Exactly what I’m looking to do.Honestly if I was going to do it over, I would do an Ebay turbo and well designed exhaust manifold. Way more work though
Exactly what I’m looking to do.Honestly if I was going to do it over, I would do an Ebay turbo and well designed exhaust manifold. Way more work though
Well...LOL, good as they can get. The 170 can actually knock down pretty decent mileage. The 225 can do "ok". I love the off idle torque the 225 has though. It's pulling pretty much as soon as the throttle is cracked. lolAnd good gas millage
Yeah that's about what mine gets. I don't mind the intercooler rigamoroe, I can make that look neat. It's all the other crappola that goes with it. I won't get one without it being both liquid and oil cooled, so there's more lines. Also the blow off valve and whatnot, so there's more stuff. It's just too much crammed in the small space of an early A body engine bay, IMO. If I thought I could do it and keep it neat, I probably would. All that said though, I'm having an absolute blast with it naturally aspirated.A basic turbo install doesn't have to have all that intercooler stuff. One install I did took the vehicle from a best of 23 mpg straight to a hair under 30 mpg while almost doubling the power. I was sold.
If you do the work yourself it costs less than headers-intake-carb.
My 225 gets right around 17mpg
Do you remember if they included upgrading the exhaust? Even Chrysler didn't use a different exhaust manifold with a larger outlet, but they should have.The Direct Connection Racing manuals (1978 version) says the SuperSix upgrade is worth 7% more horse power.
Gotchya. Then 7% sounds like a fair number. I would think modifying a stock manifold to a 2.5" or 2.25" outlet with a bigger pipe all the way back would net even more.No, just the intake upgrade.
When we were racing my wife's '73 Duster, the 2 1/2" exhaust pipe was the most significant upgrade. The second was a TransGo shift kit in the transmission. The SuperSix and the Autolite 2100 was a distant third. Upgrading to a Offenhauser manifold with the same carb didn't make any difference in elapsed times.
Don't matter, if he didn't open up the outlet on the manifold flange bigger exhaust won't do squat
So the guy has a dilemma: I remember 39 years-ago when I last drove this car that the original 170 was pretty sluggish (around 100 hp?). I would like just a little more pep. (I'm not trying to turn it into a muscle car).
Does anyone know how much HP is created with the two barrel carb with the two barrel intake on a 170?
My other option is...I have a spare rebuilt 1972 225 that only has about 1,500 miles on it that will get me roughly 145 hp. Will I notice a big difference with the extra 45 hp? Obviously a lot more work to do the engine swap.
I don't remember if I had any work done on the 170. I know it never used any oil and the odometer says 165k.
Opinions? Thoughts? You guys are great. Thanks
yes, it definitely does matter. anything bigger than the actual outlet diameter of the manifold flange doesn't help flow a bit. the 1-3/4 to 1-7/8" hole in the manifold flange is a bottleneck!!!! It doesn't take much with a die grinder and burr, to open the manifold opening. Don't worry, there's lots of meat there// you won't be "too thin" but it DOES make a difference!!!!
Rusty Rat Rod had a thread with pix about this very thing, about a year ago right here........
and the last one I did that treatment to, as cast, the exhaust opening was way off center, compared to a flange gasket bolted up loosely as a guide// so that gives you a chance to "square things up" at the same time. (most of the flange gaskets I have found with that bolt spacing are a 2-1/4" hole, so that's as far as I grind)
Easy boy, this ain't my argument.Really, do you have a dyno split from before and after the modification? How about a time slip from the track? Do you have anything other then Rusty's butt-o-meter, that shows he thought there was an improvement?
A 2 /12" exhaust pipe bolted directly to the exhaust manifold on my wife's Duster was worth 2 tenths on the 1/8th track that we raced at.
Gases expand once it gets down the pipe, exhaust ports are generally smaller than the tubing headers coming off it. Motorcycles have expansion chambers to make power, my Bul had one iirr 1-18 to 4” then back down to exit at 2”Why does everyone seem to require a time slip for things like this?
But you don't understand bottleneck? That outlet is 1-7/8" on most /6s. So how can something larger than that, bolted on behind the said bottleneck, flow any better than that which flows THRU, that size hole????
I definitely wouldn't want anything smaller than the opening for sure.
For 2 tenths difference, that could be coincidence. Or temp. Or reaction. Or any number of things between the 2 runs.
The larger pipe size certainly won't hurt flow... I get that. But I don't get how it can help it either, unless everything is opened to that dimension.
Why does everyone seem to require a time slip for things like this?
Because the ole butt-o-meter is not very accurate.