Howdy all-

I just purchased my first caddy. It's a 87' Fleetwood Brougham Delegance. But it has some problems. Although I've never owned one I'm sure a 307 V8 should have more than enough power to pull the boat around fairly competently.

I must be missing something.

I've cleaned the carb (the guy i got it from said he rebuilt it recently)
Changed the plugs
Changed the Cap & Rotor..

The symptoms include high gas usage, and very little power. It will run down the road pretty good at 50-65 pretty descent, but it doesnt have any getup and go. Stomp it and it doesnt accel really, and on hills it might as well not be running.. Start a hill at 70, and end up at 30 at the top (15degree incline)

As far as components it has a E4ME Quadrajoke.

Thanx - Pirg

For me I *believe* the problem is the gasline as it was replaced by a rubber tube and it's slightly bent, I'm still searching for an original replacement from the junk yard.
Aside from that, what you've said is very similar to my diagnosis. I've been able to get my girl at 140kph before nicely and above...I assume as the camaro was matching me.

Mind you, the 307 does not have much punch for a 2 ton car.

307's have no power. You have about 150hp and 240lb of Torque. I have the same engine in my buick. If you want to help add some flowmaster muffler, it helps with my 307.

And check your timing....The initial setting on these motors is around 24 degrees BTDC...And make sure the Advance is working correctly....That will also cause it to dog on acceleration...

307's have no power. You have about 150hp and 240lb of Torque. I have the same engine in my buick. If you want to help add some flowmaster muffler, it helps with my 307.

Couple things you can do.

1. Some of the later 307's that got into the Cadillacs were the Olds Cutlass 442 "307 HO" (stop laughing, please...). It was 180 hp. Check your VIN codes. Sorry, I forget how to ID them. VIN code 9 is 180HP engine, VIN Code Y is 140 hp from 1985 up. Heads, carb, cam, and exhaust manifolds make the differences. HO 442 cam is healthy. Similar to the older 1970 350 cams in specs. Like .440 lift, around 300 degrees duration.

2. The 4BBL's are restricted and calibrated lean. Modify the throttle plates to open FULLY, not OVER center. Quadrajoke or not, it still flows 800 CFM when the secondaries open fully. 800 CFM is 800 CFM! Get some richer rods from Edelbrock. How rich? Don't go too overboard, but monitor the O2 voltage at WOT, shoot for .92 to .94 volts.

3. Ensure the secondaries are opening at all. Manytimes the choke would not get to 100% open (like 95%) and the secondary lockout lever would keep them closed. 287cfm is all you get then. Make sure you get WOT when the gas pedal is pressed, not just by the linkage at the carb.

4. Get the timing set right, get a free flowing air filter (run a diesel Olds filter and aircleaner if it will fit, 14in X 5in, it should). Duct it for cold air if you can. For ever 11 degrees drop in air intake temp, is 1% HP. The stock aircleaner will strive to maintain no less that 100 degrees F. "Fix" it. I made a nice dual snorkel air cleaner for my 85 Cutlass. Looked stock, and ducted it for under the bumper ram air. Like any good Olds fan....

5. My 85 Cutlass with a 350 Olds woke up a lot with the Hooker duals for a GN Regal. Make it breathe. The more air in and out, the more power you can make.

6. Snag a 1985 Full Size Cad rear axle. Why 85? All the 4.1L V8s in 1985 were 3.42's. Towing package got 3.73's. Granted only 7.5 inchers, but as long as you don't hookup with slicks it will survive.

7. Mods.... Heads, toss em if they are 7A heads. Not junk, but not worth much for power either. Good economy. Get some early 80's 307 5A's and big valve em. Port them mildly in the pockets too. They are 64cc heads, good design. Make sure you have the CAST IRON manifolds, not the tubular stainless steel. The ports are too small and won't match up. Get a 1980-1984 Aluminum 307 intake. Flows as good as any Olds factory intake, dirt cheap, and light. And matches the ports on all other Small Block Olds. This should get you to around 200-220 hp.

307's CAN be built. Don't tell me crap about the bores are too small. Because the new LS1's are just as small. Cad 4.9's are small, 350 Pontiac's are small, etc. And they all make great power.

Need more power? Want to keep it stock? 403 baby. Toss all the 307 back on and hide the fact it is a 403.... Or a 455 and bury it more with "emissions" junk (doesn'thave to work or be hooked up, just hide the size of that engine!)

