MyFathersOldsmobile

Hi All,


Doing a budget 350 build using mostly olds parts. Ran them through CompCams camquest software. Wanted to see if I'm on the right track and if these are realistic. Here's what I've got/ am considering:


1976 Olds 350 bored 30 over
1972 7a heads
Stock #16 intake
stock 262/274 olds cam (as recommended by an Olds builder for my project)
Cometic .032 compressed thickness head gaskets
Speed pro Flat top pistons with 5.8 CC dish

According to the calculators, I should have:

295 HP @ 5000 rpm
375 lb/ft torque @ 3500
9.86 static compression
8.06 dynamic compression
able to run on pump gas


calculators are great, but real world is better.


thanks!

coppercutlass

Cam quest is so far off its unreal. There is plenty of proven combos on here here with your hp goals. The biggest thing is making the whole combo work . Like gear converter etc etc.

MyFathersOldsmobile

I just looked around on here and saw what others are using for their combos and what I'm considering is really close. Saw one post whose set up is extremely close to what I'm looking at running high 13's in the quarter mile. Think this is what I'm going to do. Thanks!

coppercutlass

I have had a few diffrent combos with small blocks. running 13.8's 13.3's and currently 12.6's all budget builds.

olds 307 and 403

You won't be anywhere near 9.9 to 1 with those pistons unless 0 deck and the heads milled a good amount, not talking a clean up mill. I would think you will be around mid 9's compression, unless you want a premium fuel only car. Talk to Cutlassefi for the cam and use the Performer RPM, much better than the stock intake and way lighter.

MyFathersOldsmobile

This is what I was after! I've heard that the online calculators were off. This why I asked. But, I think I should explain what I'm trying to do. I want to build a sleeper. Wire wheels, stock parts, the whole shabang. I will never go to the track and probably never go to the dyno. I was going to take Stock 350 and build to olds specs and call it done. Going for a look. That's why the stock intake. "Oldsmobile" In big letters on the runner. I Want it to perform like my '11 Silverado. Good manners yet quick off the line. However, I just happened to stumble across this engine that I guy wants out of his garage. Bored 30 over, balanced, and comes with flat top Pistons. Did 11's in the 1/4 mi using alcohol. Has only a few hundred hours on the rebuild. Bearings still look new. Valve train, heads, and intake are gone. So, if I can use the flat top Pistons and still use pump gas, I'm all about it. The only piece I dont't have is the cam. Heads were rebuilt to stock specs so, I really don't want to change the springs if I can avoid it. I know this sounds hokey, but the are a quite a few "show builds" around here. Nice, but not my style. I'm more of a "wait, you have what in there ?!?!" Kinda guy.

1BOSS83

What exactly does that mean? I ask that because the traditional definition was a car that looked unassuming and could shock em' at the line. The kid with the 4.6 mustang and SLP's gets smoked at the stop light by the 86 caprice with the 454 and thursh's. The cars of today have changed the game. These engines require the time old formula of compression + displacement and air flow (for a budget build). File off the Edelbrock logo, paint it black and get a big air cleaner because the new turbo 4 banger mustangs are 300 hp+ and I promise you that no one will know what they are looking at.

Chesrown 67 OAI

you will never achieve 295hp with the combo you listed. throw away the 7a heads to begin with if you want a chance to get where you want to be. And is see you are looking at others here that "have gone and been where you want to go" and thats a good thing. listen to people you can trust and wont BS you. Good Luck with your build.
P.S. You can get where you want to go with 9.0-9.25 compression and have agood pump-gas motor!!

coppercutlass

I ran high 13's with 7a heads 1972. Stone stock heads freshened up, stock 73 short block and a comp 26th cam. The 72 7a heads are just as good 7 or 6 imo. Similar to the op's combo but less compression and less can.

MyFathersOldsmobile

Copper, thank you. To all, I appreciate your input, but this isn't about how much power can I make. Rather it's about how much bang for my buck. Sure, I could spend a grand on aluminum heads, another 500-600 on the best cam and lifters, and 300 on an intake. For what?something I'll never drive because I spent all the money on parts. This is about me enjoying my car. Isn't that what it's all about? I think I've done my research and cherry picked the best parts olds had to offer. I've scoured the Internet waiting for parts that no one else wants, roamed through bone yards looking for the perfect part and I'm just about done. want to know how much I have in this project? $630. Want to know what I have?

