need opinions (quick) on 383 build

[swb85]

Hey guys, I need some opinions here quick because I need to make a decision before Saturday. I found a complete 1969 4-bolt turbofire 350 in my area for sale. It's a complete motor, intake to oil pan and was running when pulled. The guy has it torn down to the bare block and it looks good enough to hone and slap back together & run. Block casting number is 3956618 and the heads are 041's (64cc chamber), but I don't know if they're 1.94/1.55's or 2.02/1.60's. I can get the complete motor, engine stand, extra stock HEI, extra set of longtube headers and extra weind stealth intake all for $350. My plans were to pick this up, sell what I don't need and slowly put together a somewhat budget-minded 383 stroker for my '85. What I'd like input on:
-Are these 041 heads even worth considering for a 383? If not, are they worth anything and what other relatively inexpensive options do I have? I want to run a cam bigger than .480 lift, so vortecs may not be an option.
-Any guestimate on what machine work would cost for the block work and maybe reconditioning the heads if I chose to use them?
-Anybody have recommendations for the rest of the motor? I planned on an edel thunder 650 carb, air gap intake, eagle or scat rotating assembly, weind water pump, msd HEI, moroso balancer, hyd flat tappet cam (specs depend on head decision), double roller timing set for starters. Good list? Bad? Suggestions?

Goals:
My '85 is the daily driver, so the motor has to be pretty reliable and pump gas friendly. Not looking for rediculous power here, just a stout little street motor with a decently lumpy cam. The current motor/drivetrain is listed in my sig, so I'd obviously want a good improvement over what I have.

Any advice? Good deal? Thanks for any input guys!!

[Jonboy]

I would say pick up the Scoggin Dickey Vortecs or the Summit ones, those thould be good for .540-.550 lift, and run under $700 a pair assembled either way. I don't think the stock 69 truck heads will be any good for what you are looking for.

[hiway]

The heads are basic 300hp types. Some dirt trackers will pay $200 or so for them. 1.94 valves unless changed. When you say budget minded, how budget minded? My budget:
Freshen heads-$200
Block work-----$300
Resize rods/bolts-$150
Cast Scat crank--$200
Hyper pistons----$200
Balance---------$150
Kit with bearings-$250
Cam kit complete-$250
I think the 280 Comp cam is a good compremise for the street with a 4 speed. It would really like a 750dp holley though. Keep the short block basic and spend all you can on the heads if you upgrade from this list. That's where the power is at.

[84 400]

^^ the estamtes above sound right on. The 355 you have now seems like a nice motor though and i remebr you telling me what it did to the trans. Still gonna keep the tranny i hope. Sounds like a great deal on that motor though and it is fun to build them up yourself. plus when done you can sell the 355 and make some money back. I belive peice parts has had some experiance with building 383 strokers so he may have some input for you

[piecesparts]

I have had some experience in the 383 field. I have had two motors made into 383s and there are defintie positives and negatives. Don't get me wrong, I really like the torgque a 383 makes and the response on the low end is phenominal.
What you have to consider, is the time and machine work worth it to you. I am betting that your block is what is referred to as a "Heavy Block", that is where there is a lot of material inside for machining. The way to tell this--is to look at the front block area (where the numbers are stamped) and see if the flat spot is a long metal piece that goes all the way up to where the intake meets the block. That is GOOD, the other style blocks can be machined, but they are lighter and don't take abuse well.

Look at setting yourself up for a motor that can run on the regular or midgrade fuels of today, or you will hate yourself later. I am presently at 9 to 1 in compression ratio, but the cam and heads make up for it. I am running DART II Sportsmen heads with the runner smoothed, but an aluminum head would allow you to go higher in compression , without detonation problems. The Vortec heads make some awesome power and I am working to get a set of those onto a TPI motor for my 91 Silverado. They can be purchased refurbished for about $500.00 a pair. BUT then you have to get the intake to fit that head--keep that in mind.

The cam is the whole trick to a 383, what is rough running and responsive on a 350 will be mild on a 383 (size does count). I am running a Comp Cams roller cam setup (#XR264HR-10) that idles fairly rough at the stoplights, but when turned loose it kicks hard. This required me to have a 2400 stall converter, so that the truck would sit at the stoplight without pulling it through while the brakes were set. I am also running a Performer RPM intake with a Performer Thunder AVS carb (650 CFM). I get a fair 14.5 to 15 MPG on the highway with a 700R4 tranny and 3.73 gears. Make sure you get the exhaust opened up to take the extra HP and keep the motor breathing well. I run an HEI that is set at 36 degrees TOTAL ADVANCE in timing and the air cleaner is a 4" K&N filter for free air intake.

I am running flattop pistons with a forged crank in this motor. The last motor had a SCAT crank in it and it stood up well, but when the #3 rod broke and made big holes, I scrapped it due to the dings on the journal and the fear of failure later. I also put in H-beam rods for strength, don't want a break in round two. I was running down the highway after a little 135 MPH run with a Camaro and the motor gave out.....Dang the luck.