Tom Martin

The 307 v8's are bad olds engines that dont like to be in cadillacs, instead get the other engine made for that year and replace the 307 :)

Mind you our cars are from a different class. They're not race cars, and the 307 is a solid engine.

Hear Hear! Keep the 307. It really is a good engine. And keep the Quadrajet. As long as you don't care too much about milage, get some shorter rods for it, so the secondaries open a little earlier. Don't floor it either, go to about 3/4 down on the pedal, and you will get nice moving power. It's an Oldsmobile engine - it doesn't like high RPMs, and peaks out relatively low. As said above, It's a good engine, it just needs some love. Don't forget to clean the EGR passages out too. It helps. oh, and do be careful taking the carb off - don't twist the metal gas line going into the fuel filter. just made that mistake :-\

Mind you our cars are from a different class. They're not race cars, and the 307 is a solid engine.Thank you. I have never had the issues that people speak of with this engine. If I wanted a hot rod, Cadillac is not where I would look. I wanted big, lumbering, floaty, and comfortable. Bingo, I got it.

Thank you. I have never had the issues that people speak of with this engine. If I wanted a hot rod, Cadillac is not where I would look. I wanted big, lumbering, floaty, and comfortable. Bingo, I got it.


Well I have to tell you to get a cadillac without the 307, I had one with a 307 in it, I took care of it well, and the engine went with only 100k on it. I dropped a caddy 274 in it with 150k now its got about 250k on it running strong like an ox and gets up to 130mph with no problems at all. :bouncy: I also had an olds cutlass with a 307 in it, with low miles, and I had to get another engine for it. I guess as long as all the 307 owners out there are happy with their engines performance then yay for them. Peace

Well I have to tell you to get a cadillac without the 307, I had one with a 307 in it, I took care of it well, and the engine went with only 100k on it. I dropped a caddy 274 in it with 150k now its got about 250k on it running strong like an ox and gets up to 130mph with no problems at all. :bouncy: I also had an olds cutlass with a 307 in it, with low miles, and I had to get another engine for it. I guess as long as all the 307 owners out there are happy with their engines performance then yay for them. Peace
180K and still kickin' ;)

180k here too, and still purring. The 307 with the 200-r4 are still giving me excellent service. On my car...

On my Dads Estate Wagon he's at 250k on both the original engine and tranny.


Not to mention my love for 305's which are greater than the 307...whipper snapper extra parts and vacuum tubes! The 305 looks so small in comparison with all the extra doo-hickies.

307 that didn't last? What did you DO to it?! Out of all the old cars that I see, carry the 307 or 305 in them. The bodies are rusted and paint is chipping but it just won't die. I'm actually trying to find other 305,307 cars in good shape with good interiors. You can snag them for around 2000 Canadian which in my opinion, is VERY good. More reliable, great ride, just overall well built.

I would have to agree with 307 cars being durable. I certainly with (from a durability perspective) that my '85 had a 307 or SBC.

HOWEVER, I will never understand why Caddy couldn't put at least a 350 in the FWB from 1986-on. I know the CAFE thing is an issue, but couldn't they tune the front-drivers for a little less power (and more efficiency)? It's just sad when you've got a 307 that makes like 265 lb-ft (or a HT4100 that makes 200 lb-ft!) when you could have a Chevy 350, or better yet, an updated Caddy 386/425. Yes, fuel economy would be worse, but come on here, if you're buying a rear-drive Cadillac, you shouldn't be looking for economy. Buy a Chevy if you want that!

Also, is it at all cost-effective to "build" a 307? Wouldn't it be easier and less expensive to drop in a 403 or something? I guess my bias is that it's not a Cadillac-exclusive motor. Some people think engine sharing between GM divisions is a good thing; I agree, but Cadillac is a prestige brand...it should have its own "quality" stuff (versus non-quality...lol...like I said, I have the HT!)

For the 307 giving me 20mpg and the 305 giving me 22(yeah it's a chevy), I'm really happy. Although I would tolerate a 350 in a car, the power and the economy using "boat-fu". I think anything larger is getting on the show car side of things, and less practicality.

I had a 88 Brougham that didnt have any power and it was three things.

1- The catalytic convertor was started to get plugged

2- The timing was way off

3- The Torque Covertor Clutch Solenoid would stick and not let it unlock till you almost stopped.

The 307 is very reliable. In the Guiness book of world records the 307 Oldsmobile is holding the record for the most miles without a rebuild. It is a 84 Oldsmobile Tornado with 487,000 miles without a rebuild. If anybody has a problem and theirs blows up or gives out, then it was a operator problem or the engine just had a unique problem. The 307 was far more reliable than the 4100 that was in them.

