Engine/Transmission (1998.5 - 2002) High EGTs

[PhilJohnson]

Hi guys, I need some help. I recently bought a 25' toyhauler and have been doing some upgrades to help pull it. The trailer wieghs probably 6500-7000 loaded. I have an 01 auto with 3. 54s, 35in tires, Goerend TC and VB 4" ex, fuel, egt and boost guages and Super Tuner set on high. Air filter is stock. It seems like it should have more power and sees 1400 degress with ease on almost any slope unless I back way off. I know it has the small turbo. If I go larger on the tubo and maybe 80 horse injectors will that cure the problem?What size tubo? Thanks.

 

[nps]

Check the intercooler hoses for boost leaks. The driver's side rubs on the fender sheet metal, and the pass side rubs on the A/C pressure switch.



Make sure you are tight and power will go up/EGTs down.

 

[Graphic man]

A BHAF will help a little

IMO a b1-2 turbo and 1. 5 inj

what kind of boost are you seeing?

 

[PhilJohnson]

Thanks for the response. Boost does seem a little low, maybe 18 lbs max. I was going to pull over and remove the air filter for a short distance to see if it made any difference but the dust was blowing pretty good. I will check the boots today. thanks again for the help. I have a long over due vacation coming up and I don't want to pull the trailer watching the pryo guage every second.

 

[rkressg]

18psi is about right for the HY35 in your truck. I think the problem is you are working the engine very had with oversized tires, auto and 3. 54 gears. Try driving in a lower gear (take out of OD). Also, of course check for loose intercooler boots/leaks. You might want to consider better air intake (filter), bigger exhaust, and a larger turbo. Also, a gear change (to 4:10) would greatly help with towing, but this is expensive.

-Rich

 

[blacksheepdiesel]

Get the boost elbow from TST; that and rv275's increasedmy HO 6spd to 29lbs boost.



Trent

 

[PC12Driver]

The boost elbow won't work on his turbo, since the HY's don't have an elbow to replace. TST does have a "J hook" (as do other vendors) that allow more boost from a HY. That'll get you well into the 20's as far as boost, and that should bring your temps back down.



There's no need to put on a bigger turbo if your temps are in check. You'll only gain lag.

 

[PhilJohnson]

Hey PC12. What if I did the turnbuckle on the waste gate? would the computer start defueling? I have a Super Chips tuner and I don't think it has a boost fooler. Also you don't think a larger turbo would help. Thanks again for the help.

 

[boondock]

What PC was saying with your turbo and Super chips tuner is that you don't have enough fuel for a bigger turbo. Do a search for . 22 shell do block the WG to get your boost up. That should solve your egt problems for the time being or help out a great deal.



Also consider selling the SCT and putting a edge comp in and don't pierce the wire till you want need more power. So you will have have a edge ez and be adjustable in the cab and have a boost fooler. EGT's will stay in check with the edge ez.

 

[PC12Driver]

That's true, you do need some form of a boost fooler to prevent defueling. There are stand-alone boost foolers on the market (about $150 I think), but maybe boondock has the right idea with swapping the tuner for a box that has the foolin' built in.



When you change turbos the truck's powerband and responsiveness are changed. It's a trade off; you take from the bottom and add to the top. The common thought that you see a lot here on the TDR is that you can make up for a laggy turbo by adding more fuel (injectors, box, etc. ). That's true to a point. Under full throttle operation the extra fuel will generate more exhaust gasses than a stock engine would, and the greater volume of gasses can drive the bigger turbos. So the only time "extra fuel" will help spool the turbo is when you're using it, i. e. full or nearly full throttle. During partial throttle applications you're not flowing any more fuel than you would have been when the truck was stock, so there's no extra exhaust gasses to drive the bigger turbo, so now you have more lag.



I put a bigger turbo on my truck because I though I had enough fuel to drive it. It ran great empty and kept the full throttle egt's in check, but when I put the trailer on I got the lag that I mentioned above. Slight hills wouldn't be enough to cause enough load on the engine to use the extra fuel to light the turbo, so I'd end up with less boost than the stock smaller turbo would produce, and hot egts. The bigger turbo made my truck a towing pig below 1900 rpm or so. I had to be really light on the throttle or downshift. Now when I tow, I put my stock turbo back on and I got my low-midrange performance back. I can leave the truck in 6th with the cruise on and the little turbo would generate much more boost at lower rpm's than the big one, and the extra boost keeps the egt's in check.



