Torque = Driveability ? (Engine Masters LSA shootout)

[273]

Engine Masters did a LSA shootout 106 vs 112 vs 118, they basically all made the same peak hp but the tighter the lsa the more midrange torque for a better under the curve power.

Why I ask does Torque = Driveability because it gets stated all the time as fact any loss of low speed torque makes for poor driveability but as I keep seeing more test I don't think that generally way of thinking is entirely true, Take this LSA shootout, The wider the lsa would be considered the more street friendly grinds but obviously are making the least low end torque. Seems to be a contradiction of the two, in this case given up 30-40 lbs-ft = a more street friendly car, To me it seem torque has little to do with driveability take a /6 not much torque but super street friendly engine, It seems has more to do with overlap, throttle response, idle quality etc.. than any torque number ?

 

[Jersey Devil]

Engine Masters did a LSA shootout 106 vs 112 vs 118, they basically all made the same peak hp but the tighter the lsa the more midrange torque for a better under the curve power.

Why I ask does Torque = Driveability because it gets stated all the time as fact any loss of low speed torque makes for poor driveability but as I keep seeing more test I don't think that generally way of thinking is entirely true, Take this LSA shootout, The wider the lsa would be considered the more street friendly grinds but obviously are making the least low end torque. Seems to be a contradiction of the two, in this case given up 30-40 lbs-ft = a more street friendly car, To me it seem torque has little to do with driveability take a /6 not much torque but super street friendly engine, It seems has more to do with overlap, throttle response, idle quality etc.. than any torque number ?

I think it's about what is happening, Below 3,000rpms and part throttle. I think everyone at one point or another, forgets that dyno runs are ONLY at full throttle. You never see how the engine runs at 1/4 throttle and a light load. I would love to see that video.

 

[273]

I think it's about what is happening, Below 3,000rpms and part throttle. I think everyone at one point or another, forgets that dyno runs are ONLY at full throttle. You never see how the engine runs at 1/4 throttle and a light load. I would love to see that video.

Richard Holdener did a half throttle run and I forget exact numbers but made something like 80% of full throttle’s powers curve but more important the curve was similar shape just less power.

Yes I understand we’re mainly talking under 3000 rpm’s and a lot of dyno results don’t go that low, but you would have to assume on this test the 106 takes one hell of a nose dive below low the 3500 rpm’s compared to the 112/118’s and other dyno results have shown that to be very unlikely at least to 2500 ish rpm’s.

 

[Jersey Devil]

Richard Holdener did a half throttle run and I forget exact numbers but made something like 80% of full throttle’s powers curve but more important the curve was similar shape just less power.

Yes I understand we’re mainly talking under 3000 rpm’s and a lot of dyno results don’t go that low, but you would have to assume on this test the 106 takes one hell of a nose dive below low the 3500 rpm’s compared to the 112/118’s and other dyno results have shown that to be very unlikely at least to 2500 ish rpm’s.

I am in a different boat than 99% of the guys on here. I don't have a light a-body. With my 46rh, I am at <1/4 throttle 90% and 100% throttle the rest.

I am here because this site has the most discussions about small blocks. E, B and truck forums have alot less guys doing SBM mods.

I am also concerned about how it runs being stuck in traffic for a 1/2 hour more than WOT HP. I need my a/c, P/B, P/S in my pickup.

 

[273]

Plus if you compare to a stock motorhome 440 which would be very streetable but doesn't make much torque basically around 1 tq per cid which is a lot less than a the 106 lsa 1.33 tq per cid, never mind what a stock 360 or even a /6 has down low. Why wouldn't highway gears have a driveability issue since it throws tons of torque away compared to deeper gears if less torque made driveability issues?

 

[273]

You never see how the engine runs at 1/4 throttle and a light load. I would love to see that video.

As for comparing engines at part throttle and lighter loads, if you had two similar weight A Bodies one stock /6 and the other with that tunnel ram 440, and both left a street light at the same time and accelerated to the speed limit at the same (normal driving) rate (side by side) both engines would be producing a similar power curve as each other, even the /6 would have a lot of power to spare, you would have to make ridiculously low amount of torque to be an issue.

 

[273]

I am in a different boat than 99% of the guys on here. I don't have a light a-body. With my 46rh, I am at <1/4 throttle 90% and 100% throttle the rest.

I am here because this site has the most discussions about small blocks. E, B and truck forums have alot less guys doing SBM mods.

I am also concerned about how it runs being stuck in traffic for a 1/2 hour more than WOT HP. I need my a/c, P/B, P/S in my pickup.

Trucks (especially towing) need low speed Torque (Really needs low speed hp) why diesel are popular cause peak hp is at or near road speeds, you don't need to drop gears or as many to be in the powerband just push the throttle down, most cars don't need a lot of under 3,000 rpm power.

 

[EdM]

I went for torque in my 73 Mach 1. A 427 Windsor with the Edelbrock ProFlow 4 FI and a built AOD with a Lentech valve body. Always intended to be a street fun car. It is.

