I have an 83 Hurst Olds in that the customer is wanting me to install a 350 SBO. The 307 has a rod knock. Otherwise a VERY nice example of a Hurst Olds. My question is will everything from the 307 including the dreaded emissions equipment swap over? He is providing a set of heads along with the 350 Olds. Is there anything in particular I need to be aware of?

 

Externally the 307 and 350 are identical. The only differences will be in the cam grind, pistons and heads. What year is the 350 and what heads are you getting?

Be aware that even though the engines are pretty close the 350 might not run well with all of the emissions equipment. Are you trying to maintain the emissions equipment to pass a smog test?

Beautiful Olds BTW!

 

The 350 is dimensionally identical to the 307 externally, so yeah, everything swaps. This assumes that the 350 heads are machined to accept the A.I.R. tubes at the exhaust ports. Use the 307 water pump to ensure the pulleys and brackets all line up. I'd also suggest using the 307 valve covers, since they are slightly smaller than those used on the 68-76 350 motors. If you plan to run the CCC system on the 350, you might need to swap out the secondary metering rods on the Qjet. If you don't plan to use the CCC system, none of that emissions equipment will even work (though if you need it to be in place for optical reasons, that's fine).

 

Thanks Joe. What is the CCC system? I assume that the air injection system?

 

Computer Command Control. The carb and distributor are computer controlled. The computer also controls the emissions equipment and the converter lockup on the 200-4R. Removing the original carb or distributor puts the system into limp-home mode and messes up a lot of the system. I suggest understanding how CCC works before disabling it.

 

Thanks Joe. Can I setup the timing (distributor) on the 350 with the CCC distributor in normal fashion with a timing light? I plan to test the new engine with everything on my test stand.

 

The distributor advance curve is only controlled by the computer. Without the computer connected, the distributor uses a default advance curve built into the module. There is no provision for a mechanical or vacuum advance - the ECU uses the TPS, distributor RPM signal, and the MAP sensor to set the timing from an advance map in the PROM. You can set initial timing conventionally, but beyond that you get the default limp-home curve (which is a minimal RPM-based advance curve, similar to a mechanical-only advance).

 

Is the ECM located in the car like my 87 GN?

 

I don't know anything about GNs but on the Olds it's in the passenger side kick panel.

 

Yep. Same. So breaking in the cam is going to be difficult on my test stand.

 

I would suggest doing break-in with a stand-alone carb and distributor.

 

Thanks Joe that's what I was thinking.

 

Joe knows a lot more than I on this subject. I swapped a 403 for a 307 and attempted to use CCC. THE 403 Had a mild Comp 252 cam. I could not get it to work and went to non CCC carb and distributor. Later to a better cam.

I believe it is possible to use CCC on a bigger engine but it almost drove me crazy.

 

Yeah I agree with him. What Q-Jet did you go with? Do you have a P/N?

 

Just keep in mind that a "stock" 350 on the CCC is just a hair better than the 307 on the CCC. You still will have the semi-restrictive exhaust and the stock timing curve, although better than a non-VIN9 Olds, it isn't built to be a screamer. You can cheat a bit and bump the base timing up a hair which may help. You could add a hypertech chip that adds a bit more aggressive timing curve, but it's no panacea.

It'll look like a stock 307 if nobody looks at the heads and block numbers, but all the dressings externally swaps over from the 307. To add to what Joe said, the water pump that came on the 83 H/O is the 556283 p/n, "long pump" - about 6" long. There was no non-air VIN 9 cars available for sale. If that's the same length pump on the 350, you're good. But if possible, swap over all the 307 brackets/pulleys, again like Joe mentioned. Likely there won't be an A.I.R. pump pulley "add on" from the 350 bottom pulley anyway. The intake manifold is the square port "flat tappet" style and works well with the 350 heads as is. I say that because all the mounting bosses, EGR port, and vacuum fittings and everything will already be in place using the old intake. For reference, 1985 (non-VIN9) and all 86-up 307s used peanut port heads and intakes when they went to roller cam. Not really what you want here. You will need to use a fuel pump that has the return line as well if the 350 doesn't have one. The H/O carb (#17083553) has no half-way open stop on the secondary air flaps like non-VIN9 cars do and with a bit better secondary rods, so that's a plus already.

