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Welcome any input.... I have a '67 327/300hp all factory. Not really considering doing anything internal , but have been thinking about doing two things only.....1) installing a cold air filter just to juice it up a little and 2) maybe replace the radiator with a aluminum dual electric fan configuration. Rresearch says I should get about 10-15 more hp from the cold air filter and maybe another 5-10 max hp from the radiator. Don't desire to do any other modifications. Welcome the input from you guys/gals that know much more about this than me. Thanks. Dave
I wouldn't start putting Hot Rod Harry do-dads on an original car to get MAYBE a 20 hp increase, MAYBE. The hype for aftermarket 'performance increases' is usually just that -- hype. Your 300hp car will never be an asphalt-eating beast. Relax and enjoy what you have...
Those additions will prob not even register in a 'seat-of-the-pants' boost in performance.
I wouldn't start putting Hot Rod Harry do-dads on an original car to get MAYBE a 20 hp increase, MAYBE. The hype for aftermarket 'performance increases' is usually just that -- hype. Your 300hp car will never be an asphalt-eating beast. Relax and enjoy what you have...
Those additions will prob not even register in a 'seat-of-the-pants' boost in performance.
Thanks Frankie.... Your advice is well put... I guess I was thinking that running cooler and cooler air is more engine efficient and the added hp was a nice benefit as well. Thanks.
What condition is your old radiator in now? A new Dewitt factory replacment with a working fan clutch is all you need if you feel like spending a grand
Thanks Frankie.... Your advice is well put... I guess I was thinking that running cooler and cooler air is more engine efficient and the added hp was a nice benefit as well. Thanks.
Your way of thinking is absolutely correct. Cooler air going into the engine is better for the engine in regards to performance. No one can dispute this due to about every car made today and for a good long while has the air going into the engine coming form a source that is in front of the radiator or off to the side of it so the air is NOT being heated......but what Frankie mentioned is also 100% correct also.
You would not feel 20 HP gain my any stretch of the imagination. And what 'they' do not tell you is where in the RPM range does this increase show up. I get customers who want 'hop-up' their car and the first thing I tell them is that we need to go to the chassis dyno shop and see what they have for horsepower and torque...and then when they have spent a little bit of money or buckets full of cash. We dyno the car again so they can actually see the improvement.
What condition is your old radiator in now? A new Dewitt factory replacment with a working fan clutch is all you need if you feel like spending a grand
Appears to be in fine condition.
No need really to do anything presently. Just sort of looking at options. Thanks !
Your way of thinking is absolutely correct. Cooler air going into the engine is better for the engine in regards to performance. No one can dispute this due to about every car made today and for a good long while has the air going into the engine coming form a source that is in front of the radiator or off to the side of it so the air is NOT being heated......but what Frankie mentioned is also 100% correct also.
You would not feel 20 HP gain my any stretch of the imagination. And what 'they' do not tell you is where in the RPM range does this increase show up. I get customers who want 'hop-up' their car and the first thing I tell them is that we need to go to the chassis dyno shop and see what they have for horsepower and torque...and then when they have spent a little bit of money or buckets full of cash. We dyno the car again so they can actually see the improvement.
DUB
Thanks Dub.... Like the efficiency part but if you say I'll never notice the hp gain I'm leaning against doing now. Thanks.
Shakesd67,
Welcome to the forum! Mods are a very subjective and personal thing and you’ll get as many opinions as answers.
Here’s mine: you can’t go wrong with a DeWitts radiator and fan. I have one in my 66 with a GMPP 385HP motor and IMHO you can never have too much radiator (search for my Epic Build thread). As for other mechanical upgrades, have at it and post pics.
Enjoy your car the way YOU want.
Those advertised HP “gains” are usually both theoretical in nature and, even if ever actually realized at all, happen only at the upper end of the rpm range. The question thus becomes - how much time do you spend at peak rpm and/or ripping thru the gears up to redline?
With the 327300 engine your car is designed to get its performance primarily from its torque, not peak rpm.
A good tune up with the carb, distributor, jetting, and advance curve being optimized would likely be the best investment you could make.
Last edited by tuxnharley; 04-22-2018 at 09:27 PM.
Reason: Typo
Spending $800-$1000 for a DeWitt radiator/ fan setup for a 5 hp bump you won’t even feel ?
Somebody tell me how that makes any sense.
If the OP wants to spend several hundred bucks on a slick mod then buy the Detroit Speed electronic headlight motor conversion or get a solid state radio with Bluetooth. Now those will make a difference in driving pleasure.
Last edited by Frankie the Fink; 04-22-2018 at 11:26 PM.
If you want a cold air intake, get a BB hood made for it or modify it. That's what I did.
The fiberglass insert was removed, the back ground out, and reinstalled. Similarly, I used the belt sander to remove the "closed black area" leaving only the chrome for the trim to trim out the hole. Finally, a 327 logo was added so no one would think it's a "poser."
Those advertised HP “gains” are usually both theoretical in nature and, even if ever actually realized at all, happen only at the upper end of the rpm range. The question thus becomes - how much time do you spend at peak rpm and/or ripping thru the gears up to redline?
With the 327300 engine your car is designed to get its performance primarily from its torque, not peak rpm.
A good tune up with the carb, distributor, jetting, and advance curve being optimized would likely be the best investment you could make.
Thanks all for the helpful input..... really made a difference in my thinking especially if I'm not going to really notice anything.... and, I just stay in the "right lane" now anyway haha
Shakesd67,
Welcome to the forum! Mods are a very subjective and personal thing and you’ll get as many opinions as answers.
Here’s mine: you can’t go wrong with a DeWitts radiator and fan. I have one in my 66 with a GMPP 385HP motor and IMHO you can never have too much radiator (search for my Epic Build thread). As for other mechanical upgrades, have at it and post pics.
Enjoy your car the way YOU want.
Best of luck, welcome and post pics!
Matt: Thanks. Appreciate your input. And, Semper Fi my man! 1302 !
04-22-2018, 05:36 PM
Cold Air Intake
