Known Information of build , vehicle use.
'75 350 never opened, Replace heads with new castings of Edelbrook.
roller hyd. cam , flat top pistons(?) (options here?) no crazy overbore. say standard 30 over
Automatic2004r, 2400-2800 stall, 3.73 gears, 28" tire. 3800 lb's.
95% street use.
And go.

 

What are your power goals? The mid 70's Olds 350's from my experience, owning multiple examples, working on them in shops when there were still some on the road, were the best GM 350 or any make in similar sized motor from that time. It may have little wear on the bores. Cutlassefi brought a nice 10cc dish 1mm ring pack Mahle 4.065" hone to fit pistons the market. If you want more compression, Bill Travato brought a CP forged piston in the same size but 1.5mm ring pack but small 1.3cc valve reliefs. I have my 76 block at the machine shop right now, hoping it will clean up the .008" as well.issue, One issue if you want to push 10 to 1 compression, which flat tops will put you there with a roller cam, meaning an easy 400 to 500 hp, is the stock lightweight crank. On 73 and up motors, my 73 350 has one, GM put gray iron cranks in versus the Nodular or N crank. We saw a 400+ hp Olds 403 with a manual trans break on in 3 pieces on here! With the modern lightweight pistons and stronger along with lighter aftermarket rods with an internal balance, the stock crank would probably hold up. But if you are pushing 6500 rpm a lot of times and just spent thousands, do you want that to be the failure point? The N cranks are still plentiful and even the forged steel 330 cranks are around, I have 2, so they are out there and still affordable. Cutlassefi also brought a 4" Billet steel stroker crank to market, even with iron heads, 400+ hp and 500+ ft/lbs is what they have been putting out in the mildest form. Good luck, plenty of different ways to go. And the 2004R will need many upgrades and someone who knows them to build it. I figure $1000+ in parts alone to live behind my planned motor. If Dr Dan Mascal wasn't basically chased from this site, he is one the experts here on these trans, he has built cars in the 9's with them. A nice Olds guy, was always helpful to me and others. I have the big CK Performance book, a lot of tricks in there and plan on taking the plunge myself. Our local trans shop can't build a 4L60E to live behind a stock 5.3, so no, they aren't building my trans. I have a spare 2004R and will get the parts through CK Performance. It sounds like a nice plan, good luck.

 

That’s a good overall concept. Depending on your budget the most beautiful thing out there is Mark’s stroker kit, great bang for the buck. If not looking to go quite that deep in the pool the offerings available for SBO have never been better, not even close. Even keeping 350ish ci you can build a nice running, responsive engine. Remmel, Rocket Racing, BERNARD Mondello, Trovato if he’s interested, Dick Miller, and there are others on this forum that you should pick from to get a detailed plan in place and execute it.

 

Is that really a valid comparison? I thought the 1977-up cranks were lightened (and therefore weaker) than the 1976-older cranks.

 

No, the 403 was an extreme example. Anyone have an N crank weight? I can weigh my 76 crank. Even though my 73 crank doesn't have the N on it, it does look beefier and different than the 76 crank and other lightweight cranks I have seen. My 76 crank looks identical to the 78 403 and 83 307 crank I have had in my hands, not strong looking pieces and noticeably lighter than my 330 cranks. What does a good N crank cost, $200 for the core? It seems minimal to me, again it depends on his goals.

 

Guys no over the top overbore, no stroker kit. Crank and rods in it get used unless a mag test shows issues. Rods will get new ARP bolts.And A roller hyd cam and pump gas compression that allow/work with 2400-2800 stall and 373 rear gearing. on the street and run/idle without fowling/loading up the plugs.
Budget?
I know the heads will eat 1200-1500, the hyd roller is I would say a guess of 1000.00 +/- (cam lifters,push rods and springs if the delivered edel head springs are a nogo with cam)
deck block if needed to get good squish numbers and pump gas(super 93) compression ratio.
It isn't going to be a 2000 rebuild, but not looking to have a 5000.00 pile of receipts either.
If I want cubes I would start with a 455, or the 632 here(bbc)
Cars use is street cruiser Not strip bruiser.
I never worked over an olds and have know idea where the hp level will land on a 350(355) olds and work with the stall/gearing.
If 400 hp +/- is a reality, fine if not 325-350 hp. My idea for vehicle of 95% street use means it needs to run/drive like you would be able to drive it every day other than in winter, if you wanted/needed.
I'll give up a glory peak hp number for a fat torque and long slope hp curve in this vehicle , So I can be in the drivers seat more than under the hood.
I have a 632 bbc If I want nutso power and upkeep.

p.s, I am ASSUMING a need for a 30 over bore. If it doesn't NEED it, fine. core 350 has 78 thousand Grandmother filled miles on it. Can't pick over bore size till opened up and measured, but pump gas compression with the edel alum. heads.