I haven't researched it, but OBD1 PROMs for Olds isn't a huge profit generating business, so I'm not sure if anyone but hypertech makes any custom PROMs for it. Even when the cars were new, nobody gave two flips about burning custom maps/curves. So you're limited on CCC to what's available, which is hardly anything.

Unfortunately, if the customer wants to rip the tires off and build the heck out of the 350, the CCC will have to go. And that's going to have to be a surgical removal to do it right and not look like the 85% most of the "hack jobs" look like out there. Most shade-tree mechanics see CCC as "bad" and any wires they simply rip out without understanding what they're removing. A lot of cars ended up an early death because of the ham-handed efforts by people who didn't understand how the system functioned before ripping out wires. Plus, if you put a lumpy cam in that 350, the CCC system will stay stupid trying to "fix" itself to run, or not. Big cams + stock CCC OBD1 = Bad Idea. CCC may tolerate a little cam on the 350, but where that line is would be hard to tell.

 

We definitely aren't going to support a "Hack" job on this one. This car is way too nice. Not cutting any wires either. Not going back with a CCC. Need a suggestion and P/N on conventional Q-Jet to replace the CCC on the 350. I'm picking up a set of 350 exhaust manifolds that will work with the crossover. Also changing the distributor. Obviously the air injection lines will be gone with the conventional 350 heads, so yes an expert will be able to tell the engine has been swapped. Also need to know the proper color to paint the engine. We use KBS motor coater, and they have a Chevy Charcol gray and of course a black. Can anyone tell me which would be correct? Thanks for all of the help from everyone.

 

Black is the factory color. Hides the oil leaks.

Removing the CCC system will clean a lot of stuff up. But even a non-expert will know you've messed with it as soon as you open the hood or the throttle is pressed. Not a bad thing, but without the spaghetti, it'll become obvious.

 

Thank you sir. Just need to find an appropriate well built Q-Jet now.

 

Any thoughts on this Q-Jet as a replacement for the CCC on the 350 SBO?

 

You might call to ask how the threads on the fuel inlet are repaired since that's remanufactured. Being vacuum secondaries and an electric choke is great, but you might consider the 750 cfm carburetor.

 

G-body Olds VIN 9 carburetors are 800 CFM on a 307. At least through 1985. Not sure about the 86/87. The 800 for a 350 will do just fine as far as that goes.

Just make sure if you're retaining the 200-4R transmission that you get the TV cable end to mount properly on the carb linkage and brackets.

 

I've seen quite a few non-307 swaps but this one was done REALLY WELL and clean.

https://autocentricmedia.com/feature...ition-cutlass/

 

Barf. All is pretty much covered. Since you are removing the CCC it is much easier. If he is going with a higher compression 350 with a hotter cam, get a better exhaust, even a true dual exhaust with a factory 307 has gained a second in the 1/4 mile. The factory manifolds and the 350 manifolds are terrible but the shitty crossover into a single cat is worse. I have a full 2.5" dual exhaust with shorty headers all routed under the passenger side on my 88 Cutlass. Also a stock replacement Qjet from the mid 70's is super lean at idle so one like a Jet Stage 2 800 cfm later carb with front inlet or even better a custom one from Everyday Performance will run great and work with the 2004R, an important feature. The other carb I would use is the 750 Street Demon, the kick down stud goes in the front hole, not in the middle like the instructions show. The Qjet is more correct for this application, just needs a proper tune.

 

You know your **** 69HO43 !

69Chrgr, 69HO43 is dead on here. A run of the mill 1968-1976 350 makes about the same power as his factory VIN9

Besides my 69 I have a 1987 442 parked up in garage. She is as quick as my 69, so far.... I did just about every tweak imaginable without removing CCC. Including the Hypertech Chip.

Now will the 69s 350 in the 87 make it quicker you bet if kept raw. But not much if I am going to bog it down with all the crap that neuters the 307. Stock 87 442 comes with 170 HP, I have her showing 200 HP. Which is as good as any stock Olds 350 from 1971-1980.