1976 350, bored 30 over with maybe 500 hours on it.
A balanced rotating assembly with trw 2320 flat top Pistons with rings and bearings.
1 set of 7a heads rebuilt to stock specs less then 500 hours ago.
1973 cast iron manifolds
#16 intake that came off a rebuilt 350 in a bone yard.
A 1973 complete 350
A th350 core
And a bunch of little parts that I will be selling once I'm done.

All I need is a decent cam that will work with what I have. If I need to, I'll change the Pistons to drop the DCR. But, honestly, it makes me cringe because they are $400. But that I can justify.

Again, I appreciate everyone's input, but I'm not building a ground pounder. Just a car that I can be proud of.

coppercutlass

That's how all my builds are. Bare bones low buck. My current build cost 3500 has iron heads etc etc. Not bad for a mid 12 sec sbo. That build I mentioned earlier was very low buck. Don't think I spent over 2500 and it's still in service in my dad's pontiac

1BOSS83

So lets talk numbers. What do you want to spend?

coppercutlass

With what you have you can you can have a very respectable power plant. I would find a used performer rpm. I have one but its been ported to match my ported heads. I have decided to go to a holley street dominator intake for that engine build. If you want the performer i can sell it If you plan on having atleast 9.75 to 1 compression i have a howards cam i can sell you . It was used in one of my engines but it was properly broken in and has new lifters so will have to be re broken in. The howards cam is a 512/512 lift 227/234 duration on a 110. I also have some roller tip rocker arms i can sell.

You can have it all for 300 plus the shipping. If you have an 8.5 10 bolt i can even sweeten the deal up by throwing a 3.73 gear for free. Just pulled it from my 72 as i went with a 3.90

You can have a serious fun street engine with what you have. just make sure to back it all up with a good converter and gear.

MyFathersOldsmobile

I just got off the phone with the guy who built this engine and the heads. He's a retired engine builder who has a soft spot for Olds. He told me how to get my CR numbers down pretty inexpensively and said once that is done, I'll have a respectable little car with the combo I have. Won't be 295 HP, but that's not what I was after anyway. That is just what an engine calculator told me.


Copper: Thanks for the offer, but I'm going to stick with what I have for right now. Once it's in and running, well, that may be another story.

coppercutlass

I figured i would offer. I have this stuff lying around i keep saying im gonna use but then there is always a change of plan. Planned on using the rpm ditched it for a single plane , planned on using the howards cam ditched it for one that would take advantage of my flow #'s on the ported heads , Was gonna use the roller tip rockers and got some full rollers for free .


Goodluck with the build keep us posted.

MyFathersOldsmobile

Thanks, it is very much appreciated. I know what you mean about parts lying around. I've got a 2BBL intake and 2-#8 heads from the 350 I tore down. Unless anyone can knows of a reason to keep them, think they will wind up in the scrap pile. Even they don't want them!


Oh BTW, in case your wondering, I do have an 8.5 rear. Got a rebuilt one out of a GN with 3.42 gears. Gotta love craigslist!

MyFathersOldsmobile

The offer was appreciated. I know what you mean about parts lying around. Got a 2BBL intake and 2-#8 heads off the 350 I tore down. Can't see a reason to keep them. Probably wind up on the scrap pile. But, even they don't want them!


BTW, in case your wondering, I do have a 8.5 rear end. Got a rebuilt one out of a GN last year. Gotta love Craigslist!

GEARMAN69

Is it going in a otherwise stock G body Cutlass

The 260/274 cam (4 spd cam for low compression 350 4 barrel)

at 9.2-9.5:1 would drive good and be high torque with a stock stall and stock 2.56 gear

if thats what you want.