Blaze

don't forget fuel and air filters, egr valve, vacuum lines, along with what everyone else has posted. But what you describe as lack of power sounds like a 307 in a 4500 lb car to me.

Mine doubled power by simply switching to 92 Octane. 135k and rolling fine, thank you...

You switched to 92 and you have noticable power differences? For an engine that does not need a higher octane I find that puzzling.

If you accelerate to 60 with higher octane and regular could you time the difference...for the sake of science! I am a Vulcan after all.

If it did it's not because of the higher anti-knock (octane) rating that's for sure.

On my 88 Brougham, the only thing high octance did for me was get rid of some light spark knocking going up hills. The owners manuals said you get the best economy if there IS a light spark knock.

Blaze

The 307 should have enough power to move the vehicle better than it sounds like it's doing. However, you might want to check the catalytic converter. If it is plugged it can really rob power from any engine, because of the inablity to back pressure all of the exhaust gas from the head, thus contaminating the air -fuel mixture and really decreasing performance. I had an '85 Pontiac Parisienne (no it wasn't my grandma's, it was someone else's) with a 305 and a few months after I bought it, I had the same type of problem you're describing. It got to such a bad point it would stall out going up very steep hills. It was a simple fix and it really improved things. I dunno, just a thought.

Brian

I think my timing advance is broken on mine. I had the light on it and rev'd the motor, but the timing stayed exactly the same. What controls the timing on 307 olds? I thought it'd have an HEI with vacuum advance, but it doesn't.

are you trying to set the timing on your car? if yes did you jumper the connections under the cig lighter? If yes when you started the car after jumping the connections did you see the chk engine light flash? Do you know what vacum lines to plug up in setting the timing as well?

Yup, trying to set the timing per the VECI label. I have a GM diag tool, so I plugged that into the OBD plug under the center dash (which should ground out the diag stuff). I plugged the small vacuum line that ran into the air cleaner from that T-fitting. No matter what RPM I was at, the timing stayed the same.

Couple things you can do.

1. Some of the later 307's that got into the Cadillacs were the Olds Cutlass 442 "307 HO" (stop laughing, please...). It was 180 hp. Check your VIN codes. Sorry, I forget how to ID them. VIN code 9 is 180HP engine, VIN Code Y is 140 hp from 1985 up. Heads, carb, cam, and exhaust manifolds make the differences. HO 442 cam is healthy. Similar to the older 1970 350 cams in specs. Like .440 lift, around 300 degrees duration.

2. The 4BBL's are restricted and calibrated lean. Modify the throttle plates to open FULLY, not OVER center. Quadrajoke or not, it still flows 800 CFM when the secondaries open fully. 800 CFM is 800 CFM! Get some richer rods from Edelbrock. How rich? Don't go too overboard, but monitor the O2 voltage at WOT, shoot for .92 to .94 volts.

3. Ensure the secondaries are opening at all. Manytimes the choke would not get to 100% open (like 95%) and the secondary lockout lever would keep them closed. 287cfm is all you get then. Make sure you get WOT when the gas pedal is pressed, not just by the linkage at the carb.

4. Get the timing set right, get a free flowing air filter (run a diesel Olds filter and aircleaner if it will fit, 14in X 5in, it should). Duct it for cold air if you can. For ever 11 degrees drop in air intake temp, is 1% HP. The stock aircleaner will strive to maintain no less that 100 degrees F. "Fix" it. I made a nice dual snorkel air cleaner for my 85 Cutlass. Looked stock, and ducted it for under the bumper ram air. Like any good Olds fan....

5. My 85 Cutlass with a 350 Olds woke up a lot with the Hooker duals for a GN Regal. Make it breathe. The more air in and out, the more power you can make.

6. Snag a 1985 Full Size Cad rear axle. Why 85? All the 4.1L V8s in 1985 were 3.42's. Towing package got 3.73's. Granted only 7.5 inchers, but as long as you don't hookup with slicks it will survive.

7. Mods.... Heads, toss em if they are 7A heads. Not junk, but not worth much for power either. Good economy. Get some early 80's 307 5A's and big valve em. Port them mildly in the pockets too. They are 64cc heads, good design. Make sure you have the CAST IRON manifolds, not the tubular stainless steel. The ports are too small and won't match up. Get a 1980-1984 Aluminum 307 intake. Flows as good as any Olds factory intake, dirt cheap, and light. And matches the ports on all other Small Block Olds. This should get you to around 200-220 hp.

