170/6 build plus questions!

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easymotorspo

easymotorspo

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Car: 1968 Plymouth Valiant 100, 170/6, 3 on tree, 3.23 sure grip, frame tied, swaybars front & rear, PST bushings, sector support kit and needle bearing idler arm, 11/16 tie rod ends and adjusters, fast ratio manual steering, manual brakes, 15x7 (4.5 bbp) steel wheels, electronic ignition, flowkooler waterpump, 180° thermostat, 2.5 TTI mandrel bent exhaust with super turbo nuffler, alternator switched to driverside, & Mercedes Benz thermostatic clutch fan.

Driving: around town, Blue Ridge Parkway cruising, (no racing or pushing hard)

Project: getting ready to put a Peanut Head ( rebuilt, polished, ported, stock size back cut valves), milled .100, (piston to valve and piston clearances checked)port matched to Super Six intake & professional built BBD Carb.

Question: anyone put a Super six system on a 170? Results?

Question: I have a split exhaust manifold, looking much like Dutra Duals, and a Y pipe. Should I put this system on and plumb it into 2.5 exhuast OR keep my factor exhaust manifold with full 2.5 TTI mandrel bent exhaust?

(I realize all answers to questions are opinions)
 
easymotorspo said:
Car: 1968 Plymouth Valiant 100, 170/6, 3 on tree, 3.23 sure grip, frame tied, swaybars front & rear, PST bushings, sector support kit and needle bearing idler arm, 11/16 tie rod ends and adjusters, fast ratio manual steering, manual brakes, 15x7 (4.5 bbp) steel wheels, electronic ignition, flowkooler waterpump, 180° thermostat, 2.5 TTI mandrel bent exhaust with super turbo nuffler, alternator switched to driverside, & Mercedes Benz thermostatic clutch fan.

Driving: around town, Blue Ridge Parkway cruising, (no racing or pushing hard)

Project: getting ready to put a Peanut Head ( rebuilt, polished, ported, stock size back cut valves), milled .100, (piston to valve and piston clearances checked)port matched to Super Six intake & professional built BBD Carb.

Question: anyone put a Super six system on a 170? Results?

Question: I have a split exhaust manifold, looking much like Dutra Duals, and a Y pipe. Should I put this system on and plumb it into 2.5 exhuast OR keep my factor exhaust manifold with full 2.5 TTI mandrel bent exhaust?

(I realize all answers to questions are opinions)
Click to expand...

I say on the exhaust it depends. Have you ported the stock manifold outlet to match the 2.5 pipe? If not, that larger pipe is not working to its full potential. Check this thread out.

Exhaust Manifold Mod

There is plenty of room to port the outlet all the way to 2.5". I've always thought the slant six would respond better to a good single exhaust rather than a dual. I think the best would be like two 2" pipes that Y into a larger single, say 2.5 or even 3".

And yes, I can tell a nice difference in the ported manifold on my stock 170, even though I am still running the 1 7/8 pipe. I cannot wait to see the gains from the 2.5" pipe when I add it.
 
...and on your super six question, I have one. I plan on installing the Weber 32/36 progressive two barrel if I leave the 170 in long enough.....and I likely will.
 
RustyRatRod said:
...and on your super six question, I have one. I plan on installing the Weber 32/36 progressive two barrel if I leave the 170 in long enough.....and I likely will.
Click to expand...
Thanks RRR, in reference to the to the dual exhaust thought, the way you described it is what I envisioned as the opening on my split manifolds are 2", my Y is a flowmaster, 2-2" pipe into 2.5 pipe then connect that to the rest of my current TTI exhaust and sell my 2.5 head pipe.
 