If its just a basic 350, your customer may be disappointed in performance. Unless he figures an early 350 is just a better way to go which it is.


100%

That me be the trick, drop a factory built or aftermarket built big block Olds that can afford to lose a ton of horsepower and still be ballsy.

 

Thanks everyone for the input. Great information here.

 

That's why I recommend the LS or Big Block swap. Why spend all the time & money to just go back to a 200 HP engine? A 4 cylinder Toyota makes more power than that.

Either put in a 455 Olds or do an LS swap. The latter will provide better driveability and parts availability, plus it will be emission friendly.

The 307 and stock 350s were turds. Put some power under that hood like Olds wanted to but couldn't due to EPA and technological hindrances back then.

 

In response to an earlier question on what carb I used. I bought one from the old Carburetor Shop, now out of business. It later gave trouble and I replaced it with a Jet Performance Stage 2 which has worked well. That's on a 403. I do not have a wideband but wish I did.

I have had the Jet for quite a while and don't know if that's still a good choice.

 

Thanks Oldcoyote. I'll have to do more research, but the JET seems like a good choice for the 350.

 

For those saying the 350 and the 307 have the same power output, perhaps the torque ratings should be looked at as well. Torque is what gets the vehicle moving.

307 generated, what, 245 ft-lbs or so?
350 generated between 275 and 300 ft-lbs, depending upon the year.

 

And the 350 can be easily modified.

 

Exactly, people **** on the 350 for no good reason. Stock it is more reliable than any GM or any make of the same CI from that time period, period. The LS suck down low but are efficient, rev to the moon and strong but far from cheap to do right or original. Sorry, the 455 isn't as easy to build properly and live in any performance application. The big mains and heavy components need precision work and clearances or boom. Many more failures compared to Olds 350 builds. The stroker crank is a game changer, 400+ HP and 500+ ft lbs out of a 9 to 1 iron head roller cam is a nice little build and rev much easier than a 455 and only be down 20 CI. His crank is much stronger being 5140 or 4340 and lighter than the 330 crank let a lone a 455 crank. Your customer is making a good choice, do a 9+ to 1 350, at least a cam like Cutlass EFI did for me 214/214 duration along with a tuned Quadrajet and better dual exhaust, should put it about 2 seconds quicker than stock in the 1/4 mile. He already has a performance version of the 2004R with 2000+ stall converter and close to 5000 rpm shifts. He will need a torque converter lock up kit, the ECM controls it, the TCI kit works well and has an adjustable vacuum switch for a larger cam. Also a large auxiliary trans cooler and reset the TV cable with the replacement carb and use the stock bracket.

 

Interesting that the thread started off by simply swapping the 350 for the 307 keeping the emissions, and now the CCC will be gone and all bets are off. That opens up a world of modifications that can increase the performance aspects of it. Except putting in an LS. That's not cheap and IMO, a Hurst/Olds should retain an Olds engine. If the customer wants an LS, then fine. But it's never cheap.

And once it's modified, I hope the owner knows it'll never be worth what it might have been had he just rebuilt the original engine stock. Unless you get lucky and find that one dumbass who doesn't know what he's overpaying for.

And would someone please tell the owner he's got an 84 H/O front plate on that car? I'd offer $100 less for the car just for that.


Available in most repro places. Sometimes you get lucky and find a GM one. Here's the style he needs to be correct for an 83.

 

May or may not be true. Restomods have been pulling good money in recent years. In some cases pulling more than stock originals. You never know where the market will go, so unless you’re building these for a living, just build it how you want it. Hypothetical future buyers can deal with what it is.

That said, the LS swap came out of left field. Guy just wanted a (relatively) simple 350 for 307 swap. Agree with others, the Olds 350 is a pretty solid platform.

 

Sorry guys, I did not mean to ruffle feathers. The point I was trying to make was that just throwing in any basic Olds 350 is not gonna turn that Hurst Olds into a monster. Some guys think that the 307 is so weak that going to a 350 will be lights out. Maybe going from a totally stock VIN Y to a mid 70s 350 with duals would feel like night and day. But a 9 with true dual exhaust is ballsy in its own right when healthy.

