Mo Powa! Betta MPG! Pass Emissions?

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Aug 8, 2014
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For those of you clicking on this thread hoping that I've found the golden ratio to make the 80 Series even better at everything, I appologize.
Alas, I am just posting this in the hopes to get a conversation going about modernizing this rig to take it to the next level.
One could argue that its reliability comes from it's simplicity but there is definitely something to be said about the evolution of the automobile and all of the advancements that have come with it.

I am not going to get too deep into the conversation in this first post.
The fact is I have typed out some long-winded example filled version of this thread at least 3 times now and always delete it becasue I get lost in the sauce (both figuratively and literally (well kinda)
I drink sometimes... What are ya gonna do?

Anyway, the premise is to see what other ideas people have come up with to try to wrangle a bit more of everything out of this rig but there is a catch...
I live in Colorado.
I also live in one of a handful of counties in CO. that require a CARB style emissions check every other year so that is something that I have to think about with every mod to get power or MPG or whatever.
No LS swap for me.

To get things started, allow me jump off with a modern trans swap.
Think 8-10 speeds with much more modern controls.
This was the first... OK technically second (I won't get into that now) idea on my list.
I went so far as to get the transmission before I even had the truck and order up an adapter to make it all work.

I am doing an 8HP70 swap into my rig and from what I gather this offers a significant improvement in both drivability and MPG.
I can also imagine that this could be improved upon with some optomizing to take advantage of the new gear ratios, which I will also get into a bit later.

OK. I am going to stop there.
Feel free to post up any ideas you might have dreamt up and/or ask any queastions you might have on this topic.

I will elaborate on my current plan and toss out some ideas when I am focused enough to do so.

Until next time........
 
Golden ration…I’ve been working on this problem for years. Turbo, 488’s, intercooler, big brake system, next is a trans swap from @Cruisers and Co. By the time I finish it should be time to retire, but I won't have any $ left to retire.
 
This search has led me to where my 80 is today (and also our catalog of products). For me the 80 needs to be able to maintain highway speed up every grade, take me and my family everywhere reliably, drive 1000 miles wheel hard trails and then take us home.

The setup today consists of a turbocharged 1FZ (c&c turbo obviously 🤣, factory ecu), C&C intercooler, an A750F 5 speed (from a 100 series), hf2av w/ 3:1’s, 4:10 diff gears w/ oem lockers and 35” tires.

I can drive from Denver to the Rubicon, run it, and come back with the AC on. Drive to remote parts of Utah, Wyoming or Montana without any worries.

What I like about my set up is I can share or receive parts like driveshafts, alternator, dizzy, water pump, ps pump etc. A huge reason we did not do the 8HP. We lost a couple driveshafts this year on the rubicon and people in our group had spares. When traveling with others you aren’t having to be self reliant.

It cruises amazing on the highway. I was nice to it yesterday cruising to Colorado Springs and back at 70 mph average and got 15 mpg. Want to go up i70? set it and forget it… Offroad is controlled and able to go anywhere I really want to take it.

Not sure where you’re at but obviously front range CO. Shop is in Westminster if you want to come chat about it
 
@Cruisers and Co I am in Longmont and had no idea there was a Land Cruiser shop so close.
I mean it is Colorado so I am not surprised there is one so close but good to know and I will def stop by sometime to chat.
Anyway, back on the transmission talk.
I had some thought last night on axle gearing as I struggle to find anyone that has the 4.88s I want in stock.
Let's just assume I am doing an 8hp with the stock transfer case.
I am running 35 inch tires currently.
The 8hp has a 8th gear ratio of 0.67:1 vs the 0.75:1 on the A343F that is currently in my truck.
With that in mind does it make more sense to run a 5.29 ring and pinion with my 35s or stick to the 4.88s that everyone does with 35s?

So with a stock trans and 35s you would be at about 2460rpm in 4th at 70mph with 4.88 gears.
That same set up with the 8HP would put you at about 78mph.
Now if the goal was to run the same speed with the 8hp you could drop that RPM back to about 2200 to maintain 70mph with 4.88s
That sounds like a sure plan for better fuel economy especially if you think about the extra gears available to keep keep the RPM lower while changing gear to maintain highway speeds and the general efficiency improvements of the 8hp over the A343F.

However, If you were looking for a bit more off road improvement, you could swap to a 5.29 axle gear and actually still be running at lower RPM (2380 vs 2460) with the 8HP vs the A3434F at 70mph

Yes there is a bit more to fuel economy than just RPM at any speed but in general fewer RPM usually equals better MPG.