307's CAN be built. Don't tell me crap about the bores are too small. Because the new LS1's are just as small. Cad 4.9's are small, 350 Pontiac's are small, etc. And they all make great power.

Need more power? Want to keep it stock? 403 baby. Toss all the 307 back on and hide the fact it is a 403.... Or a 455 and bury it more with "emissions" junk (doesn'thave to work or be hooked up, just hide the size of that engine!)

Tom Martin



So what's all this gonna cost me? LOL Parts in at least the hundreds? Labor is around $70/hr and I'm guessing it's SEVERAL hours of work. =P Anyone care to ballpark something like what is described above?

Hard to say what the cost would be, as I do all my own work.

You can sang a set of 81-85 5A heads from a boneyard for $50 or less. They are the smallest chambers since 1971, 64 cc if I recall. They work fine on a 350 or 403. But just small valves. The 403 has larger, but larger chambers. The 455 has best, and they will bolt on a 307, but the runners are getting big too, so velocity is lower.

Key thing that people don't understand. It isn't FLOW per se, it is velocity. The 7A heads do have good velocity, but the ports so so small, they peter out above 3500 rpm. So below 3500, they are great. Drop them on a 350, and it will down to 3000 rpm, 403, likey around 2500 and it will run out of breath, but it will have torque like a BB until that.

If it was me? Cost an issue? Most bang for the buck? 350 Olds are cheap and plentiful still. The ECM won't know what displacement is there. Get one, bump up compression to around 9:1, you can do this by taking the 67 cc 350 heads and shaving 0.060 off and according to Mondello this will get you close to 9:1. Get a cam in the 194/204 range, .450 lift, 111 lobe sep or less. Don't go too nutty here, it will kill emissions. Honestly, pattern the LT1 cam for the B/D bodies, it is a good one. This will bolster low end torque, which is what you need. If you run flat top pistons (not common) you don't need to shave the heads, if you run off the shelf cast (keeps costs down, and they are very reliable to 5500 rpm) shave.

If you have cast manifolds, leave them alone. Go to a Detroit Diesel dealer and get the passenger side exhaust manifold plug and run the crossover out and make dual exhaust. GM Sold the 5.7L Diesel stuff to Detroit Diesel.

Get a 1981-1984 Olds 307 intake, this will match the 1984 and older Olds heads, and is a good design. The Edelbrock Performer should also be acceptable. Do not mess with a Performer RPM. This will murder low end. Velocity is the name of the game.

Paint the intake black, run factory valve covers and no one will be wise to a non 307 being in there!

350 Blocks: 1977 up and up most if not all were "windowed", these are not suitable for high rpm use, but are significantly lighter than the 1976 and older non windowed. The non Windowed can see much higher rpm. ALL 403's are windowed. There is no legitimate documentation yet to prove outside of GM Engineering that the non windowed 403's ever exist. Don't waste the time looking....

The 400/425/455 will be great in there too, but at the expense of lunching the trans if you punch it. The power exceeds the 200 4R in stock forms power rating. You can do it, but be careful, that one time you smack that kid in the ricer you may be getting towed home.... And front springs will need replacing for the additional weight. So handling will be worse too. With todays gas prices, it may not be worth it.

Of the BB's the 455 is cheapest to rebuild, but still expensive. Of the SBs the 350 is cheapest. 307's can be expensive mainly due to pistons, they aren't common size. 350 Olds are 4.057 bore. Creative people can fit a Chevy 0.060 over piston in there with the 6.0" Chevy rod with some crank machining. This can be cost effective if you are going high rpm. Racers used to take Olds 350 rods and put them in SB Chevies before low cost Chevy 6.0 rods were available.

Expect to spend $1000 on a GOOD rebuild of a 350, and more like $1500 on a 455. Not including the cost of the engine. I got a good runner for $300, that is still in my Cutlass today (sold it, but I still see it around). I had to put a cam in it. Never ever let a non roller cam Olds have a weak timing chain, they eat cam and distributor gears when they get loose! The cam walks around in the block and the distributor gear is what tries to keep the cam in place. Eventally it lunches and leaves metal filings all over. Roller cams (All 307's with 7A heads, 1985-up) do not have this issue as they have a cam holddown plate like a Pontiac or a Chevy V8.

