Just wondering, always wanted to build a chevy 383 stroker, but now since I have my olds to do is it possible to build a stroker out of a 350 olds

 

You can stoke a SBO but it is a whole different animal than the SBC 383. You are starting with a good torque motor so its not really nessasary to stroke it anyway. Tell us more of you car , plans, power goals and budget. There are many on here that can help direct you.

 

Kinda talked about it earlier in the summer.Well I have an 77 cutlass supreme brougham, which my father bought new back in fall of 76. I want to restore the car. Found out the 77 engine isn't the best, so I found a 76 cutlass 350 complete. What I want is a solid 400HP and what ever torque I can get, going to be a Saturday night cruse car, take it to the strip once in a while, just have lots of fun with it. I want to build this car and have it last a long time so I want to do it right and I want to use the 350. Budget wise don't have one and don't want one, I just want it built.

 

Had two 380 builds, one early gas block , then a DX. Currently the DX now displaces 425 cubes.

 

is the DX block necessary, or just preferred?

 

I've done 2 of these, first one was 4.125 bore with the stock 3.385 stroke, 362c.i., ran great.
Next one was 4.125 bore with 3.5 stroke for 374c.i., also ran real good, real snappy. Both used SBC rods and pistons, cheaper, lighter, better than what's in there now. With a 4.155 bore it'd be a 380 like Nicks'. With a 3.6 stroke it'd be 390.

You can bore the earlier blocks (68-72 especially) to 4.155 easily and stroke the stock crank to either 3.5 or 3.6 as mentioned fairly easily as well. No pun intended but it's not Rocket science and they respond real well to the mods. With a decent set of heads and the right cam 400 hp is real obtainable.

 

I preferred the DX but it is more costly.

 

This comes up every so often and is a product of our Chevy-centric world. There's nothing magic about a 383 cu in displacement. It is popular in CHEVY motors because it was easy to drop a 400 Chevy crank into a 350 block and voila, you get 383 cu in. All Olds small block motors use the same 3.385" stroke, so there is no easy drop-in stroker crank. More to the point, for a fraction of the money you'd spend building a totally custom 383 Olds, you can simply build a stock 403, which is externally identical. Even more to the point, a 455 Olds is a bolt-in replacement for a 350.

 

I still call the Olds 455 one of the first "stroker" engines. They simply took a 425 bore of 4.125", added some stroke to make 4.250. There you have it, long stroke, smaller bore plenty of low rpm torque.

 

There again Joe, some of us don't want a 455.

 

Good, more for me.

 

How do these engines hold up to abuse. 350's are hard to kill, but changing the guts of the beast,do they hold well together as a 350 comparing the 383 and 350 would be running that 400 hp area

 

My first 380 used a 330 crank in a 70 gas block with a 3.50 stroke 6.300 Manley rods, with JE custom pistons. Made 518 HP and raced it for 3 yrs. When it was tore down to freshen up, #4 main was cracked. What we figured happened was that I was using only solid motor mounts (with no motor plate) and was launching @ 5000 rpms. Can you say "Twist and shout?"

 

Holy f^$%. So if a person were to spend from 4 to 6 g's is this possible

 

you don't use 400 crank in an olds to build 383 stroker or you can use any crank from a SBO's- the 350 crank

 

All SB cranks have a 3.385 stroke. You have to off-set grind the crank to increase the stroke. A lot of expense came from the rods and pistons. The rods cost me $600 and the pistons (custom) a little over $800. IIRC it cost me around $8000 +/- total.

 

I did a stroked SBO with the Chevy parts for a friend, top to bottom $5300.00

 

what was your torque rated at? You build these strokers yourself or is there a shop that knows alot about olds engines and build's them. What would a person get for 6 g's in an olds motor

 

How does the chevy parts compare to olds parts, same s&^$ different pile? What HP/torque did you get

 

Ddin't have access to an engine dyno at the time, but I do now. My guess would be around 325hp/375tq. Heads were close to stock, plus he had the old style Performer. But good carb, decent compression and an ample cam with 1.7 roller rockers. Insides were real light and strong, revved quickly.

Pm'd you on what you could expect for about 6g's.

 

Here is the DX build;

DX block bored to 4.155
Program Engineering 4-bolt main caps, Main spacers from BTR
Main restrictors along with lifter restrictors
Mondello oil pump
Milodon windage tray

330 crank off-set ground .115 for a 2" rod pin and a 3.50 stroke
Manley 6.300" SBC Tour Lite rods with a .927 piston pin, 536 grams
JE custom pistons, .050 dome.....465 grams.....pins 116 grams
Clearences:
Rods.......0025
Side .......0027
Mains 1-4 .0030...#5 .0038
Piston to wall .005

#7 heads.....2.10/1.71 valves
milled .045 results in 12.75:1 compression (.010 deck hgt)
Flow 270 intake.....208 exhaust
1/2" head studs
Cometic head gaskets .040 thick......4.185 bore
HS rockers with 7/16 studs and guide plates
Jomar stud girdle
Comp springs.....160# seat 440# open pressures


.921 solid lifters (Crower I think)
UD cam specs:
.576/.593 lift
256/263 dur.@ .050
108 LS installed at 102
Hex-A-Just timing chain
ATI damper (external balance)

Modified Victor intake
950 HP carb 84 jets square, no PV
1" Super Sucker spacer
MSD ignition....33* timing locked in
Meziere water pump
Kooks Jet Hotted 1 7/8 headers

Produced 598 Hp at 7000 and 523 TQ at 5100

This is in my 70 Supreme. 3350# race ready
5400 Coan Converter, 400 Turbo w/trans brake
Narrowed 12 bolt Chev.....5.14 gears
14x32 slicks

The car ran 10.60 @ 124.16 mph with a 1.43 60'. 2700' adjusted altitude. Zero ajustments only had 2 time trials before eliminations.

 

WOW that is a lot of *****. A little to much for me. At least 160 HP less for me. You use #7 heads, why not #5's. Where did you get your heads port and polished and punched for bigger valves. If I had low 400's to 450 hp would I really have to bother with a DX block or is that just meant more for your style of racing?

 

I think I can answer for Nick. For 400+hp you don't need a DX block. When you race, your launches are what stress the block and internals, the more grip, the harder it is on everything.
Most areas have reputable shops that do porting, I have one 2+hours from me and there are other vendors here that will help in that operation as well.

 

I'm just blown away by the 5400 stall & 5.14 gears! Definitely not for street use

 

Yes Mark you are correct, thank you. Kyle's 77 I posted this basically to let you know that all the internals and heads etc transferred from the gas block to the DX for future use. I had a pair of #6s and two pair of #7s. The one pair of 7s started out being home ported over many years time. Finally took them to an Olds head porter who got fantastic numbers out of them but also turned them into a sprinkler system. I have found get some one to do basics and you will be happy.

71, this thing hasn't seen the street since 1984.

 

can you say severe whip lash.love it, good thing she don't come with wings or 380 would fly. lol