This thread is not really about overall off road performance but we can't go without mentioning the ever-so-important craw ratio improvements from switching to the 8hp.
All things being equal, the 8hp almost doubles your crawl ratio and only gets better with the 5.29s vs the 4.88s

Of course I bring most of this up for conversations sake because I am not running a stock transfer case.
Ok I am just going to say it.
My name is Bill and I am going to put a Land Rover part in my Land Cruiser.
I am speaking of none other than the infamous LT230 transfer case.
This throws all of my previous conversation out the window becasue the LT230 has a 1.2:1 high range ratio and realistically when it comes time to do this swap I will be looking at the stock 4:10s or maybe some 4:30s for my axles to play nice with all the RPM vs speed calculations.

I only ordered the 4.88s (3 times now and still have not received any yet) because I am looking to do some wheeling this spring and summer and all the good stuff won't be happening until winter where I will swap in my new engine(rebuilt 1FZ) /trans/transfer case combo.

Still open to conversation on the transmission topic but I think I have covered my opinion and am ready to move on to engine efficiency.

Maybe now is a good stopping point so this does not get too wordy all in one sitting but let me just get things started by tossing out a couple ideas.

1. Higher compression (probably 10:1)
2. Slight overbore (0.5mm probably to clean thigns up)
3. Low boost, intercooled turbo set up.
4. Reduce parasitic engine losses

There are plenty more details but thats for next time.
Until then...
 
EPS (electric power steering) would be a great upgrade for multiple reasons... 1) no more power steering pump or fluid, 2) variable rack assistance (tunable) and even engine off.
 
EPS (electric power steering) would be a great upgrade for multiple reasons... 1) no more power steering pump or fluid, 2) variable rack assistance (tunable) and even engine off.
Yep I'm going all in with the electric bits.
My Power steering is already groaning a bit and the steering is pretty stiff so electric power steering is at the top of the list
Then an electric brake booster
Brushless PWM rad fans.
Electric AC
Maybe more. 😉
 
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To be clear any electric power steering set up strong enough for this rig is still going to have fluid.
Essentially it will just be an electric hydraulic pump with an attached fluid reservoir.
This unit found in many Volvos seems to be a good option.
power steering pump.webp


Ok back on to the engine as mentioned in my other post.

It may seem counterintuitive to want to bump up compression if the plan is to add a turbo in the future.
However, with high compression comes higher efficiency and typically with higher efficiency comes more MPG and maybe a few extra ponies in the process.
When I say I few I do mean just a handful.
The interwebs say gains of 2-4% can be had with every point bump in compression and that is without taking advantage of any tuning that might benefit from a bump so going from 9:1 to 10:1 could net 5-8 hp in a perfect world.

The interwebs also say that the stock ECU can likley handle the bump in compression well enough to pass an emissions check provided you run proper premium fuel.

Ok back to the turbo.
What this new compression ratio means is that you should net more HP on low boost than you would with the low compression set up but still run more efficiently when not on boost.
Of course you can't get into high compression and boost and all that jazz without bringing up some type of stand alone ECU.
However, as I have mentioned, I am in CO and can't very well take my truck to Air Care with a Haltech strapped up under the dash.
This leaves us with one option as far as I know. That is a piggy back ECU.
This ECU plugs inline between the stock ECU and the stock harness, grants us a few more tuning options but can be removed easily for emissions checks if you were some kind of lawless hooligan.
Fortunately, for our planet, nothing like this exists on the market and surely never will. (wink, wink if ya know ya know)
I'll just have to live with what I have and run the stock ECU at all times.

For fun tho lets imagine a parallel UNIverse where some kind of CHIP or piggy back tuner exists that lets us tune a few things.
Where could we go from there?
Having not used any of these throretical piggy back units that certainly do not exist I am not sure what the tuning capabilities are... I mean might be.
It is my understanding that a tuned 1FZ lacks a broad enough range in timing control to get too crazy with boost or anything like that especially if we are talking a high comp turbo set up.

Naturally if we are talking about ignition then coil on plug set ups come into play but they are of little use without a stand alone ECU or some way to control them.
I have come across a handful stand alone ignition computers like Electromotive or Performance Electronics I think maybe SDS has a systems that is hard to find on the nets.
While many do grant you better ignition control that could be useful, none state specifically that they will do a coil on plug set up.
Honestly I don't know if all the work and money would be worth if there was a way to get some timing control another simpler way.
My main reason for wanting coil on plug is to ditch the distributor but from my understanding the distributor is still necesary for other inputs for the Stock ECU like engine speed or crank position or something related to that.
Could this be sorted another way. Maybe but again is it worth the time and money? dunno
Sorry I am kind of trailing off at this point and losing my train of thought so maybe now is a good time to stop and we can pick it all back up another day and maybe move on to some other ideas.
 