Wow, thanks! My mechanic says he put in a 350 in someone's Brougham recently and it made a small difference but not worthwhile unless you need a new engine. He's probably right, since I paid $3500 for the car...and it'd cost me around that for the swap. I'd be better off buying a second car, perhaps. I sure love how the Caddy feels on the highway, though--except for havng to floor the thing to keep up with traffic. =P I'll keep it in mind and thanks again, it's really good info.

Hey,

I have a 403 with 69'#5 350 heads, a mild cam, performer intake, modified Q-Jet, and no computer. The 200r4 got a rebuild and a very mild shift kit, and I picked up the 3.42:1 rear out of a 4100 car. Dual exhaust and this car really moves, supprises the hell out of people. I even passed emissions like this(not shure how, had to be the dual cats). If you want some real power and still a nice driving caddy this is the wany to go.

Hope this helps someone.

Kevin

Alright, I was suffering the same problem. My fuel curve was WAY off, so I actually pulled the carb and rebuilt it. Follow the rebuild kit's directions on setting the idle screws and pilots. That'll gain you some power. My big power gain was doing the timing. Jump the connector under the dash and then set the timing to 20 degrees advanced. The car will get up and go to 60mph no problem then.

Hey,

I have a 403 with 69'#5 350 heads, a mild cam, performer intake, modified Q-Jet, and no computer. The 200r4 got a rebuild and a very mild shift kit, and I picked up the 3.42:1 rear out of a 4100 car. Dual exhaust and this car really moves, supprises the hell out of people. I even passed emissions like this(not shure how, had to be the dual cats). If you want some real power and still a nice driving caddy this is the wany to go.

Hope this helps someone.

Kevin

Does your 2004R shift properly under full throttle? If so which shift kit did you use. I had 2 different ones behind a 500 over the years and could never get one to shift well under full power. Also how is your fuel economy on the highway? Thanks.

Hmmm... The Cadillac in my care has the good ol 307 in it and it feels like more than 140hp to me. The Caddy has more metal than the average car, explaining the 5572lb curb weight. Mine shifts through the gears pretty quick and can feel sluggish at times, but the upshifting is smoother than butter on hills if it starts losing speed. I personally drive a 1993 Ranger Splash with a 4-cylinder in it with 8 spark plugs. Mazda engine. It supposedly puts out just over 100hp and it only weighs about 3,000 pounds. It isn't nearly as fast on exit ramps as the Cadillac. Highway speeds are a breeze in the car while I have to floor it and PRAY to get up to 70mph in the truck.

The 307 was excellent for torque. Compare other 5.0L engines from Ferd, Chubby and Dodgy. The 307 Olds had the best torque. Keep in mind, compare carb to carb, and year to year. 255 lb/ft at a farily low rpm. Like around 2200 rpm. Not too many engines in a 5L size make that much torque at that low rpm. The small runner 7A heads were a major contributor to that.

The 307 was one of GM's firsts to be a roller cam engine thanks to developement on the 350 Diesel in the early 80's. Yes, something good DID come of the 350 Diesel!!! Granted, they are heavy lifters and not suited for performance, GM did learn a lot.

Best thing you can do is step up to the big time five hundred. It will take a pretty extensive buildup to get a 307 300hp, that's almost to 1hp per ci. A stock 500 puts out that power level, plus an extra 200 plus ft.lbs. of torque. Buy a good running 500 and TH400 from a rusted out 70s car and swap it in for way under a grand.

Then if you have a bit of extra cash and want more power, buy a cam, modify the stock intake manifold, run headers, swap in rear that won't grenade, then stick a 200 shot of nitrous and you have a Cadillac that should be able to take an E55 AMG for around $2000.

That's great for people who can do the work themselves...but the rest of us can't pony up the labor costs. An engine swap, not considering the cost of the engine, costs around $2,400. Swapping the tranny adds another grand. Buying a tranny from a junker and hoping it's in good enough condition w/o a rebuild to operate smoothly and faithfully is too big a risk to take and not worth it, IMHO. So by the time you buy the engine, the transmission and pay for labor, you're up around $5,000. Several of you on here can probably do the work and undoubtedly have. Unfortunately, those of us who really want to "upgrade" probably can't. =P In the end, it's probably cheaper for me to beef up what I have, including the tranny.

If anyone knows how I can swap in a 500 CID and the TH400 for less without doing the work myself, let me know! *DROOLS* Honestly, I think that's too much gasoline for my taste. I'm already spending $50/week. =P