golow1

Looking for some minor changes to free up more HP without touching the engine. Exhaust Mods? It has the original exhaust system. How much more HP would result? Thanks in advance

golow1

I have an 83 Hurst-
Looking for some minor changes to free up more HP without touching the engine. Exhaust Mods? It has the original exhaust system. How much more HP would result? Thanks in advance

billmerbach

Put an electric fan on it it'll add I believe 20 more HP

joe_padavano

As compared to the stock clutch fan? Not even close. 0.5 HP downhill with a tailwind, MAYBE. You'll get more of a HP boost with a coffee can exhaust tip.

Look, the 307 is not the best place to start for HP. Number one is to be sure the CCC system is operating properly. Beyond that, headers and a lower restriction exhaust are your best bets. Just don't expect any miracles. The only way to seriously increase HP in that car is to jack up the air cleaner and drive a 350, 403, or 455 under it.

billmerbach

My bad joe I've heard and read that places sounded weird to me as well can't trust the internet I guess lol

joe_padavano

To the OP, I merged your two identical posts. You'll typically get better quality responses if you stick to a single thread rather than splitting the responses among multiple threads with the same question.

Kennybill

Nitrous. Find the weakest link.

83hurstguy

more gear, more converter, true dual exhaust, cold air intakes, dialed in CCC system (ensure EVERYTHING is tip top shape and understand how to tune)... you may see bottom 15's.

Motor really needs more cam and compression to do anything.

cutlassefi

It's gonna be like getting blood from a rock.

need4speed

I had an 83 Hurst Olds back in the late 90s. There is not a lot you can do to get more performance out of it. It is a small, smoged poor excuse for a V8. My advice, other than an engine swap, would be to put steeper gears in the rear. A Monte Carlo SS rear will bolt right in, and has 3.73s. You will get a little out of headers, but like has been written here, don't expect too much.

88hurstolds

Not much you can do with 307s, they function best on the computer as they were designed with all the emissions equipment.
Best thing you can do is free up weight and make sure everything is in good working order.
Exhaust will help some too but if you go beyond that you are just going to have to go another route all together with a 350 or 403 or 455.
What every mods you make be sure to SAVE all the original equipment.
These cars are always hacked up and many are missing the numbers matching components which make them collectable and valuable.
An original numbers matching non boogered up '83 Hurst is sometimes worth double of that with one with a 455.
If you go that far sell the Hurst and clone a Calais and pop a 455 in it.
Here's a good start:

http://realoldspower.prophpbb.com/topic1244.html

golow1

Thanks-

88hurst, the car is all original. Would changing out exhausts hurt the originality?

olds 307 and 403

The original exhaust would only count on a points car show. The best headers are by far the American Racing headers but cost $1000. Either Sanderson or Hedman ceramic coated are really your only other considerations. Go either 2.25 or 2.5" mandrel bent duals. You also need an O2 bung welded in the passenger pipe and your car already has 3.73 gears.

455man

Here's a link for some tips.
http://performanceolds307.tripod.com/