would be fine too but most of their regular SBC stuff is anchor heavy. Haven't seen their LSx stuff yet.
Check out http://www.scatcrankshafts.com/ they will make any crank for you (Speak with Peter Leid, tell him David McAfee sent you). He told me there is no price difference in the crank stroke but as Beast said machine work and pistons will cost more.
D
D
Im leaning more towards the 408, im hoping to get around 500rwhp with the mods in my sig. I was also thinking of getting the cam APE put in there 408 to accomplish the 500 rwhp. Plus I think the lightweight suspension mods i do will help with the weight offset.
On The Tree
Joined: Jan 2004
Posts: 151
Likes: 0
From: albany, new york
Originally Posted by FigsZ28
Im leaning more towards the 408, im hoping to get around 500rwhp with the mods in my sig. I was also thinking of getting the cam APE put in there 408 to accomplish the 500 rwhp. Plus I think the lightweight suspension mods i do will help with the weight offset.
Originally Posted by 383ss
just for reference, my 383 put down 485/475 with the 78mm LSX, now has the 90 and should be around 500 rwhp. with a 'small' 236/232 .600 cam.
11Bravo, I was going to reply exactly the same I'm no LS1 expert, and forgive me for ever saying this, but what about all of those little ricers suping up their motors. Most of those motors are all aluminum too, arent they? It's trippy to hear my neighbor's kid tell me what some of his friends are doing to their motors (boost, nitrous)
D
I'm no LS1 expert, and forgive me for ever saying this, but what about all of those little ricers suping up their motors. Most of those motors are all aluminum too, arent they? It's trippy to hear my neighbor's kid tell me what some of his friends are doing to their motors (boost, nitrous)D