[STL. Mark]

I am not sure if this is the right place to ask my rather dumb question. My 1969 mustang 302 two-barrel engine, single exhaust was rated at 210HP. Over the years I have converted it to dual exhaust with Headman long to headers, aluminum four-barrel intake with a Holly 600 carburetor. I know there are a lot of knowledgeable folks on this website so any idea on approximate horsepower? Thanks.

 

[pprince]

~190 hp at the rear wheel with a manual tranny and manual steering.

30 less is you have an automatic and power steering.

 

[Nitmare67]

You might have picked up a maximum of 25hp over the stock rating. Headers can be a great bolt on but the hp increase is going to be alot smaller on a factory 302 compared to something with performance heads and cam. If you really wanted to wake that motor up I would recommend changing the camshaft at a mimimum. Just moving to a camshaft around 218 @.050 would really wake that motor up. Add a set of 170-190 CC aluminum heads with a mild cam and it could pick up easily north of 70hp.

 

[Woodchuck]

My approximation would be 225 gross HP but at a higher rpm than the stock HP peak. The bigger question is what did those changes do to the TORQUE curve..... TORQUE is the force you feel in the seat of your pants. HORSEPOWER is how long you feel it.

 

[rose62]

Much of the difference between HP numbers of the late 60's vs early 70's cars (besides the near universal compression ratio drop) was a result of a change in rating methods, gross vs net. So, rated a few years later and your rating would have been around, what, 155? Do you know the compression ratio of your engine?

 

[Woodchuck]

Do you know the compression ratio of your engine?

1969 302-2V was "advertised" 9.5:1 but actual was closer to 8.8:1.

 

[wicked93gs]

Don't waste time guessing. If you really want to know take it to a dyno. The question isn't how much power it makes, but whether it makes enough power to do what you need it to do.

 

[JohnnyK]

How accurate is a standalone 'module' like a G-Tech Pro? (According to reviews at least, pretty accurate. Is it more accurate than a modern cell phone? Are G-Tech's still rocking 20 year old technology?

 

[rose62]

1969 302-2V was "advertised" 9.5:1 but actual was closer to 8.8:1.

This has always puzzled me: why do (did?) manufacturers put out inaccurate info about c/r? They wouldn't say a crank journal was 3" if it was actually 3.125. I can't imagine the casting tolerances were that loose.

 

[macstang]

How accurate is a standalone 'module' like a G-Tech Pro? (According to reviews at least, pretty accurate. Is it more accurate than a modern cell phone? Are G-Tech's still rocking 20 year old technology?

I got the Dragy and I like it. The software is a cellphone app for Android and Apple and it was pretty buggy at first but they put out a revision and it has cleaned up a lot. So far I've run my truck, my best friend's 350Z and his son's GTI with it. I have not run my car on it as of yet. Be aware if you post yourself doing illegal things on the street online with Dragy evidence that the police may come and visit you.

 

[66coupe289]

How accurate is a standalone 'module' like a G-Tech Pro? (According to reviews at least, pretty accurate. Is it more accurate than a modern cell phone? Are G-Tech's still rocking 20 year old technology?

Good news is that physics have not changed. An accelerometer is a pretty simple device, so what worked 20 years ago should still work today.

When weather gets nice I should pull mine out of the glove box and test it against the cell phone. I expect similar results.

 

[JohnnyK]

so what worked 20 years ago should still work today.

Well my question should have been phrased "Did it work accurately 20 years ago?". You have one I am assuming?

 

[STL. Mark]

Thanks to all you answered. I felt the biggest difference once the long tube headers were on. This is the original motor that came with the car, and it runs fine for cruising around, but would like to upgrade a bit with a new crate motor in the future.

 

[Woodchuck]

This has always puzzled me: why do (did?) manufacturers put out inaccurate info about c/r? They wouldn't say a crank journal was 3" if it was actually 3.125. I can't imagine the casting tolerances were that loose.

Who knows, although one can suppose for simplicity and/or consistency. Ford didn't bother to add in the volume created by the head gasket or valve reliefs so it was simply a matter of comparing the ratio of maximum cylinder volume to combustion area volume and calling it a day.