While I hear what Pettrix is saying I don't agree with it. I'm proud of the way both my 307 and 350 run.

I'm not lamenting how my cars perform I'm bragging !

 

Another good reason to not go 455 or anything too potent is the garbage 7.5" rear. Is it a posi rear? The stock posi spider gears are tiny and can explode. The stock open spider gears are also soft and explode. The cheap fix on an open is Yukon spider gears, about $75. They looked perfect after multiple track runs on slicks. A Trutrac posi eliminates the spider gears and is a good design. This isn't the first 83 HO with a knocking bottom end I have seen. The 2 something gearing and constipated Vin Y 307's lasted forever. These cars rev higher and get there sooner, bye bye bottom end. Yeah, Olds really screwed these cars with the horrible exhaust. They gained 30 hp with a forced air hood, shorty headers, and a still less than ideal Y pipe into a better cat. Why GM didn't put dual exhaust on anything in those years is beyond me. The bean counters probably wouldn't allow two cats. Ford got 210 hp in 85 on their 302 HO thanks in a big part to shorty headers and true dual exhaust. Another reason modern V6 make 300+ hp is dual exhaust. Yeah, a mid 70's 350 with the stock exhaust will only be a slight improvement. My stock 73 350 in my 88 Cutlass with a custom Qjet, shorty headers and 2.5" dual exhaust, 1900 stall 2004R and 3.42 gears is fun. He should put the 307 and the factory exhaust tucked away. No one makes the H/O or 442 exhaust anymore, not a loss unless you want it factory correct. He could go Thornton Jr manifolds to look more correct, their gain without grinder work as cast is questionable. The Sanderson or Thornton shorty headers are available and should add another 10 to 15 hp and torque. The Hedman is the only affordable full length to consider.

 

olds 307 and 403, thoroughly solid advice in the above post.

Good point, slipped my mind. The only weakness to an 83 is it not having an 8.5 rear. Helps make the high performance Olds G body's pecking order easy to figure. 83 H/O peak HP, 84 H/O peak HP and rear, 85 442 peak HP, and rear, but cool and ultra valuable lightning rods are no more, 86 442 neutered engine but still a Salon, 87 442 neutered engine and only a Supreme.

LOL yes, a combo that was doing its best to resonate with the term gutless Cutlass, I've had a few. Single edge sword sort to speak. Performance so mellow it cant hurt itself or really get hurt unless its neglected. At least it embraced Oldsmobile's most important trait, reliability.

I bet !

I'm figuring our HP/TQ numbers are similar. My stock gross specs of 310HP and 390 lb ft torque convert to 250 and 330 net when dual exhaust. I'm thinking your cam and exhaust work puts you right there ? maybe a bit more ? But performance wise your gearing will wipe the floor with me. I think your 3.42 is the missing piece to my puzzle. Your trans setup is superior also but I'm not gonna be greedy for now...

My best performance as factory optioned + dual exhaust and also as currently optioned with dual's shows the same 217 HP from 1/4 mile MPH and weight. My gearing will not allow the car to accelerate significantly better. So I'm potentially leaving some 30 HP on the table. Most factory cars leave some HP on the table in all out acceleration test because very few setups are ideally efficient . But my gearing is so inadequate that the dual exhaust mod is likely not in play yet....

Proof positive that mods need to be made in conjunction with each other ? Meaning that if you option dual exhaust best to also option more aggressive gearing otherwise just a waste of money ?

I noticed the factory liked to pair the G92 package (3.42) gearing in 1971 when the 350 was dual exhaust....


P.S. sorry to veer 69Chrgr but in a sense this is all still in the wheelhouse of your threads topic.

 

This is getting to be a far cry away from slipping a 350 into a 307 slot. I guess it all started downhill when the subject of yanking the CCC reared its head. That's when the gloves came off. Or wheels came off.

Spending other people's money is a fun subject, however. Virtual wallets are always bottomless.

 

Well, it's off to the exhaust shop. I'll let you guys know how well it runs when I get it back.

 

Glad they are upgrading the exhaust. What all was done to the 350?

 

Any updates on this engine swap and build?