SAM98WS6

30lbs arent really enough but they will do.

No comparison between a 346 and a stroker. Get a stroker.

Benjamin Russick

iTrader: (1)

Well, I don't really want to do a 347 because I figure that if I'm going to go forged, I might as well go all out. I already make 576/590 on a wet 100shot, but off the spray the engine is kind of soft below 3500 rpm. I want more punch/grunt that is usable throughout the RPM range. I figure with a 150shot on top of a 382/402/408, I could be well over 650rwhp and still daily-drivable in theory (the car is a garage-queen).

beardWS6

iTrader: (1)

No replacement for displacement. I went with a 408.Lots of lowend TRQ. Plus a iron 408 is as solid as a Rock for spray or FI. My car is being put together as we speak. Will dyno tune and spray 200 shot Sat at G-Force dyno day! Will let you know Sat night!

383ss

iTrader: (14)

I've had a 383 and a 408 with a lot of different combinations of parts in each of them.

made 490rwhp with a 5.7 $1000 set of heads and baby 236/232 cam in the 383. the 408 made 550rwhp with a mild 246/250 cam and the same heads. you can definitely tell the front is a lot heavier, but it makes the power to make up for it and then some. I get better 60' times (1.42) at the track launching at 5k with the 408 instead of 6k in the 383 (1.50)

DrkPhx

iTrader: (15)

I was very close to going the 383 route, but decided to spend the extra dough and go to a LS2 402. No doubt it was more expensive, but I have no regrets.

Benjamin Russick

iTrader: (1)

My car is not a full-on drag car...it's lowered with suepension work geared towards handling, not launching.
BeardWS6: Sounds like a beast! I would love to see the dyno results!
383SS: You could actually "feel" the difference with the iron block's weight? Not good. That alone may keep me from going that route...
Thanks for everybody's help! I may have to start another thread with questions about the 402...

1BADAIR

iTrader: (1)

my car isn't set up for drag either. the prices are all about the same. I went with the 382 cause my block was good and machining was cheap. With the 383 you wil be able to use the heads you had. 402 you wil need heads for the larger bore. All things equal the more CI will make more power. 30's won't be enough. mine are maxed at 5500rpm. the 382 may rev quicker do to the pistons being larger on a 402 but I don't know if anyone would feel that. Its a toss up between the 402 and 382 but I wouldn't consider the 408 due to the added weight in a corner carver

383ss

iTrader: (14)

ya, it was noticebly heavier on the front end. much less 'lift' felt.


you do NOT need to get heads for a larger bore if you go to a 402/408. like I said, I used the same heads for my 383 and 408 and I'm putting down more power than most people.

PREDATOR-Z

Care to share your head specs, runner volume and valve size used?
And if I read correctly you are at 12.75:1 SCR, so I would say you better make 550rwhp

Benjamin Russick

iTrader: (1)

I'm beginning to think it may be a moot point. I've been looking at local shops and I'm beginning to think a direct long-block install would be safer that the assembly/machining to my current block. Sometimes I wish I lived in Texas...

383ss

iTrader: (14)

oh, its that easy is it??

I used a 2.02 intake valve and 230cc intake runner, 64cc chambers.
intake flow
.100 70
.200 149
.300 218
.400 264
.500 286
.550 292
.600 293

.600 flow numbers mean a lot too right

PREDATOR-Z

I'm not flaming, but slap on a set of heads that flow more across the lifts with bigger valves and same SCR and I'm sure you'll be at least another
40 rwhp+ and should tickle the 600 mark.

and take away the high SCR down to a respectable 11.0:1 with the same heads you have, you'll be ammazed how much you'll loose.
Your high CR is acting kinda like a boost by raising the cylinder pressures.

I just pointed out that it should not be taken for granted that bigger bore strokers do not benefit from bigger bore heads with more flow capabilities.

And .600 flow numbers mean a lot if you have a cam with lifts that carry in that range.

FUN LS1

The valvetrain is included in the long block. You usually get to pick the cam you want from a particular vendor the shop works with. The same is true for the heads. Also, there are options for valvetrain upgrades too. What's not included (but varies by source) is the intake, headers, etc. You know, the stuff you've spent years and $$$ putting on your car to get it where it is now. The key is being able to re-use as much as possible.

Benjamin Russick

iTrader: (1)

The key would be reusing the heads, which sparked the consideration of a 382/383 in the first place. If the cost and capabilites were nearly the same, I would always choose more cubes...

SAM98WS6

My LS1 heads flow a little better, same valve size but at 11:1 Im down some significant HP even with a much bigger cam just like you say. Nothing like that big compression ratio for big HP.

PREDATOR-Z

The cost of the shortblock are nearly identical between 382/383 VS 402/408
The difference is in the heads (and cam) unless you're running a huge cam for stock cubes which can be used as moderate cam for 38x cubes.

Like I said I'm planning a 383 myself, I can reuse my PRC 2.5s, keep high compression, upgrade my cam a couple of notches and stay aluminum with minimum expense.

Properly built, 500+ rwhp 383's are not that difficult and still well manered.

98Z28MASS

iTrader: (6)

I hear ya man, I only suggested forged 347 as another option as you said you didnt want to spend a ton of money on the setup. I mean if I had the money id def go bigger CI, just saying with a big cam that likes the spray (say trex or ms3) and your current heads you could make close to 500 rwhp on motor alone. The add a 150-200 shot and your over 600 rwhp. However if its more of a road racing streeet car and not a drag car id say go with the 402 ls2 as you will save a bunch of weight off the front end over a 408 iron block. Let us know though what you choose!

Benjamin Russick

iTrader: (1)

That's exactly what I was thinking...keep my Stage IIs, and buy a crank, pistons, ARP fasteners and a bigger cam. The problem now is finding a shop that could put it together...

The Alchemist

iTrader: (19)

I'm in the same boat as you guys. I make 420/400 with my TR224, long tubes and S2 heads, but wish I had more grunt down below 3500 rpm. I would love to see what just going with a 4.0 stroke would get me.

If I could get a solid 30ft/lbs of torque between 2000-4000 rpm over my current setup by switching pistons/crank/rods for roughly $3000 I would in a heartbeat.

I know everyone would say that I'd have to go 90/90, bigger cam, bigger heads etc etc, but I'm not looking for a high peak HP number. I would actually be happy if the car made 430hp and 450 tq peaking at 4000 rpm.

Any vendors want to chime in???? What's the cost of adding just a stroker crank and reciprocating assembly?

98Z28MASS

iTrader: (6)

Honestly you might be better off just buying a forged short block 347 from one of the sponsors. I believe FFHP or one of the sponsors is running a special, its like 2800 for a forged 347. That way you could still have your car on the road until the short block arrives then once you do the swap you could sell you stock shortblock on ebay or here because honestly once you put together the coost of all the parts plus needing to find a shop that can install everything your going to be facing just about the same amount and this way the short block is all balanced and ready to go.