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For those of you clicking on this thread hoping that I've found the golden ratio to make the 80 Series even better at everything, I appologize.
Alas, I am just posting this in the hopes to get a conversation going about modernizing this rig to take it to the next level.
One could argue that its reliability comes from it's simplicity but there is definitely something to be said about the evolution of the automobile and all of the advancements that have come with it.

I am not going to get too deep into the conversation in this first post.
The fact is I have typed out some long-winded example filled version of this thread at least 3 times now and always delete it becasue I get lost in the sauce (both figuratively and literally (well kinda)
I drink sometimes... What are ya gonna do?

Anyway, the premise is to see what other ideas people have come up with to try to wrangle a bit more of everything out of this rig but there is a catch...
I live in Colorado.
I also live in one of a handful of counties in CO. that require a CARB style emissions check every other year so that is something that I have to think about with every mod to get power or MPG or whatever.
No LS swap for me.

To get things started, allow me jump off with a modern trans swap.
Think 8-10 speeds with much more modern controls.
This was the first... OK technically second (I won't get into that now) idea on my list.
I went so far as to get the transmission before I even had the truck and order up an adapter to make it all work.

I am doing an 8HP70 swap into my rig and from what I gather this offers a significant improvement in both drivability and MPG.
I can also imagine that this could be improved upon with some optomizing to take advantage of the new gear ratios, which I will also get into a bit later.

OK. I am going to stop there.
Feel free to post up any ideas you might have dreamt up and/or ask any queastions you might have on this topic.

I will elaborate on my current plan and toss out some ideas when I am focused enough to do so.

Until next time........
It might not be easy to pass emissions with a transmission swap. You have to be able to perform the drive cycles for the emissions and having a non stock transmission very possibly may interfere with the stock ecm programmed drive cycles. If you have a obd1 truck its probably very doable.
 
It might not be easy to pass emissions with a transmission swap. You have to be able to perform the drive cycles for the emissions and having a non stock transmission very possibly may interfere with the stock ecm programmed drive cycles. If you have a obd1 truck its probably very doable.
well I guess if that happens I'll just do what I should be doing anyway and cheat the system.
Honestly the more I think about all these BS hoops I need to jump through the more I should just stick to my orignal plan then just sell the truck to my mom, register it in her name in her state and drive it anywhere I want without all the hassle.
Whats worse is that everything I originally wanted to do I guarantee would have improved emissions but they won't even test the damn thing.
So instead I drive around in the same gas-guzzling-gross-polluter. How does that make anything better?

What I should do is just buy a 1975 or older truck with title and all that and slap that body on my 80 series chassis, register it as the 1975 truck and never worry about emissions again.
Wait a tick. I might be on to something.
Better yet what about an old van...Hmmmmmmm
 
All the emissions stuff is part of the reason I refuse to move back to the front range, regardless of how much my wife wants to. :rofl: Especially when I have a perfectly running 94 with no EGR or PAIRS.
 
To be clear any electric power steering set up strong enough for this rig is still going to have fluid.
Essentially it will just be an electric hydraulic pump with an attached fluid reservoir.
This unit found in many Volvos seems to be a good option.
I wouldn't bother with any fluid, EPAS from a Prius or Saturn Vue is more than strong enough.

Also, I think it's been documented that electric fans dont pull as much air as the stock fan. I'm a big advocate of going electric (have done it on many vehicles), but on the LC I think I may leave it clutched mechanical, unless there's an OEM solution that moves 3000CFM or whatever it is.
 
I wouldn't bother with any fluid, EPAS from a Prius or Saturn Vue is more than strong enough.

Also, I think it's been documented that electric fans dont pull as much air as the stock fan. I'm a big advocate of going electric (have done it on many vehicles), but on the LC I think I may leave it clutched mechanical, unless there's an OEM solution that moves 3000CFM or whatever it is.
I'm not even going to agree to disagree on this one.
There is no way a column mounted electric power steering system (at least the two mentioned anyway) will work well enough to steer 35s or 37s with a power steering box that is no longer being powered.
I have the Saturn Vue system in my vanagon and I did some considerable beefing of the column, swapped all the rag joints to proper steering U joints and swapped to a manual steering rack so that the ratios would be a bit less stressful on the motor.
Does it work? sure does but its in a 3500lb van with 29 inch tires with a rack an pinion.
I suspect with any real wheeling and sawing the wheel back and forth in a 5500lb rig with 35s the motor would over heat in short order and stop functioning.
Perhaps someone will chime in and prove me wrong.
Not only will I not be mad I will be thrilled becasue I would definitely like to have no fluids to mess with and tuck all that up under the dash.