So that's why I wouldn't reccomend a bigger turbo at this point. If you get your boost into the mid 20's I think your egts will be back under control. The little HY should be good for almost 30 psi, so you're not even using all of its cooling potential yet. If you do end up with 80hp injectors, something slightly bigger would be the way to go. Like a PDR35/12, or even a take-off from a manual truck (which can probably be bought for a couple hundred bucks). My stock turbo (HX35/12) was enough to keep my Mach 2's and an EZ under 1250*. Just don't be tempted by the "bigger is better" concept with turbos; you can really screw up a great running truck if you go too big too quick.

 

[PhilJohnson]

Thanks for the wealth of information. I will probably go with an Edge E-Z and see if it lowers my EGTs. I didn't really want to spend the money for the turbo and injectors right now any way. Don't think I can sell the Super Chips as it is VIN locked and won't work on a different computer. I can still use it to calibrate the tire size and for trouble codes. All I'm really looking for is drivability when towing and enough power to keep up with the newer stock Chevys and Fords my friends have. Does anybody know a good place to buy Edge products?

 

[Fishin Guide]

Just a quick opinion on my original setup for you.



My truck is an '02 with the auto, I had the HY and 3. 54's and I did have a 4. 5" lift with 315's.



All stock, the truck would run very hot when pulling any kind of weight. Adding the an EZ with a hardware store turnbuckle dropped my temps a significant amout. Then I tried removing the hook. To my surprise, the EGTs didn't go as ballistic as I assumed they would.



So, you may gain some relief just from the added timing of the EZ. BTW, when I switched to the DDUFM, my EGTs went up a few degrees, but I had a lot less rattle.



The bottom line is you are taxing you engine far more with the tire height and gear ratio than it was intended to run. Adding power will help, but that will lead to all the other things you may or may not want to do.



I have been happy with the stock size tire/ 3. 54 ratio and the rest of my setup to get me to the 388HP mark (no pump wire) and a used PDR35-12. I will outgrow it when I tap the wire, but you would be surprised how far the little turbos can take you.



Dave

 

[PhilJohnson]

I'm confused. Talked to my vendor today about the Edge Comp. He told me the Comp would add higher Egts than the EZ. He also said either one would run hotter than the Super Chips I'm running now. I have the 4" exhaust and drilled air box and getting the BHAF. He suggested methonol or whatever to lower my temps. I do have 315s with 3. 54s but at the same RPM shouldn't a truck with lower gears or smaller tires be about the same. My truck will hit 1400 up hill empty, no problem, 18 lbs boost. Isn't methonol a little extreme for stock with a 65 HP tuner? If a larger turbo gives me more lag thats no good either, cause I have plenty already when pulling. My goal was to go maybe 400HP but I don't see the point in Bombing if I can't use the power and the stock power is not enough to pull my 6000lb trailer without getting passed by everything on the road. Excuse me if I sound frustrated but I am. Thanks for the help so far.

 

[PC12Driver]

That's halfway correct. Level 1 on the Comp is the same as the EZ, so on that setting, temps will be the same. Levels 2 through 5 will be hotter on the Comp since the box is forcing the fuel pump to feed more fuel via the wire tap. With the Comp you also have the advantage of adjusting your rate of fueling (smoke level) in the cab, or turn the box off altogether (the boost fooler circut stays in place).



I'd bet that an EZ or Comp (on level 1) with the turbo properly wastegated (J-Hook installed) will run cooler than the Superchips thingy. The 'Chips and the EZ both add about the same power, but if you get the boost up the temps will come down. Think of it this way; the stock truck would hit 1250* and you added more fuel without adding air (still 18psi). More fuel=more egt, so of course the temps are gonna be hotter. The only way to cool it is to add more air. The airbox mods and the exhaust may help slightly, but they're not the limiting factor at your power level; the low boost level is!



The EZ/J-hook combo is a sure thing to get the temps down and add power. And your existing mods will complement the combo nicely. And when you outgrow that, add some Mach 1. 5 or 2 injectors and something like a PDR35/12 (keeping with the more fuel/more air theme) and you'll have a very responsive, really fun 350hp/750tq truck that you can tow all day with and not worry about the temps.



And yes, the water injection is a bit much at this stage of the game IMO.

 

[PhilJohnson]

Thanks PC12. I will try it. The Comp and EZ are about $125 difference, which one would you go with? Can I use a turnbuckle and keep the wastegate closed all the time? One last thing. Do you know where to get the heat shield for the BHAF? Sure appreciate the help.