I would build another today for my next project, but I am trying out some LS-1 ideas for my 68 Chevy truck project.

[swb85]

Thanks for the replies guys! I'm going to a couple machine shops for prices this afternoon. Based on what you guys have said and what I've been reading, I think I'm going to go with some aluminum 64cc vortecs that have been machined to accept higher lift. I'm planning on running quite a bit of cam in this motor (230-240ish duration) so I'll need over .500" lift capability. I have a couple dirt track racer friends, so maybe I can get a few bucks out of the stock 300 horse heads from them.

Right now I'm thinking Scat or Eagle cast crank, rods that'll handle up to 500hp and some flat top speed-pro pistons/rings and aluminum vortecs and airgap vortec intake. That should get me around 10:1 compression. I've already got 1 3/4" longtubes & 2.5" duals so the exhaust is taken care of. I'm keeping the 4 speed so I should be able to get away with a little wilder combo than an auto and still be very streetworthy. Right now my biggest concern is the machine work. Should I let the machine shop put the shortblock together or do it myself? I've never built a bottom end before, but have done tons of top ends. Any other input?

Piecesparts: If you need some LS1 help, give me a hollar....I've got more than a little experience with them.
http://video.ls1tech.com/search/asa/...1e00a493a3.htm

[piecesparts]

The ONE THING that is very important in putting a 383 together is the clearancing of the cam and the crankshaft. If you go too nasty on the cam, then you get into the crank's space. I would recommend that you get a good shop to do the lower end, so that they can manage the spacing as they build it. Stand right on to of them and get the experience there.

What have you done with LS-1s? The one that I have came out of a wrecked 2000 Firebird, with a 4l60E tranny. I am working on an install into the 68 Chevy truck with a set of 3.73 gears. I already have the adapter plates for the motor mounts and some of the throttle control cables. I would like to change the cam on this motor before the install is completed, to upgrade the HP a little. I saw a motor in a 64 Belair a few weeks ago that the owner is getting 24 MPG and with a small nitrous shot he was running with his late model Vette.

[swb85]

Originally Posted by piecesparts

The ONE THING that is very important in putting a 383 together is the clearancing of the cam and the crankshaft. If you go too nasty on the cam, then you get into the crank's space. I would recommend that you get a good shop to do the lower end, so that they can manage the spacing as they build it. Stand right on to of them and get the experience there.

I'm sticking with a flat tappet camshaft, so some clearancing will need done but not as much as if I went hyd roller. Cam profile won't get TOO nasty.....not enough to have excessive clearance issues. I checked around with some machine shops, told them my plans and they were very friendly and answered my questions/concerns. Having them do all the machining work and put the shortblock together & balance it is going to run right at $600. I plan on watching everything that's done so I can do the next one!

Originally Posted by piecesparts

What have you done with LS-1s? The one that I have came out of a wrecked 2000 Firebird, with a 4l60E tranny. I am working on an install into the 68 Chevy truck with a set of 3.73 gears. I already have the adapter plates for the motor mounts and some of the throttle control cables. I would like to change the cam on this motor before the install is completed, to upgrade the HP a little. I saw a motor in a 64 Belair a few weeks ago that the owner is getting 24 MPG and with a small nitrous shot he was running with his late model Vette.

I've got an LS1/4l60e in my camaro as well as my tahoe. I have tuning software (HP Tuners VCM suite) that allows me to scan/modify nearly every parameter in the car's pcm. It's a sharp learning curve, but after a couple years I've gotten a good handle on it. I actually tune some local guys' LS1's that have done aftermarket heads/cam/nitrous/converter. Haven't done a forced induction car yet though....that's a whole different ballgame.
Right now my camaro (in the video I posted) is right around 400rwhp/400rwtq through a 3600rpm stall converter and 3.23 gears. Haven't been to the track yet, still haven't got slicks on (1st & part of 2nd gear is useless on street tires). The tahoe is stock internals/boltons plus my custom tune. Shoot me a pm with any info you want. Lemme know your power goals & I'll tell ya exactly what parts will get you there (cam profile/compression ratios & all). Kinda funny how I learned things backwards.....figured the high-tech LS1 out first and now starting to learn the gen I sbc!!

[piecesparts]

Where in Topeka are you? I'm just 50 miles South of you in Lebo. I would be interested in seeing what you have done with the Camaro. What year is the car? Right now, I am working six 12 hour days at the Nuke Plant, but soon the outage will be over and Iwill have some time again.

Below is my vision of somewhat like I want to do with the LS-1 that I have. I drove this truck and it was a real HOOOT.

[swb85]

I'm a few miles north of town right off Highway 75. If you ever want to come up just let me know!!