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Motor Going..going..not gone yet but soon im sure..

3K views 14 replies 5 participants last post by  RobDeville 
#1 ·
My 307 is on its last legs.. could be months maybe weeks and im looking to replace it. This is a 88 FWB.

So I have a few questions.

1. What other engines could i put in my baby and still be legal.. like as in pass smog and such. the stock 140hp just seems weak.

2. What would be a fair charge for a motor swap? ive been quoted 3.5k

3. What should be included in the cost? Heads? oil pump?

4. What should I have done at the same time if its not included?
 
#2 ·
How many miles? You might want to do a little tranny work now if you've been having any problems. Unfortunately out in Sacramento you're fighting the smog Nazis, so honestly, getting away with too much will be difficult, however, the Olds 403 is identical to the 307 on the outside. I'm sure N0DIH will post more, he knows alot more about Olds engines than I do.
 
#4 · (Edited)
Olds 350 has best support, they made a LOT more of them than the 403. The 403 is a decent engine, get one if you can, by all means, CID is CID. When it comes time to rebuild, the 350 is cheapest.

You'll have to check local laws on swaps. Some allow different familes as long as it was factory there (like many cars got a 3.8L V6 and an optional 307, so either is ok) or some allow only same familiy engine (307 stock, so an Olds 260, 330, 350, 403 are all ok to swap in, 400/400/425/455 might be if you are sneaky or they are lenient.... Or in some cases same family, but same year or newer is required. In some cases anything goes as long as you can make it pass smog tests.

Olds 307's might still be available through GM, last price I saw was $1500-$2500 for a NEW GM engine. Install isn't too hard.

Want 250 hp and cheap? Get a Chevy 350 crate engine short block and a set of Vortec heads with a stock B/D LT1 cam. You can do that all for around $1500. IF you don't care about originality or original looking engine looks.

OR, if you can get away with it, a Cad 500 is tough to beat!

Now, you might ask, what might I do?

Well glad you asked!
I would go to car-part.com, and order a 5.3L V8 ($500-$800), order a 4L65E ($600), PCM and wiring harnesses ($50-$100) and spend the time to make it all work. Then you get a solid 300hp with great mpg and power, and an modern drivetrain.

But then again, that is me. On my Cad, originality isn't too important on the drivetrain, on my 80 Turbo T/A, being all Pontiac is, but not necessarily original engine (I have anyway)
 
#5 ·
The thought of 250+ horsepower in my baby brings a tear to my eye. the 350 option probably is my best option but finding a shop to do a swap like that may be hard to find. My regular mechanic is great but seemed kinda put off when i suggested a upgrade to the engine rather a straight swap. I'm a complete noob to mechanics.. I can do my own oil changes though..

I have no issues paying to have it done. here is another question.. will my existing tranny work with a 350 and can it handle the extra power? and yes the tranny if it is compatable will get a full service and have the tcc replaced.

is putting a 5.3 in there legal? I still have a few years before i get to avoid the dreaded Smog Nazis.. so untill then it has to be legal.. once the day comes that I dont have to worry about it .. all I can say is vroom..
 
#6 ·
In any state that has emissions inspections, it is technically illegal to swap in an older model year engine. Since the only Olds motor being built in 1988 was the 307, that's all you can legally install there.

Now, having said that, all Olds small blocks (260, 307, 330, 350, and 403) are externally identical. You can install a 350 or 403, dress it to look like the 307, and almost certainly pass any underhood visual inspection. You will need to retain the electronic Qjet carb, but that's not really a problem. The EQjet only controls the primary side. The secondaries work the same as any other Qjet. This makes it pretty easy to rejet the secondaries for the larger displacement. You will need to rework the stop on the air valve so it opens fully, but that's a simple task with a file. If you feel lucky (and depending on the skill of your local inspection station), you can try to install an Olds 455. The Olds big and small blocks differ externally only in deck height, so to the untrained eye, they look the same if you don't have one right next to the other to compare. Members on the Olds email list have made the EQjet work very well with a 455. Note, however, that anything with more torque than the 307 will probably shred an unmodified 200-4R transmission in short order, so expect to get a beefed up trans as well.
 
#8 ·
If you can't or don't want to do the work yourself, that's probably not too far from the cost. A normal repair shop will pretty much only want to do a direct replacement. ATK Engines offers a rebuilt 307 long block for $1750 plus shipping and core charge. You might be able to find a different supplier for less. Add to this the labor costs from the shop, new motor mounts, belts, hoses, filters, coolant, oil, spark plugs, etc., and you're probably in the $4K-up range.

Any sort of engine swap will require some head scratching and custom work, with will probably require a custom shop. Expect to pay by the hour for whatever it takes.
 
#9 ·
Go find an Olds 350, they are cheapest to rebuild of all Olds, rebuild it, toss on the Olds 307 heads (higher compression, will boost some efficiency, but won't flow well over 4000 rpm), perfer to be rebuilt while you are at it, and drop it back in. You can do it easily for $2K. EASILY. If not less if you watch yourself. Paying someone, that is another story.... don't tell the SMOG cops, they likely will never know. Get a stock type cam for the 350, like the 1980 grind, that was last for the 350, would be best emissions. AVOID the 204/214 duration cams (SSI has it cheap @ PAW), you will never pass emissions with it, I had one, that one sucked for smog, compression is still to low to make it work well. A 83-84 HO/85-87 442 cam is best, and should do well in the 350.

