spaugh

I am still running stock everything and the truck runs like a champ with the supercharger. I am NOT going to do any fuel mods. I am debating taking the supercharger off of the tacoma and putting it on my 96 4runner. Any comment on this? I will drive the SC'd tacoma for another few months and then decide if I want to put it on the runner. I am also curious if I need two step cooler plugs or if one step cooler is enough. I don't really hod rod the truck, I just like having the extra power in the hills on the freeway. Also, I don't smash the gas from a standstill for fear of killing my transmission. I only get on it when Im already in 3rd gear at least.

rimpainter.com

Get that EGT gauge in before you conclude to go without fuel mods. And it's not just hot-rodding that's the problem, it's often long inclines while under load that melts pistons.

You're playing with fire.

midiwall

Wow... quite a statement. Okay then.

Any specific reason? Even if you're really & truly not pinging, there's still power to be gained by adding fuel to the fire.


I ran 1-step colder for a year and just switched to 2-step. Doing so has let me throw more timing advance at it without it pinging which nets me a bit more power. But, since you're not doing fuel mods, then I figure you aren't running timing control either, so that's not relevant.


'k... fwiw, the majority of the slipping happens between 1st->2nd. The S/C is well engaged at that point and the driveline is still showing a lot of resistance.

The standing-start-stomp won't really slip since the torque convertor is getting spun up and will catch a lot of that.

A brake torque wouldn't be a good idea though.

spaugh

pure balls


I simply don't think I need any fuel upgrades (Yes I have read all of the fuel mod posts etc). I think being able to retard the timing would be the best upgrade along with the colder spark plugs. I get small pinging when I am around 55-65MPH at low 2000 RPM's going up a steep hill and accelerating just enough that I don't shift out of overdrive. This is the ONLY time I have a problem. And to be honest, I drive up the hill(the same big hill to and from work everyday) at 80-85MPH and zip by everyone on the road with no ping in the 2800-3000 RPM range.

Also, I am considering putting the SC on my 96 runner so throwing more money at the taco willy nilly is not in my best interest. Might wait to put it on the 5spd runner and then invest in the URD kit or maybe just the larger fuel pump. Or maybe I will sell the SC and get a lift kit for the runner? Anyhow, for the short term, I will drive it as it is, enjoy it, and make decision in a few months.

As for the tranny, I am willing to bet that it will be fine for as long as I own it taking into account my driving style and the fact that most failures are 1st/2nd gear. I did install a very large stacked plate transmission cooler in series with the radiator as soon as I got the SC in there hopefully that helps a little.

I do not want to fork out the 500+ for the valve body upgrade or 1000+ for the 7th injector or URD kit. Not to say I would not like to get these upgrades, but just don't think spending another 1500 is in my near future. Also, my truck is under warranty for 100,000 miles, I only have 24,000 on it. I have the platnum warranty until 100k or 2011. If the tranny goes, I will remove the SC and have toyota fix it.

How do fuel mods help with a high EGT reading? Running lean causes excessive heat?

mt_goat

Uh...yeah! I was wondering what part of the melted pistons equation you were missing.

SEAN_at_TLT

So no one has answered my question. Will running two-step colder plugs with out the URD kit be a bad idea? I will get the URD kit very soon but I am getting a major service done next week and want to replace the plugs at that time....

rimpainter.com

^ No Sean, that's a good idea - unless Gadget has changed his stance on colder plugs, but I haven't heard anything about it.

It's also nice that the plugs don't cost much.

(I pulled one of my plugs the other day and it looked great after 9 months or so)

SEAN_at_TLT

sweet, I'll order some from Gadget tomorrow.

spaugh

It would be interesting to hear how many people have melted a piston while driving a SC all by itself. Not too many I suspect.

I just met another guy running his SC with all else stock for the last 3 years. He said he has had no problems to date.

Maybe I am pushing the envelope by running the SC all by itself

I guess only time will tell.

rimpainter.com

You are playing roulette, that's all it comes down to. Gadget knows of a few guys that have melted pistons, etc. Let's put it this way, when and if you run WOT for an extended period of time (since you don't hot rod, let's just say going up a mountain pass or something loaded with gear) your stock fuel system is simply not capable of keeping up with the increased fuel demand. That creates a very lean condition in the combustion chamber, creating insanely high EGT's. Or, there are other times where you might go to pass and starve the fuel system at WOT, causing a spike in EGT's, followed by a sudden loss of power (hitting a wall so to speak), which actually causes EGT's to drop suddenly. All this wreaks havoc on an engine. So, again, you can play with fire or do things safely.

I bought a 97 4Runner with 197K miles on it; 100K of those miles were supercharged with no fuel mods. The guy drove easy, but towed a lot. The thing had a horrendous ping problem when I picked it up in CA. It was so bad in fact, that I was scared to drive it hard back to PHX. I could see and hear the tell tale signs of high EGT's, as parts of the crossover pipe had got so hot that it melted the studs holding the heat shield on to the pipe, thus creating a permanent rattle in the exhaust system. Anyway, that 97 was a testament to the strength of the 5VZ...but I have to ask: Why chance it? We know a fuel-starvation problem exists. So, again, I challenge you, hook up an EGT/pyrometer and see what kind of readings you get.

spaugh

why would you buy a truck in this condition?

How much does an EGT meter cost? Where is the thermometer mounted in the exhaust path? I might just take you up on your challenge and put one on if the price is right.

Also, I just about never go WOT. I don't need too. At half throttle I get all the boost I could ever want.

Can anyone explain how running lean causes a hotter combustion chamber than say an ideal fuel mixture or running rich?

rimpainter.com

Here is my fuel adjustment map. Remember, "0" means it isn't doing anything, +1 means it is trying to fight (or help) the ECU and add fuel when it can - in the ping zones.


And here is my timing map. Again, 0 is "stock" so anything you see on the matrix is an adjustment that had to be made.

spaugh

cool stuff

so how much does the EGT meter run?

rimpainter.com

To scavenge parts and resell it.

Ok, read this since I am by no means an expert on combustion. It might confuse you about EGT's even more. It kind of did me to be honest. EGT's might be highest at lower throttle openings, not necessarily WOT as I have alluded to. Either way, we know there is a problem because a) guys have posted their EGT readings here b) we can hear the HG/LR ping c) power of the engine hits a brick wall when sustained fuel demand is introduced to the equation (without fuel mods). A bent rod might be a bigger concern than a melted piston. It just depends on what you are demanding of the engine at the time I guess.

rimpainter.com

An EGT set up will run $100 - $130. Installation will be more depending on how you do it. I think you can tap the cast iron manifold for the bung and probe, but don't quote me on that. To have a bung welded in place, you are probably looking at 1/2 to 1 hour labor.

spaugh

the link posted is quite a nice post! It states that Detonation will caust EGT to fall??? All seems like a bit of black magic. I am not a mechanical engineer ( I am an electrical engineer) and I bet people could spends their lives analyzing this stuff

Thanks for all the input 96 runner! I will keep this post updated with the state of my truck from time to time and what changes if any I have made to my configuration.

rimpainter.com

Sounds good! Yes, that link is really good. I just read it over. I am going to post it again here:

http://www.germanmotorcars.com/Detonation.htm

HUTCHSTACO

i personlly could not run a s/c without all the necissary mods, i would worry too much

spaugh

there is one thing that you are forgetting, I am under warranty, and I own another vehicle in case of down time.

AND I plan to sell the truck after the warranty goes.

HUTCHSTACO

hey whatever works for you, i just worry about stuff like that, thats why i never supercharged