Advice: Heavy VAN TPI -torque and MPG build: Knock Risk

[skinny z]

Get on Thirdgen and hunt down fast355, right up his alley.

I was just going to add that.
He's got a big heavy cargo van he uses for towing and has results that look to be remarkable.
I'll give him the heads up here.
Maybe some good will come out of it.

[skinny z]

Here's a link to his profile page at Thirdgen.org if you're interested.

https://www.thirdgen.org/forums/member. ... styleid=53

[racprops]

I have reached out to Fast355 on thirdgen a couple of days ago so far no response.

ARich

[skinny z]

I have reached out to Fast355 on thirdgen a couple of days ago so far no response.

ARich

Me too.
Reading through some his threads might give you some insights.

[Circlotron]

High torque cams don't give the best mpg, they waste fuel creating too much vacuum at cruise. Egr could fix that.

What about some kind of load actuated flap valve that allows hot air intake at part throttle but cold air above a certain throttle opening?

Hot air/manifold can be good for economy with a carb, doubt it helps with a good set of injectors.

I read the subject line as TBI rather than TPI. If it actually was TBI then it might have helped the same way is does with a carb re wet manifold and all. The other reason I’m thinking hot air would help part throttle economy even with good injectors is because hot air is less dense so you need a wider throttle opening, so that means less vacuum and consequently lower pumping losses. YMMV.

[Tom68]

What about some kind of load actuated flap valve that allows hot air intake at part throttle but cold air above a certain throttle opening?

Hot air/manifold can be good for economy with a carb, doubt it helps with a good set of injectors.

I read the subject line as TBI rather than TPI. If it actually was TBI then it might have helped the same way is does with a carb re wet manifold and all. The other reason I’m thinking hot air would help part throttle economy even with good injectors is because hot air is less dense so you need a wider throttle opening, so that means less vacuum and consequently lower pumping losses. YMMV.

My bad, did misread.

[RCJ]

What mpg do you expect?

[racprops]

Well based on these kind of readings:

Speeds, RPMs and MPG 03 Ford Explorer with Stock 3.73 Rear end.

MPG testing Upgrade Scan Gauge II, using trip MPG readings.
1AM I17 North from Cactus to 101 and south 101 to Cactus Temp 70Degrees Two runs each way. No wind.

The latest one of four cars I have tested this on:

Discovered that my rear RPMs and Speed do not match the calculator so corrected rear end gears to match real world readings:

Took her out again tonight. 60MPH and 70MPH TRUE by GPS. I was concerned when the calculator was off.

SO reset by this real world readings:
50MPH 1521 = AVG 26/27MPG Reads like a 3.55 Rear end.

Recalculated 2nd Overdrive with 3.55: DOD Is Double Over Drive
42MPH in 5th @ 1270RPMs = DOD = 60MPH
45MPH in 5th @ 1380RPMs = DOD = 65MPH
49MPH in 5th @ 1480RPMs = DOD = 70MPH = 29MPG
52MPH in 5th @ 1580RPMs = DOD = 75MPH
56MPH in 5th @ 1700RPMs = DOD = 80MPH
59MPH in 5th @ 1800RPMs = DOD = 85MPH = 26MPG

Due to traffic I only got these lowest and highest readings Lowest I read was 49MPH by GPS and got 29MPG and highest was 59MPH and read 26MPG. SO IF the SUV can get the same MPG at the Same RPMs then at the higher speed in double overdrive that will mean at 70MPH it will be doing 29MPG and at 85MPH getting 26MPG.

Of course these projections do not, cannot show what effects wind resistion and rolling resistion will be and how they will affect the real world MPG. But I believe it will only be minor.

Of course this will only help with higher speeds, mainly on highways.

And the costs of building it and installing it will take some time to be paid off by the money I will be saving by the lowered costs of driving in gas savings.
So it is a cost VS benefits calculation, so the cheaper the cost the better.

Here is an ODD thing about the plan for a double overdrive.

The RPM and Miles per hour range is from 49MPH = 1480 RPMs to 59MPH @ 1800 RPMs in the Ford Explorer in fifth gear.

The calculator shows that adding in the double overdrive those speeds and RPMs corresponds to: 5th gear 49MPH = 1480 RPMs will be in 6th gear will be 60MPH @ 1480RPMs and that 59MPH @ 1800 RPMs will be 85MPH….

The only thing that will be a facture will be how much wind resistion will hurt my MPG…which seems to not to all that it is trumped up to be.

Because a 2019 Chevy Express van (A BIGGER BOX) is officially reported by its sticker to do 29MPG highway. My 93 G20 is even smaller and lower that that monster.

I Have a great picture of a window sticker from a 2019 Express van showing 29MPG highway and a Express VAN (A tall long big van) and my little Explorer...

Can't load it here.

Rich

[skinny z]

I have reached out to Fast355 on thirdgen a couple of days ago so far no response.

ARich

Me too.
Reading through some his threads might give you some insights.

I just had a conversation with Fast355. Seems he has had some discussion with the OP but nothing ever came of it.

[racprops]

"I just had a conversation with Fast355. Seems he has had some discussion with the OP but nothing ever came of it.
Kevin"

What is OP?? Is he dropping out of thirdgen??

I am also into Ford Panther model cars and we lost one of our greatest poster when a Drock dropped out.

Rich

[skinny z]

What is OP??

I use it as the acronym for Original Poster.

As for Fast 355, I think he's a thridgen.org mainstay.

[mag2555]

If the thing has steel rims then reducing rotational mass at all 4 corners with lighter rims can be a surprising plus in both mileage and performance gains!

All too often we dive under the hood for improvement’s!

[BLSTIC]

Things like tapered squish zones may help. Or their poor cousin, grooves. (both seems about allowing flame front access to the full bore sooner without reducing charge motion brought on by the squish)

[rgalajda]

High torque cams don't give the best mpg, they waste fuel creating too much vavuum at cruise. Egr could fix that.

Can you expand on this ?

[racprops]

" Tom68 wrote: ↑Mon Apr 25, 2022 4:38 pm
High torque cams don't give the best mpg, they waste fuel creating too much vavuum at cruise. Egr could fix that.

by rgalajda
Can you expand on this ?"

Tom I believe is talking about Pumping Loses, Where the high vacuum of a nearly closed throttle and the resulting high vacuum is its self fighting the engine, it is trying to stop the engine. This is one of the features that helps diesels get better MPG, NO throttle plate, no vacuum, diesels control power by changing fuel injection, so there is no vacuum to fight so no pumping loses.

Here is a tread on this: https://ecomodder.com/forum/showthread. ... 34424.html


And right here: viewtopic.php?t=43216

My plan if this shows up is to add EGR, doing so can as I have read can swamp the engine forcing more throttle which lower engine vacuum.

It is funny how we are told the higher the vacuum the better the MPG will be BUT only to a point.

Rich