Remember, you aren't racing. You don't need high $$. How long are you keeping it? Forever? 1 year?

That is how I would do it. Retain all the 307 smog junk, and put it all back on the 350. It will behave well.

Locally they were selling Olds 307's for $125 in the boneyard running good and guaranteed for 30 days.
 
#11 ·
Find a new mechanic. He is RIPPING you off bad.
 
#12 ·
Certainly get more than one quote, but I'm curious why you say that. First, figure out what's included in $3500. The shop will always put a markup on the parts, so my retail price of $1750 for a rebuilt 307 long block is probably comparable to what's in this quote. Now the shop needs to disconnect everything, pull the motor, swap flywheel, starter, water pump, intake, exhaust manifolds, distributor, balancer, hoses, emissions equipment, brackets, accessories, etc. I'm sure they've also assumed at least some of the exhaust bolts will break and need to be drilled out. 307s are also notorious for the A.I.R. tubes rusting out, so the cost of new tubes is probably in there. A good shop will include new hoses and filters, plus there's the cost of oil and coolant (have you priced motor oil lately?). Frankly, if I were doing this myself, I'd also put in a rebuilt starter and water pump at this time, but that's me. What's the going rate for shop labor - $75 an hour? (I do all my own work, so I have no idea) Even 20 hours at that rate is $1500 labor. Add the hoses, filters, fluids, contingency, and sales tax, and you're rapidly at $3500.
 
#13 ·
Honestly, sell the car as is, get what you can. I picked up my 94 Fleetwood LT1 with RPO V4P (tow package) for $3800. I have seen them as low as $2500, and a Roadmaster recently for $1250.

I do my own work (obvious reasons why!), and I still can't bite anyone charging that much just to R&R an engine. It isn't like it is a FWD car that is a pain. $1750 is steep for a rebuilt 307. That better be a high end rebuild, ported heads and all. Nothing less for that price.

It will always be an older car. If it means that much to you, and you have that sorta $$ to spend, fine, no problems. But honestly it is quite inflated prices. Shop around, dig up other alternatives. Find out what the engine swapping laws are in Cali. You might be much better off getting a more modern engine (LS1 with 4L65E, you can get for $1500 for the PAIR!) and drop it in. THEN and only then it is worth $1500 to pay someone to install for you.
 
#14 ·
Honestly, sell the car as is, get what you can. I picked up my 94 Fleetwood LT1 with RPO V4P (tow package) for $3800. I have seen them as low as $2500, and a Roadmaster recently for $1250.
Look, I'm not arguing that it's more money than the car's worth. On the other hand, every example you've sited has a USED engine with some number of miles on it that may or may not need work in the near future. You can't exactly compare that to a brand new engine. Is the used car a better value? Sure, almost always.

I do my own work (obvious reasons why!), and I still can't bite anyone charging that much just to R&R an engine.
So you think you can completely R&R that particular engine, with all the accessories, emissions equipment, likely rusted fasteners, etc, in less than 20 hours? Including tuning the new engine, break in, etc? With enough confidence in the work that you'll also provide the customer with a warrantee? All I know is that having worked on my own 86 307, I wouldn't sign up to that. It took me a couple of evenings just to pull and replace the exhaust, since I had to torch off a couple of the manifold bolts, pull the pass side manifold (which means pulling the oil filter adapter), heat and remove the two broken bolts, install helicoils, reinstall the manifold, repair the busted EFE on the other side, and finally put it all back together, install the new O2 sensor through the gap between the inner fender and frame, fire it up, then pull it apart again because the parts house gave me the wrong exhaust gaskets and they didn't seal properly (307s have smaller exhaust ports than any other Olds V8).

It isn't like it is a FWD car that is a pain. $1750 is steep for a rebuilt 307. That better be a high end rebuild, ported heads and all. Nothing less for that price.
Apparently you haven't priced stock rebuilt long blocks lately - or custom built engines (try $7k - $10K). Keep in mind that the much higher volume of SBCs keeps their price lower. Also, as I noted I only checked one source (ATK Engines) that I've had good luck with in the past, though mainly on modern 4 cyl motors. I'd certainly do my own rebuild on an Olds V8. Of course, I also have all the tools, hoist, manuals, experience, etc. to do the work. There's a cost associated with all that as well.

It will always be an older car. If it means that much to you, and you have that sorta $$ to spend, fine, no problems. But honestly it is quite inflated prices. Shop around, dig up other alternatives. Find out what the engine swapping laws are in Cali. You might be much better off getting a more modern engine (LS1 with 4L65E, you can get for $1500 for the PAIR!) and drop it in. THEN and only then it is worth $1500 to pay someone to install for you.
And those prices are for freshly rebuilt engine and trans? Of course not. And naturally, $1500 doesn't cover the cost of the computer, wiring harness, electric fuel pump, different exhaust system, different hoses, different throttle linkage, different motor mounts, different driveshaft, different trans crossmember, etc, etc. Yeah, that's MUCH less expensive.
 
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