I guess you mean this cam below (also is a 455 auto Toro cam)

( 402486 48 262/274 .440/.440 350 ST M15, M20 )





but please as long as it is not this cam

400084 36 250/264 .400/.400 350 2BC, 4BC AT

Kill me now

I still have not assembled my similar compression combo but will be using this 68 400 4 speed cam

393859 58 286/286 .472/.472 400 ST ex. OAI

That is also listed as a correct 70 350 4 speed cam

393859 58 286/286 .472/.472 350 4BC ex. AT, OAI, hi-perf

I feel like it is the true 310 hp 350 cam but would like a 2200-2400 stall and at least 3.23 gears in a automatic I imagine.

Joffroi

For what its worth, I had a 1972 Cutlass Supreme that had a 350 from a 69 Cutlass. Unfortunately, I don't remember exact details from the car (sold it a few years ago) so I don't know if this will be useful but I dynoed these numbers are the results:
HP: 274
Torque: 287

'69 350 block
Edelbrock heads/ported
Edelbrock intake/matched
Custom cam of unknown duration
Coated headers
Pypes 3" with X-over
Billet acc. drive
Eletric Fans/Fuel pump
New Battery
700r Trans
3.73 12bolt posi

woodie582

I could send you my build spec sheet. 71 350, budget build 0f around 3,500. HP 287 tq 327.

droptopron

For what you want def think transmission & gears. Maybe a four speed auto with 3.73's.

VC455

I used a 393859 cam in a 1970 350. The cam is old tech now, but in a Vista-Cruiser 35 years ago it was indeed a sleeper.

GEARMAN69

I am eager to use the 393859 in my 70 with the M20 / 3.91 combo figure it will be quick even with a lower rpm launch since it wont be over cammed

GEARMAN69

Rear wheel Dyno ?

GEARMAN69

Rear wheel Dyno ?

woodie582

Yes rear wheel.

MyFathersOldsmobile

Hi All, sorry been a busy week. But, to answer a couple of questions:


Gearman69: Yes, it's an otherwise stock G-body cutlass. For the most part. The stock 7.5/2.56 rear was swapped for a GN 8.5/3.42. Yes, Cam #402486. I did look at the #393859. From what I can tell, the two are pretty close. One makes more torque, the other makes more HP. Please correct me if I'm wrong. And, "OH H#LL NO" to Cam #400084.


Joffroi: It does help. It gives a good feel for what I want. I was planning on a 2.5" exhaust for now and if I change the trans, I'm going to go manual. So, I have to make sure the crank is prepped for it if I decide to do it down the road.


Woodie582: Yes, please do send be your build. That's why I'm here. I want to see what others have done so that when I get finished, I'm not disappointed.


Droptopron: Already looking to the future. But, am going to wait until the stock 200r4 gives out.


vc455: Nice. I don't mind old tech. I'm not going to the strip or the dyno. Maybe roast a tire here and there.


Thanks everyone! your input is very much appreciated!

olds 307 and 403

I run at 60 MPH with 3.42 gears and short 25" tires around 1850 rpm with a locked up converter with the 2004R Trans. The stock converter will flash stall around 1900 rpm.

coppercutlass

i dont think i posted my combo.

Here goes.

350 .030 over with speed pro flat tops .025 in the cylinders . 10 to 1 compression

#6 heads with 2.07 in. 1.63 ex. valves milled .024 no port work just opened up the bowl .

Lunati voodoo cam 522/539 lift 233/241 duration @ .050 lift

Previously ran prw roller tips went to full rollers from prw , Pro gear timing chain

Edelbrock rpm intake topped off with a box stock 750 holley 3310 vac sec

Proform hei curved for my set up

engine built by myself No special oiling things done stock bbo pan and stock oil pump. main clearances where .0025 and rods where .003

Trans is a th350 with a 3000 stall Trans was built by me tq. converter came from an ebay vendor. ( winners choice transmissions )

rear end was done by a local olds racer was 3.73 previously just went to 3.90's

Car is all steel ran 12.62 @ 106 mph in the 1/4 mile.

MyFathersOldsmobile

Whoa! Thanks Copper! That looks really close to the formula I want to use. The engine I have actually has TRW flat tops in it. I was going to swap those out because I was concerned that the compression would be to high to run pump gas. I also think I'm limited on my cam selection has even though the heads I have were rebuilt, I think I need to stay will less then .5 lift with stock springs.


