deadeyejedi

ive been messing with the 72 cutlass 350 for a while now trying to get some responsiveness off the line with no luck .i installed a new hei with adjustable mechanical advance and played with a bunch of settings on that with really no change .my initiall is set at about 18 with the advance plugged .ive moved that all around as well .i first thought it could be torque convertor but most members ruled that out .my accelerator pump seems to be pumping fine .could it be primary metering jets ? i did a basic carb rebuild when i redid the car two years ago .ive never owed a 350 rocket that wouldnt light up the tires when you stomped it .thanks for any input.

olds 307 and 403

Even with 2.56 gears, it should. That is the stock 8 to 1 motor with the tiny cam, it doesn't help. Does it have dual exhaust? Is it a 2 or 4 barrel? More initial, like 20-22 won't hurt and 36-40 total is a good range and 38-40 will feel stronger on the street but will run slower at a track. Did you try foot braking the stall, it may be stalling very low. Maybe get a recurve kit and try lighter advance springs. I always found the Olds 350 adequate no matter what it is installed in. Did you check the block casting numbers? You would be surprised how many people swap in 260's.

deadeyejedi

It's matching numbers block around 80,000 original miles with headers and 4 bbl quadrajet .if you try to power brake it simply does nothing but bog . It will go like hell once it gets rolling .im thinking carb related I may bolt on a different carb and see what happens . Thanks for the reply

lemoldsnut

Biggest seat dyno bang for the buck will be regear it. Like 3:23 or 3:42 would make it still ok on the highway and drastically change the out of the hole experience.

Just my 2 cents

Larry

deadeyejedi

I agree but it should still do a one wheel peel with 272 rear.

coppercutlass

Not really imo. I went from a 2.41 to a 3.08 on my dad's pontiac bonneville with one of my old olds350's . It runs strong but wont burn rubber. That car appx sits at 4k lbs which is close to the gm A body fully loaded.

You wanna talk about bog. My 350 olds in my car ran 13.7's. and would lay rubber down like no other. On my dads car with the 2.41 it was sooooo under geared the engine would shake and sudder under light acceleration. I got the car tuned pretty good with the 2.41 and it ran ok but once i out the 3.08 gears in , re curved the dist., and re set the carb it ran much better . it wont do a power brake burnout but it goes for what it it.

You will be amazed how much a gear can hold back an engine that wants to go. Kinda like trying to run in quick sand. Now if it was a 455 it would be diffrent as it packs alot more tq and does not need as much gear like a small block to really get going.

GEARMAN69

Simply the stock 72 spec with likely 2.56 gear and stock stall , the 8:1 adv comp and the tiny stock auto 187/200 @ 050 cam all make for a dog expecially off the line. Best thing you can do is at minimum a cam , converter and gear swap and better yet later a piston swap or install and milled down set of #4 330 heads if you left the block in for the cam change and convert/gears to go with the headers you have. Easy thing is gears first

olds 307 and 403

As said above even a 3.08 gear along with a 2000 stall would make a big difference.

GEARMAN69

^^^ Yes as he said first but also re check your secondary choke pull off that it is working and how lean the secondary rods are. Likely needs to be richened and if the pull off is bad it will open too fast and bog besides also a possible lean bog

70sgeek

It's tough to squeeze a lot from a stock specs 80k mile motor - depending on budget, I'd vote at least for new performance cam/springs kit, a good 2x roller timing set and maybe a slightly performance-modded Qjet to wake your motor up. As also suggested, 3-series rear gear definitely a good upgrade along with those.


I basically started with a similar setup as yours - a 50k+ mile '72 CS 350 which started life as a 2bbl motor, now 4-bbl with hi-po cam, HEI, flat top pistons, E-brock intake and slightly modified '76-vintage Olds Qjet, etc. 3.08 posi replaced the 2.56 open as well. Also running approx 2300 stall and 2.25 dual exh.


Running same timing figures as you, and it was a pretty huge improvement

RROLDSX

Bad gas? Something is not right IMO.

442fanatic

A lot of good advice on here on the direction to go. I have been in your shoes.

Rebuilt a olds 350 with a better cam, better pistons, true dual exhaust, headers, eventually a different carb tried an E-brock 650. While some of these changes helped, especially the dual exhaust and headers. The biggest change is the rear gear. I went to 3:42 and it was great behind the olds 350, a bit high for the 455, but fun.
Next would be the cam, timing set, distributor overhaul, intake refresh carb........ stop when the $ runs out or ya get sick.. laugh

Greg Rogers

My 71 Cutlass-(350, 8.5-1 compression, 4bbl, turbo 350, 2.56 rear) is a dog. It runs fine- nice and smooth but..... a dog. I rebuilt the engine completely back in the 90's and I was so disappointed with how it ran. I have messed w/timing, carb adjustments,etc. etc. It's just what it is. My 70 Vista cruiser-(350, 10-1 compression, 4 bbl, turbo 350, 3.08 rear) is completely different. It is much more responsive, even though the car weighs a lot more.

76olds

Olds 307 and 403 gave you some good advice, FWIW I put a 3:42 rear gear along with a TCI Saturday night special Torque converter in my 76 , it was well worth the $$ spent IMO.
Hope this helps
Eric

deadeyejedi

thanks for all the advice .and i completely agree that gear change and cam change and engine upgrades will make a big difference,but when i was redoing this car i took it out on many test runs and it would easily smoke the tires in its stock form.the only egine work i did was install double roller timing chain add headers ,aluminum intake and new hei .so in theory it should run stronger .sooner or later ill figure it out and post my findings .again thanks for your input

ROCKETMAN269V

You might want to double check your cam timing. A retarded camshaft will kill your bottom end and pull like a freight train on the highway. You also didn't mention which intake you installed. Just a couple of thoughts.

deadeyejedi

Performer 350 intake ,just lined the marks up according to the manual for the timing gear set

RROLDSX

I'm thinking vacuum leak, what's your vacuum readings?

deadeyejedi

You got me on that i don't have a vac gauge I guess it's time to get one

442fanatic

Is the vac advance hooked up to the distributor when you timed? Spring combination.