What I don't want is a engine that is a A fartin mess at idle, somewhat gutless till 3500 rpm, then goes like you set off a bomb. needing a 3500+ stall . I have one of those. It is fun to drive till you get stuck in slow moving traffic of any kind or sit still, idling. As you have to play romp the throttle every so often to clear it out to keep it from stalling. I plan on driving this a lot more than a week end only cruiser, but not as much as an every day daily.
I figure the edel heads and a hyd roller cam will help get more out of a pump gas power and not be a pain service wise and why hyd roller and not solid roller.
It will start with a q-jet and maybe move to port efi, but that is a big maybe. So figure a rebuilt q-jet.

 

I am not up on all things Olds , but from what I have read, the '76 up 350's got the lighter windowed blocks and parts.
I don't know what a 1975 350 has for a crank, But I doubt it was a forging at the power levels they had.

 

All I know is my 76 crank definitely looks the same as my later cranks I pulled out. My 73 crank looks psychically beefier, different colour but still has no "N" on it. Bill Travato claims the 73 to 75 cranks could be either but his book has some errors, especially on dates. Will it fail, probably not but a 10+ to 1 Olds 350 with a healthy roller cam will pull much more than 5000 rpm and make 450 hp+. With modern 350 pistons and rods are way lighter than forged 403 pistons and their heavier rods pushing past 6000 rpm in a flimsy block with the shock load of a T56, so a big difference but it sure looked like the failure point. With a good internal balance it may last forever, dou you feel lucky? Take some pics when you strip down the motor.

 

The first thing you need to decide is whether or not you want 325-350hp or the 400 you mentioned as well.
From there you’ll need a good base, an N Crank and better, aftermarket rods would be a wise investment. The rods are just slightly more expensive than the cost of rod bolts and reconditioning the stock rods. In addition the new, more modern pistons will offer added HP by way of better ring packs and skirt designs.
Your estimate for head work is probably pretty close though, however again depending on your ultimate HP goal.
Hope this helps.

 

Hp goals are as much as I can get out of it, BUT be able to use a converter no looser than "claimed" 2800rpm.
And it have ok road manners as far as wide rpm band, and not having to play throttle jockey to keep it running.
Love to have 400+. but not if it is going to require a 3500 stall converter and 410/411 gearing to get out of it's own way .
This will be built starting next fall. As I plan on enjoying the car this season as it is. The funds are already put a side.
I know you helped get pistons made, but have no idea of the part #'s and what bore sizes are avail in that line.
Are they hyper or forgings,
Rods. What is out there that isn't big money custom oliver type. Again first olds. no idea who makes what, and who's parts are junk .
Figure a red line of 6000-6500 if that. Again street cruiser/car. not going to be winding it to the moon all the time. but still want to be able to have fun when , it is an option.
I know with Pontiac the rods you don't even think of using.
Totally green on olds. So, think of me as a newbie. as far as when to goto better rods and crank.

 

Here is a combo I ran for about 3 years. I sold it but it's tried and trued. About 370 ish HP. Low buck basic nothing exotic. I would drive this set up to the track 60 miles race all day and drive back home. The car ended up running 12.20's https://classicoldsmobile.com/forums/small-blocks-3/what-do-i-do-now-98060/

 

1977 is when the windowed blocks were introduced. The 350 used the same block casting (395558 2) from 1968-1976.

 

For a converter with the 2004R, the Dr Dan Mascal Nitrous 2800 stall converter from PTC is the way to go. Dan said it is nice and tight around town but flashes right around 2800.

 

I have a 2004r and converter from the Real Art Car.

 

I'am with the DR on this: PTC