I also kind of disagree on the electric fan vs clutch fan thing sorta.
I will agree that many rigs work just fine with clutch fans but I can't say that they are better.
The fact that there are so many of the most high performance vehicles on the planet at the most extreme conditions you can dream up running with electric fans is enough to convince me.

I think the majority of times you see an electric fan set up not working is because lil bobbie hill billie decided he wanted to free up some HP in his camaro so he yanks the stock fan and shroud and slaps on the cheapest fan he could find at autozone, likely meant to be usesd as an aux fan, with no shroud what so ever.
Then he is suprised when it's over heating.

Like anything else the advancements in fan tech has lead to better more efficient cooling with better monitoring and control for nearly every situation.

Design is key.
Correct size, numer and CFM and proper ducting/shrouding and you'll be peachy I promise.

Ok I am done whining about emissions for now.
It is what it is and I'm going to deal with it
I don't know how thourough the CO emissions check is compared to other places.
I have never seen them pop a hood.
They slap a thing on to the gas cap to make sure it's working. (I've failed this once)
They check for smoke at the exhaust.
They plug in to the OBDII port so their computer can verify that the ECU and vehicle match.
They check for check engine lights of any sort
Then they chuck it on the rolllers and some dude or dudette) tries his best to follow a green line that represents speed while the sniffer does it's thing.

Thats all I have ever seen them do.
Will my truck pass after the trans swap I dunno
I think I have sorted (well @OutlawMike has sorted) how to remove any check engine lights from the TCU so that should be good as long as the ECU can do its thing and not freak out for some reason then it'll be fine.
If not its on to plan B. It become s "my moms truck" and gets registered in Ohio and I go wild.
OK. Not pollute-the-planet wild but more-efficient wild that will pollute less but be better in nearly every way.

Hmm what else was I going to talk about?

Honestly I have no real plans for a turbo set up.
It's not completely off the table but for now I did plan on making my own free flowing exhaust from the head back and yes I will be running proper CARB legal cats in that exhaust and all the O2 sensors will be very close to their stock locations.

I basically decided I was going to build me a refreshed 1FZ with the compression bump and a free flowing exhaust and one of those piggy back ECUs that definitely does not exist and be happy with that and the 8HP swap.
Don't know what kind of HP nunmbers I might expect from that.... Hmm there is a shop with a dyno right up the street. maybe I should pay for a quick basline run just for fun.

Ok I didn't really talk about too much this round but there are a lot of words up to this point so i'm going to call it for now.

Until next time.
 
A question about more hp, minor increase, and improved consumption.

Would going to a standalone on a stock engine and tuned properly via dyno, improve both hp and give better mpg, small improvements, not thinking a 8 mpg improvement?

I’m lucky don’t have emissions inspection.
 
A question about more hp, minor increase, and improved consumption.

Would going to a standalone on a stock engine and tuned properly via dyno, improve both hp and give better mpg, small improvements, not thinking a 8 mpg improvement?

I’m lucky don’t have emissions inspection.
I feel like there are a couple trains of thought here.
You have the option to increase HP as much as possible with the given components by making the combustion process more efficient so the gain there would be HP and maybe not MPG.
However you could also go the extreme opposite direction by tuning to increase MPG but maybe not HP.
Of course I would like to think there is a happy medium in there somewhere.
So, to make a long story short, which is sort of pointless now that I have already told the long version, yes I believe you can gain some HP and some MPG with tuning alone.
It might be negligible but some is more than zero.

Speaking of emissions I did mine today.
It passed but only just
IMG_20260516_123451.webp

I knew there was a question I wanted to ask the tech while I was there but I could not think of what it was until about 3 minutes after I left.
I wanted to see if the speedo needed to be functional for testing purposes because I will likey have to use a gps speedo for the new drivetrain
Obviously if I am sitting still in a building then the GPS speed would read zero

Speaking of new drivetrain, I did find a long block assembly with a head that I am hoping to go get tomorrow so I can get started on the engine rebuild.
The hope is to have the engine, trans and transfer case all sorted in time for the winter drivetrain swap.
Got to find a decent machine shop and I was thinking it might be cool if I could find a place that does CNC head porting.
Don't know that I would go super crazy with it but I am certain there are some improvements to be had.
I would prefer a CNC set up so the ports are the same but I guess a seasoned tech that has done many ports and a flow bench to check the work would work fine for all that I want to do.

That's all for now. I got some parts searchin to do.
 
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