at3reg98

I have a chance to buy a 62k mile Hurst 307 for $300 and was considering swapping it in place of the regular 307 in my '83. Thought that would be neat in a Olds 98 to make it look stock. My motor has 146k on it and thought it'd buy me some time.

Is it worth the swap or should I just find a 350 and put that in down the road? Also, I imagine I'd need the computer from the Hurst car correct? Not sure what the differences are.

Lady72nRob71

The regular 307 has 140hp and the HO307 has 180hp. A 68-72 350 can have around 200hp+ stock (depending on year, carb, exh, etc) with lots of opportunities for economical upgrade. I would go for the latter if possible. The stock 307 computer will behave with the 350 and keep you 'legal' if you use the 307 carb and disty... Would look stock when painted black.
If 180 is good enough for you, then that 307 will work. But to get the most out of it, you will need the ho computer, as the timing curve is different, as well as A/C control.

ThePackRat

Adding to the above .....

The cam - carb & harmonic balancer were the main differences in the actual motor's themselves in a VIN Y vs a VIN 9 car.

However, that is only part of the equation on these.

IMHO ...

It was the higher stall torque converter & the 3.73 gears out back that made the most significant difference in real world performance.

The Y-pipe dual outlet exhaust of the VIN 9 did help some as well in my own real world experiences.

In regards to keeping the current VIN Y in your 98 vs swapping it out for the VIN 9 motor :

Naturally a 350 or bigger would always be the better choice as already mentioned.

Of course' the more power you put under the hood ... the faster the stock trans behind it will take a dump.

Before going any further on this subject :

Will you be wrenching on it yourself ... or would you need to pay someone to do the work for you ?.

I think the answer to that will determine what the best course of action is at this point.

ThePackRat

Oh yea forgot to mention above .....

The VIN 9 G-Bodies had a dual snorkel air cleaner as well.

at3reg98

Hmm.. if it's only 40hp and considering I only have stock rear gears and exhaust it doesn't sound like it's worth the trouble. Guess I'll just look for a good 350. Sounds like the 307 was another one of GM's motors to meet CAFE requirements.. I've heard the same regarding the sbc 305. Thanks for the info- still new to the Olds circle.

Lady72nRob71

It was mainly out of tightening emission requirements. From what I have heard, the adding of all that emission crap actually killed down the mpg a bit...