 

[Jersey Devil]

Engine Masters did a LSA shootout 106 vs 112 vs 118, they basically all made the same peak hp but the tighter the lsa the more midrange torque for a better under the curve power.

Why I ask does Torque = Driveability because it gets stated all the time as fact any loss of low speed torque makes for poor driveability but as I keep seeing more test I don't think that generally way of thinking is entirely true, Take this LSA shootout, The wider the lsa would be considered the more street friendly grinds but obviously are making the least low end torque. Seems to be a contradiction of the two, in this case given up 30-40 lbs-ft = a more street friendly car, To me it seem torque has little to do with driveability take a /6 not much torque but super street friendly engine, It seems has more to do with overlap, throttle response, idle quality etc.. than any torque number ?

They really need to do this test again, but account for the much lower cranking/dynamic compression of the wider LSA. How would they differ if they were advanced/retarded so that the Intake closing points were the same? Other option would be to change gasket thickness to bump/drop static compression.

How much of the lose is due to the drop in Dynamic compression, and how would the wider LSA's would fair if the engine was specifically built for it with Higher static compression like newer engines.

 

[Jersey Devil]

Engine Masters did a LSA shootout 106 vs 112 vs 118, they basically all made the same peak hp but the tighter the lsa the more midrange torque for a better under the curve power.

Why I ask does Torque = Driveability because it gets stated all the time as fact any loss of low speed torque makes for poor driveability but as I keep seeing more test I don't think that generally way of thinking is entirely true, Take this LSA shootout, The wider the lsa would be considered the more street friendly grinds but obviously are making the least low end torque. Seems to be a contradiction of the two, in this case given up 30-40 lbs-ft = a more street friendly car, To me it seem torque has little to do with driveability take a /6 not much torque but super street friendly engine, It seems has more to do with overlap, throttle response, idle quality etc.. than any torque number ?

Other test I would like to see, Change the durations and LSA to maintain the same overlap.
228/234 on 106 lsa vs. 232/236 on 108 lsa vs. 236/242 on 110lsa vs. 240/246 on 112 lsa

 

[Newbomb Turk]

Other test I would like to see, Change the durations and LSA to maintain the same overlap.
228/234 on 106 lsa vs. 232/236 on 108 lsa vs. 236/242 on 110lsa vs. 240/246 on 112 lsa

I’d do the test but you’d pay for it.

As I’ve said many times, you can’t achieve over 100% VE without overlap.

If you need the duration and keep the overlap the same you’ll see the same thing. It will run 300-500 rpm higher and get its brains beat out everywhere else

The other irritating thing is talking about low speed “driveability” and overlap.

90% of the issues comes from guys never learning how to tune for it. The other 10% is shitty converters and the wrong gearing.

 

[mbaird]

Drivability means more than can it do it . My Swinger has a 408 with a 108 cam and my Barracuda had a 360 ( soon to be a 408) with a 112 cam . The Dart can drive in town but it’s not near as smooth as my Barracuda. I am sticking with the 112 in the new 408 because most of my drive time in it is below 3500.

 

[Newbomb Turk]

Drivability means more than can it do it . My Swinger has a 408 with a 108 cam and my Barracuda had a 360 ( soon to be a 408) with a 112 cam . The Dart can drive in town but it’s not near as smooth as my Barracuda. I am sticking with the 112 in the new 408 because most of my drive time in it is below 3500.

I know what it means. My cam is on a 105 and my wife can drive it.

It’s 90% tuning like I said.

 

[Jersey Devil]

Drivability means more than can it do it . My Swinger has a 408 with a 108 cam and my Barracuda had a 360 ( soon to be a 408) with a 112 cam . The Dart can drive in town but it’s not near as smooth as my Barracuda. I am sticking with the 112 in the new 408 because most of my drive time in it is below 3500.

This is what Howard's recommend for my TFS190 Headed 390 Magnum build.

 

[MOPAROFFICIAL]

Engine Masters did a LSA shootout 106 vs 112 vs 118, they basically all made the same peak hp but the tighter the lsa the more midrange torque for a better under the curve power.

Why I ask does Torque = Driveability because it gets stated all the time as fact any loss of low speed torque makes for poor driveability but as I keep seeing more test I don't think that generally way of thinking is entirely true, Take this LSA shootout, The wider the lsa would be considered the more street friendly grinds but obviously are making the least low end torque. Seems to be a contradiction of the two, in this case given up 30-40 lbs-ft = a more street friendly car, To me it seem torque has little to do with driveability take a /6 not much torque but super street friendly engine, It seems has more to do with overlap, throttle response, idle quality etc.. than any torque number ?

If you're constantly having traction issues it might be.

 

[BSB67]

I know what it means. My cam is on a 105 and my wife can drive it.

It’s 90% tuning like I said.

Can you tell us more about your cam, car, weight, et, mph, idle Rpm in gear, converter and gear?
Thanks

 

[mbaird]

I know what it means. My cam is on a 105 and my wife can drive it.

It’s 90% tuning like I said.