307 to 403: Thanks! I was going to run 26" tall tires (stock tires on GN wheels) so, that should bring my RPMs down a tick. I'm thinking anyway.

olds 307 and 403

Go with the bigger of those two cams, even that will be too small . What octane do you have around there? Don't over look the #8 heads, just needs the bowls opened, especially on the exhaust and a 2" or 2.07" intake valve to equal and surpass those 7A heads. With a reasonable mill you will be right around 9 to 1 compression with that short block.

MyFathersOldsmobile

the highest we have around here is 91 octane. I did look at the #8 heads and when I played around with the online calculators (and yes, I know they are not very accurate) It dropped my DCR to around 7 and it is my understanding that performance engines run best on pump gas with DCR's between 7.5 to 8.5. However, if I use the 268 cam and my flat tops, my DCR will be at 8.2. Little on the high side but doable. It will give me a SCR of 10.25. Thoughts? Overthinking it?

captjim

Keep in mind that there are a bunch of factors that will affect the DCR. Static CR is fixed and something that you can measure and calculate. Cam timing, intake and head flow, barometric pressure, ring seal are just a few.

olds 307 and 403

I have 9.5 to 1 with the Performer cam, 280/290 advertised duration, 1.72 roller rocker arms and very cold NGK 5670-8 spark plugs and it is very finicky. If anything is off , including shitty weather, it pings. You will just ping constantly with a small cam and that high of compression.

jpc647

It'd really like to see this, especially where you said it was a $3500 rebuild.

MyFathersOldsmobile

I kinda figured that. I was just hoping to get in the ball park. But, from what I'm reading, doesn't even look like I'm in the parking lot!

MyFathersOldsmobile

Thank You! This is what I was looking for! I was actually broadening my horizons and looking at lunati street master cams. 276/286 advertised duration. But, it kinda sounds like that wouldn't even work with what I have. It also tells me that those online calculators are WAY off (yes, copper, I know.) So, that being said, I may have to go back to my original formula and change my pistons. Oh well, not the worst thing in the world.

80 Rocket

I don't think I would agree with that assessment. The #8 heads, as well as BBO J heads have a completely different runner than previous predecessors (very different head). I have done extensive testing with a J head and found the results to be less than fruitful (not bad, but definitely not earth shattering). I did find gains down low on flow testing, but I am unsure on the short turn as of now.


I haven't come to any solid conclusions yet, but I believe Olds was definitely trying to do something different with the #8 and J heads......and maybe it was to promote swirl. But I am on the fence about them being a better head than the previous heads out there. Even with opening the underside of the exhaust, they still flow pretty bad.


This Thursday I will have some numbers on a stock 7A head. We will see what happens.

80 Rocket

Here's my combo that went 13.02 @ 104mph in a 3500lb 78 Cutlass (weighed on 4 corner scales with me in it).....


- 1973 short block.....stock pistons (14cc dish), stock rods, stock crank, 9:1 compression


- #7 heads with small valves and no porting (1.875/ 1.562), stock rocker assembly


-Lunati 318A3 cam (221/230 @ .050 .485/.485 lift)


- Perfomer RPM intake


- 650 Holley double pump carb


- Stock pan with hi volume oil pump


- 1 3/4 headers with X-pipe and full exhaust through mufflers


- stock fuel pump with 5/16" fuel line


- 200-4R trans with 2200 stall and 3.73 gear and 26" tall tire (235/60/15) Mickey Thompson ET Street drag radial


Nothing trick or fancy. Just basic stuff. I had a very good short block to start with. Drove it down the freeway to the drag strip to win races, then drove it to the bar to celebrate. It was also my daily driver for a while in 2006. I loved that combo. It also won me an index racing championship in 2010.

olds 307 and 403

The port doesn't look too bad, I would love to see data. The J and 4A are just plain terrible under exhaust valve. Those two without hours of grinding flow what 120 cfm stock? He already has the #7 heads done and should just change the pistons. I think going with a big enough cam is key, my #6 heads will flow way better than the stock heads in 80 Rocket's car but I am over a second slower. With 300 more pounds, slightly less gearing and a 204/214 cam, even with 1.72 rocker arms, maybe even my Qjet and shifting at 4500 rpm no doubt made the difference too.