Stall torque converter, medium level shift kit, lower gear. Nice to have the transmission shift and drop in rather than slush, unless you want it to be a smooth highway driver...

deadeyejedi

No , vac advance is plugged off and I did install a shift kit in the turbo 350. It shifts great but too quick imo.

ROCKETMAN269V

Hopefully you meant when you set the timing and not while you're driving. You need your vacuum advance working to get the proper spark advance when you accelerate.

Fun71

I did that once and the engine had no low end power. I later checked the cam and discovered it was 8º retarded. This is why I advocate always degreeing the cam.

deadeyejedi

Yes rehooked for the test drive .when I put the new gears in I had the number one cylinder at tdc the old gears were lined up both at twelve o'clock .then installed the new set in the exact spot . I did not degree it because I don't have a degree wheel .i suppose it's possible it could be off .

VC455

As you fill us in on details, it looks more likely that is the case.


A timing wheel and positive piston stop would be an inexpensive confirmation. And if you check that number 1 piston is on the compression stroke by looking at the distributor rotor position, you don't even have to take off a valve cover to make the check.


For about $40 you can get the wheel, piston stop, longer balancer bolt and some spacers (or just a few large nuts) to mount the wheel. Make a degree pointer out of coat hanger wire cut to a point. If you haven't done this before we can give you some help with the details.

Fun71

Something as small as the cam sprocket dowel hole drilled slightly out of spec can have a significant affect on the cam timing.

Then again, your cam timing may be OK and you have a vacuum leak as someone mentioned. You really need some diagnostic tools to do some troubleshooting to determine what the issue really is.

deadeyejedi

ill pick up the the vac guage today so that should give me some info .slowly but surely ive been picking up tools needed for proper diagnostics .

GEARMAN69

How much initial at idle ? total and at what rpm comes in ?

olds 307 and 403

What brand timing set? Some are more accurate than others. I am trying to degree my custom cam in my 350, never done it, I want to do it right. I actually swapped distributors in my 260. Kept all the good parts in the spare as my 88 may go up for sale. I had the timing way to advanced, I backed it off and this distributor has a slower advance curve. With 3.42 gears, it sounds like we have similar performance. I bought a cheap degree wheel and the Proform checker lifter, there were issues with it.

deadeyejedi

I have a cloyes set from summit racing . Initial is at 18 don't have a dial back timing light so not sure when the mechanical comes in but I've played with it 12 degrees initial to 22 and everything in between .seems to run the best between 18 and 20 .ill do the vacuum check tonight .

70sgeek

cloyes 2x roller timing sets are high quality and accurate.


I installed one straight-up on my build without a degree wheel and no discernible timing issues running essentially similar timing specs - 18 degrees initial and approx. 35-36 degrees total.


Running Flat top pistons at approx. 9.5 compression with the Howards .204/215 cam it pulls strong from idle all the way through at least 80 mph on a 3.08 posi (which is about as fast as I've pushed it to date pending further break-in).


running a 1/4" phenolic spacer between my Qjet and 2711 E-brock (essentially a stock-rise dual plane) intake and open 3" high air cleaner element as well.

deadeyejedi

ok so i did some testing tonight .initial timing at 18 degrees and judging by my homemade tape chart im getting around 16 degrees of mechanical advance .(yes the vac advanced is plugged)my new vac gauge reads 17 inches idling at 850 rpms does fluctuate ever so slighly between 17 and 18 inches. when i hit the throttle it drops immediately to 0 them bounces up to 25 then settles back in at 17in.if i tee the vac guage into the vac advance line it shows about 17 inches idiling and will decrease to about 10 inches when i throtle it up.if this all makes sense then it looks like i have to look into carburation .and just to reiterate ,this is a stock 1972 olds 350 80,000 miles with headers ,edelbrock performer intake ,and hei.thanks for sticking with me on this.

oldcutlass

What intake are you using?

deadeyejedi

edelbrock performer 350- 3711

oldcutlass

What size are the rear tires?

deadeyejedi

p245/60/r14

oldcutlass

There is the problem... Put some skinny tires on there.

Its just not going to happen with those gears unless the road is wet. You've done all you can do.

svnt442

I dunno...I had a bone stock 1975 350 in my 80 Cutlass many moons ago and that thing had a 2.28 gear in it. With 265/50/15 radial T/A's I could do a burnout from a dead stop with that car. One tire fire for a few feet at least. On freshly seal coated parking lot? .....all the way across it.

76olds

I guess you wanted to add some sealer to the inner wheel wells huh
An 80 cutlass is a little lighter than a 75 but still lol.
My 76 with a 3:42 gear and 265/60/15 radial T/A's, headers etc, couldn't pull that off unless it was just freshly sprayed haha.
Put-r-ther,
Eric

olds 307 and 403

The 2 degrees initial either way is minimal, I find 36 total the quickest at the track. What RPM does the mechanical advance all come in? How tight is your secondary air door? I find the factory setting or at least any Qjet's I have owned way to loose, means a big bog then go. As said above a leaking choke pull off also affects secondary door opening, opens too quick. Remove the hose, push in the diaphragm and hold your finger tightly on the little opening, release the diaphragm. If it moves back, replace it. Cam timing might be the issue, can be way out to lunch but try all the easy stuff first.