Rob, what's your thoughts on these necked down "merge collector" headers? Supposes to keep velocity up....?
"....That keeps the gas velocity up for a bit longer, helping to scavenge neighboring (upstream branch) pipes...." header only talk? Don't know what effect it would have on a lower speed slant, although any exhaust pulse is hypersonic.
exhaust_technology_04.jpeg
Screenshot_20201001-160108_Free Adblocker Browser.jpg
 
easymotorspo said:
Thanks RRR, in reference to the to the dual exhaust thought, the way you described it is what I envisioned as the opening on my split manifolds are 2", my Y is a flowmaster, 2-2" pipe into 2.5 pipe then connect that to the rest of my current TTI exhaust and sell my 2.5 head pipe.
Click to expand...

I think that would be the best idea. Also, I would be interested in that TTI head pipe, as I want one to modify for the 170. I already have one and I was going to leave it as is for a later possible 225 swap.
 
RustyRatRod said:
I think that would be the best idea. Also, I would be interested in that TTI head pipe, as I want one to modify for the 170. I already have one and I was going to leave it as is for a later possible 225 swap.
Click to expand...
Sounds great, if I do the Y, it's yours. Now to make a dicision.......
 
pishta said:
Rob, what's your thoughts on these necked down "merge collector" headers? Supposes to keep velocity up....?
"....That keeps the gas velocity up for a bit longer, helping to scavenge neighboring (upstream branch) pipes...." header only talk? Don't know what effect it would have on a lower speed slant, although any exhaust pulse is hypersonic.
View attachment 1715604740 View attachment 1715604741
Click to expand...

I think it's a good idea. You already know the slant's exhaust grouping and firing order are perfect for scavenging with the dual 3 into 1 manifolds or headers. So I think that type collector would just "add to" something already good.
 
easymotorspo said:
Sounds great, if I do the Y, it's yours. Now to make a dicision.......
Click to expand...

Thanks. Just let me know. I chose not to do the Y or split manifolds or headers, since my friend Freddie did suck a great job with the stock manifold.
 
easymotorspo said:
Car: 1968 Plymouth Valiant 100, 170/6, 3 on tree, 3.23 sure grip, frame tied, swaybars front & rear, PST bushings, sector support kit and needle bearing idler arm, 11/16 tie rod ends and adjusters, fast ratio manual steering, manual brakes, 15x7 (4.5 bbp) steel wheels, electronic ignition, flowkooler waterpump, 180° thermostat, 2.5 TTI mandrel bent exhaust with super turbo nuffler, alternator switched to driverside, & Mercedes Benz thermostatic clutch fan.

Driving: around town, Blue Ridge Parkway cruising, (no racing or pushing hard)

Project: getting ready to put a Peanut Head ( rebuilt, polished, ported, stock size back cut valves), milled .100, (piston to valve and piston clearances checked)port matched to Super Six intake & professional built BBD Carb.

Question: anyone put a Super six system on a 170? Results?

Question: I have a split exhaust manifold, looking much like Dutra Duals, and a Y pipe. Should I put this system on and plumb it into 2.5 exhuast OR keep my factor exhaust manifold with full 2.5 TTI mandrel bent exhaust?

(I realize all answers to questions are opinions)
Click to expand...


If the bottom half rebuilt? Or stock. Split dual manifolds will have an increase in h.p and mileage versus the stock logs. I think the Dyno showed 12 h.p increase. My buddy has a super six on his 170 helped it out, but still not as fast as a 225 with a stock one barrel. but if you come across a 225 the upgrade it’s self will make a world of difference. All you would need to do is bolt on that head and let it rip!
 
Slantsix64 said:
If the bottom half rebuilt? Or stock. Split dual manifolds will have an increase in h.p and mileage versus the stock logs. I think the Dyno showed 12 h.p increase. My buddy has a super six on his 170 helped it out, but still not as fast as a 225 with a stock one barrel. but if you come across a 225 the upgrade it’s self will make a world of difference. All you would need to do is bolt on that head and let it rip!
Click to expand...
I have three 225's but want to stay with the 170. The bottom half is nice and tight. No blow by, current compression ratio are all close to each other, oil pressure is 70-90lbs
 
easymotorspo said:
So it's not to hard to not that out to 2.5?
Click to expand...

