Trying to gain a few more horse power

[JimC]

Hello out there. We just returned from a 17 state road trip to visit family and friends. It was an awesome trip. I changed out my radiator to an aluminum one with an electric fan before the trip. My reasons for the swap were over heating and hopefully an increase in HP. I also ran a cold air intake. Same reasons. We survived the trip this summer, though some of the grades,( west of Kingman on the 40 for example) had me down to second gear with my eye on the temp. We have a 21’ Sunrader with a 4 speed manual transmission. The reason for this post is I’m considering going to an electric water pump and smog pump to try and take a little more load off the engine. Maybe add a second battery to bank power so as not to put the load on the alternator during a climb. We already have Solar and batteries for the house. Any ideas/advice would be appreciated.

 I am considering mounting an electric motor in such a way as to leave my pumps installed with belt driven by the electric motor with the ability to reconnect to the engine pulley if need be.

[WME]

What engine??

Typically the best thing is to change the rear axle ratio. Search around this site.

[JimC]

Thanks for the reply. I really don’t want to start messing with major stuff like that. I put the one ton rear end in as soon as I bought the motor home. I’m just trying to use all available power the motor has. It’s the 22r. All 4 cylinders have 170 psi on the compression test, so I think it’s in pretty good shape, engine wise.

[extech]

i think you are robbing peter to pay paul.  the energy needed to drive the fans and w.p. and air pump has to come from somewhere, in this case the battery which has to be recharged by the alt.  there is a loss of energy in the exchange.   

  a repacement performance camshaft, header , carb is a better  solution

[linda s]

How long since you adjusted the valves. Makes a huge difference in my rig. Spunkier, better fuel economy. I do mine at least every 2 years. On the 4 banger they get looser so they won't burn but it will not run at optimal performance 

Linda S

[JimC]

I checked the valve adjustment before I left on the trip. They were all good.

[JimC]

I realize that the energy to run the pumps has to come from somewhere. My thinking is the battery is like a bank that the electric motor driving the pumps can draw from while I’m climbing a grade, leaving a few more horse power for the climb. I’m thinking maybe a separate lifepo4 battery that the pump motor draws from that can be isolated during the climb,so the alternator isn’t charging it. Just imagineering. 

[fred heath]

If you only need brief spurts of power, a nitrous oxide system might be the answer. Certainly more economical installation than some of your other suggestions.

 

[WME]

Toyota M/H are to be driven at the "speed of smell". As you learned they are the tortoise of the RV world. BUT you got to where you were going to.

[MaineJed]

We have the most fun during the drive not the destination most times

[JimC]

No argument there!

[JimC]

I’m not worried about being the slowest one out there. When I’m climbing long grades my main concern is heat. I can go faster but she starts heating up, so if I need to drop into second, or even first a time or two to keep out of the red I do. Not much sense in going faster if you blow a gasket. Enjoy the drive. Beautiful country we live in.

[extech]

you may need to check your advance curve. sometimes the mechanical advance gets gummed up.  also use a piston stop to verify tdc on the damper.

 alot of power is often left on the table without having proper ignition advance 

[nicotru]

A weber carb and LCE header will give you the most HP upgrade

[JaySam]

I would second changing out the rear differential to 4.88's. Easily the best bang for the buck. Find a used 3rd member and it's much easier for the mechanic to install vs buying ring and pinion gears and having it assembled/installed. Depending on your year of truck there are a lot of options to pull a 3rd member from. If I remember correctly for my truck it was any 3rd member from 79 - 95 from 4x4 trucks or 4 runners, and some 2 wheel drive 1 ton trucks. Gave a lot of options for pulling from a junkyard or finding used on craigslist/marketplace. Could probably get it done for around $1000. I paid $350 for the third member and $700 for install

 

The axle code I needed was G144 - 8" 4.88 gears 4 pinion 

 

This page can help you identify what diff you currently have and what diff you need to replace it with

 

https://www.lceperformance.com/category-s/23290.htm

 

Otherwise a carb/header upgrade would be the best option

Edited October 19, 2024 by JaySam

[nicotru]

6 hours ago, JaySam said:

I would second changing out the rear differential to 4.88's. Easily the best bang for the buck. Find a used 3rd member and it's much easier for the mechanic to install vs buying ring and pinion gears and having it assembled/installed. Depending on your year of truck there are a lot of options to pull a 3rd member from. If I remember correctly for my truck it was any 3rd member from 79 - 95 from 4x4 trucks or 4 runners, and some 2 wheel drive 1 ton trucks. Gave a lot of options for pulling from a junkyard or finding used on craigslist/marketplace. Could probably get it done for around $1000. I paid $350 for the third member and $700 for install

 

The axle code I needed was G144 - 8" 4.88 gears 4 pinion 

 

This page can help you identify what diff you currently have and what diff you need to replace it with

 

https://www.lceperformance.com/category-s/23290.htm

 

Otherwise a carb/header upgrade would be the best option

Is the 4.88 swap recommended for the 4 speed manual transmission ? my understanding was that it’s recommended for the V6 automatic primarily ?

[JaySam]

I don't know what's recommended for the 4 speed manual but I know 4.88's are what a lot of us have swapped to with the 22re - A43D automatic transmission. You should find out what you currently have and then go from there. 4.56's might be a better option, I think the manual transmission has lower gears than the automatic but I'm not sure. I had 4.10's and the rig was very sluggish so going to 4.56's didn't seem like enough. If you have 3.73's or something like that 4.56's might be a better options than 4.88's. You can find axle to transmission ratio calculators out there to help you determine what the best gearing option would be for your setup. 

[IdahoDoug]

Do you have stock size rear tires?  Are you running a/c on the climbs?  Have you confirmed you are in fact overheating with a manual temp guage installed just to check and compare with the 42 year old factory guage and sender? Check the aged fan clutch?

 

This is a very robust powertrain and if you are overheating I would be double checking things versus doing an electric fan.  The forums are full of people putting electric fans on, not realizing they are downgrading their cooling power.  Replacing an engine-driven fan power for power requires a huge electric fan motor.  I have a lot of experience with powertrains and consider these electric motor fans often a fad-driven interweb thing.  Toyota knew what they were doing in designing the original system.

[thewanderlustking]

I did the 4.88 swap in my old Mini Cruiser after a lot of debate back and forth.  It was the mod that made the BIGGEST difference!  I also did headers and front to back upgraded exhaust.  Getting the timing right also makes a big deal.  The 22 will run with some seriously off timing, but it comes alive(ish) when it is correctly set.  The procedure is a bit weird requiring a jumper and also fiddling with the throttle sensor.  Everyone I have poked at, was done wrong and the timing was off.  

 

I no longer have the Mini, but my best friend Viktor is now its caretaker.  Someday it will get a MegaSquirt (its sitting on my shelf).  But it goes pretty darn good now.  And at least when empty, it does pull nicely all the way up to 70mph.  

[thewanderlustking]

JimC I might get in trouble for opening this can of worms, but DIYAutotune actually has a MegaSquirt that plugs right into your factory harness in place of your stock ECU.  Of course you just say its a 22r...  So if your carborated, this won't apply...  I made my own setup for the Mini Cruiser.  And I am doing it for my 4Runner.    

 

The rear end gear swap actually isn't that bad.  You don't swap the whole axle, you just pull the pumpkin and then have the ring and pinion changed.  These parts aren't expensive either, not sure what you could expect for labor though.  The nicest thing about this mod is that it is in, and done.  No further tuning required.  Just a break in period.