Never said you didn’t know.
But it’s a preference thing.
Does your wife grab the keys to go to the grocery store ( old timey word..lol) or take the kids to school ? Or drive 200+ miles in it . I do use my barracuda like that so my preference is for a smooth idle and butt loads of torque.

 

[273]

Never said you didn’t know.
But it’s a preference thing.
Does your wife grab the keys to go to the grocery store ( old timey word..lol) or take the kids to school ? Or drive 200+ miles in it . I do use my barracuda like that so my preference is for a smooth idle and butt loads of torque.

I'm not questioning people choosing better idle over low/mid range torque.

You just keep hearing on here and other sites, especially when dealing with smaller cid, when choosing mods like cam, heads, intake, carbs etc... first thing out of a bunch of people's mouth's better watch out for bottom end torque or driveability will go out the window but you hear it even with big blocks especially 383/400 but even 440. But as I see more builds and there dyno results this basic assumption seems faulty. I think what were really taking about is overlap maybe mixed with throttle response, not low speed torque.

I also feel what Newbomb Turk said about tunning is likely more often the problem.

 

[mbaird]

I'm not questioning people choosing better idle over low/mid range torque.

You just keep hearing on here and other sites, especially when dealing with smaller cid, when choosing mods like cam, heads, intake, carbs etc... first thing out of a bunch of people's mouth's better watch out for bottom end torque or driveability will go out the window but you hear it even with big blocks especially 383/400 but even 440. But as I see more builds and there dyno results this basic assumption seems faulty. I think what were really taking about is overlap maybe mixed with throttle response, not low speed torque.

I also feel what Newbomb Turk said about tunning is likely more often the problem.

For sure many built engine drive like crap due to the tune .
I built a 454 for a 72 Monte Carlo I had and it was a dog !
In retrospect I am pretty sure my tune was the culprit. that was long ago before I understood timing curves and carb tuning. And I am still a comparative noob on the subject .

 

[RustyRatRod]

Oh. My. GAWD.

 

[Ottmundr]

As for comparing engines at part throttle and lighter loads, if you had two similar weight A Bodies one stock /6 and the other with that tunnel ram 440, and both left a street light at the same time and accelerated to the speed limit at the same (normal driving) rate (side by side) both engines would be producing a similar power curve as each other, even the /6 would have a lot of power to spare, you would have to make ridiculously low amount of torque to be an issue.

Seriously? this kind of math question? I've hated this kind of stupid riddle since the 4th grade.

q: If the A body with the tunnel ram 440 and a 3/4 race cam leaves Cleveland at 3:18pm, and the other A body with the Offy intake/Dutra duals /6 and a RV cam leaves Salt Lake City at 4:26, both accelerating at the same speed which arrives at the Mustang Ranch outside of Reno Nevada first?
a: They never get there because a Mopar driver doesn't need to go to a whorehouse!

 

[junkyardhero]

*walks thru the doors and up to the bar*

barkeep, i'll have your finest sarsparilla!

*hears talk of tq per cid, sees dyno graphs, notices everybody is on their boo-sheet*

ya know what fella, you can hold on that cool one. here's two-bits for your trouble

*turns and walks right back out the door*

 

[Newbomb Turk]

Never said you didn’t know.
But it’s a preference thing.
Does your wife grab the keys to go to the grocery store ( old timey word..lol) or take the kids to school ? Or drive 200+ miles in it . I do use my barracuda like that so my preference is for a smooth idle and butt loads of torque.

No, but she CAN drive it anywhere.

I drive it everywhere except for 200 mile trips.

My point is driveability is TUNING. If I posted my combo most guys would say it isn’t driveable because I’ve heard it a million times.

It idles clean, stays at not hotter than 170 on 100 plus degree days and thats only at stop lights and runs on pump gas at 11.5:1.

If my cam shows up this week I COULD be on the dyno in less than a month unless I get bogged down on pushrods.

It will have a tunnel ram this time, with two 830’s and it will be 12.2x on pump gas. I can’t remember the second digit.

And it will drive better than the last engine.

It CAN idle as low as 700 but I don’t let it get below 950 and would rather it’s 1k.

I certainly could change the gears and take it on a 200 mile drive. I don’t see it happening but I could do it.

 

[BSB67]

No, but she CAN drive it anywhere.

I drive it everywhere except for 200 mile trips.

My point is driveability is TUNING. If I posted my combo most guys would say it isn’t driveable because I’ve heard it a million times.

It idles clean, stays at not hotter than 170 on 100 plus degree days and thats only at stop lights and runs on pump gas at 11.5:1.

If my cam shows up this week I COULD be on the dyno in less than a month unless I get bogged down on pushrods.

It will have a tunnel ram this time, with two 830’s and it will be 12.2x on pump gas. I can’t remember the second digit.

And it will drive better than the last engine.

It CAN idle as low as 700 but I don’t let it get below 950 and would rather it’s 1k.

I certainly could change the gears and take it on a 200 mile drive. I don’t see it happening but I could do it.

Any response to #16?

 

[Newbomb Turk]

Any response to #16?

What else do you want to know? I answered everything I can.