Well it is for me. I have zero talent with a hand held grinder. lol Freddie is a master with one. Did you look at thread I linked to to see the job he did?
 
easymotorspo said:
I have three 225's but want to stay with the 170. The bottom half is nice and tight. No blow by, current compression ratio are all close to each other, oil pressure is 70-90lbs
Click to expand...

There's zero wrong with a 170. I love mine. It's very snappy. More so than I ever imagined. I assume it's because of the short stroke that allows it to spin up quick, but whatever it is, I like it.
 
easymotorspo said:
Yes I did. I think I could do it. I have everything except the bits..
Click to expand...

Well, now you know there's plenty of meat there. I never wouldda thought it would have been thick enough.
 
RustyRatRod said:
I think it's a good idea. You already know the slant's exhaust grouping and firing order are perfect for scavenging with the dual 3 into 1 manifolds or headers. So I think that type collector would just "add to" something already good.
Click to expand...

This was in regards to the factory slight pinch on the bottom of the slant "6 into 1" log manifold that was smoothed out on your example. These examples were NASCAR spec stuff, maybe out of the league of a slants cam specs. Not a student of gas flow myself.
 
pishta said:
This was in regards to the factory slight pinch on the bottom of the slant "6 into 1" log manifold that was smoothed out on your example. These examples were NASCAR spec stuff, maybe out of the league of a slants cam specs. Not a student of gas flow myself.
Click to expand...

Just eat more tacos. You will be.
 
easymotorspo said:
Car: 1968 Plymouth Valiant 100, 170/6, 3 on tree, 3.23 sure grip, frame tied, swaybars front & rear, PST bushings, sector support kit and needle bearing idler arm, 11/16 tie rod ends and adjusters, fast ratio manual steering, manual brakes, 15x7 (4.5 bbp) steel wheels, electronic ignition, flowkooler waterpump, 180° thermostat, 2.5 TTI mandrel bent exhaust with super turbo nuffler, alternator switched to driverside, & Mercedes Benz thermostatic clutch fan.

Driving: around town, Blue Ridge Parkway cruising, (no racing or pushing hard)

Project: getting ready to put a Peanut Head ( rebuilt, polished, ported, stock size back cut valves), milled .100, (piston to valve and piston clearances checked)port matched to Super Six intake & professional built BBD Carb.

Question: anyone put a Super six system on a 170? Results?

Question: I have a split exhaust manifold, looking much like Dutra Duals, and a Y pipe. Should I put this system on and plumb it into 2.5 exhuast OR keep my factor exhaust manifold with full 2.5 TTI mandrel bent exhaust?

(I realize all answers to questions are opinions)
Click to expand...
Isn’t a 170 already a near zero deck engine? Meaning that at TDC the pistons are at or very close to block deck height. And you are putting a cylinder head on it that was cut .100
Have you ran those numbers through a static compression calculator.
Cutting a 225 head .100 is done, but those blocks have pistons around .180 in the hole.
 
my68barracuda said:
Isn’t a 170 already a near zero deck engine? Meaning that at TDC the pistons are at or very close to block deck height. And you are putting a cylinder head on it that was cut .100
Have you ran those numbers through a static compression calculator.
Cutting a 225 head .100 is done, but those blocks have pistons around .180 in the hole.
Click to expand...

Yes, the 170 is considered a zero deck height engine. I've never measured it.....and in fact, I have one out here with the head off. I may run out and measure it if I can get the headache to ease off some.
 
From what I have learned through this process, everything (170 wise) revolves around the lift on the cam when you mill the head such as I have. Do to the fact that my cam is stock, I shouldn’t have a issue with valve/piston issues. According to the calculations I should have a bump up in compression, increase in hp/tq, and everyone says a little more “seat of the pants” fun. Although I will admit that the majority of modifications, motor & chassis wise, is because I love to tinker & enjoy doing it with my kids. (16,15 & 8).
 
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