TDI 1st Gen Tacoma Swap

[jimbote]

this sort of "feeling" can be exteremly tune dependent.... so much at play going on.... but 3000rpm should be a very happy place. at least if tune timing isn't too advanced and other things

That's possible but these are two tunes from "different" tuners. I feel it's more of a mechanical limitation, as far as sustained rpm. My point is, that theres zero reason to shoot for 3k cruising rpm. 2100-2700 is perfectly fine in a relatively light taco. Power is great, I'm not lugging the engine, egts are in check, and still getting low 30s nearly every tank.
EDIT: it's also possible I'm sensitive to secondary harmonics above a certain rpm. Not necessarily damaging, but i have no doubt the motors are "happier" below that threshold.

 

[burpod]

That's possible but these are two tunes from "different" tuners. I feel it's more of a mechanical limitation, as far as sustained rpm. My point is, that theres zero reason to shoot for 3k cruising rpm. 2100-2700 is perfectly fine in a relatively light taco. Power is great, I'm not lugging the engine, egts are in check, and still getting low 30s nearly every tank.
EDIT: it's also possible I'm sensitive to secondary harmonics above a certain rpm. Not necessarily damaging, but i have no doubt the motors are "happier" below that threshold.

Oh yeah totally agree 3000 is a bit much for cruising. My gut would say 2400-2600 would be a nice highway cruising rpm for a heavy truck swap. I think a larger turbo would cruise better at higher rpm

 

[jmodge]

IMG_7127.jpeg

• jmodge
• Jul 5, 2025

last night there, it's hard to leave this place.

 

[jmodge]

Wrong thread, no wonder I didn't remember what I posted here

 

[BimmerTim]

Oh yeah totally agree 3000 is a bit much for cruising. My gut would say 2400-2600 would be a nice highway cruising rpm for a heavy truck swap. I think a larger turbo would cruise better at higher rpm

If I'm that low in RPM at highway speed, 4th or 5th gear, my EGTs are way up. They would sit much closer to 1250 degF. At 3k-ish they are at least 200 degF cooler.

Do you think some of this could be corrected with tuning? I will say that the engine doesn't feel like it really revs nice and smooth. It feels like it's a little labored all of the time. We had talked a little bit about tuning previously, but I'll PM you again to see what that might look like to tune via chips.

I also have a immo defeat 121-pin ecu with a Malone tune for VNT17 and injectors in my toolbox. I really wish I had remembered I had that sitting around when I did the swap to begin with. Maybe I'll start looking into making that change with winter. There are a number of things that would be nice to change/cleanup/update in the harness as is.

 

[jimbote]

Bimmer, it's your tune and/or hardware. My egts are nice and "cool" at low revs. This is today pulling a long moderate grade at 60 in fifth. It did reach a hair over 900 by the top. Yes, my truck is dirty

 

[PickleRick]

The 30 mpg is insane numbers to me. I think my best tank in the 2-3 years of running has been almost 26mpg.

 

[jimbote]

The 30 mpg is insane numbers to me. I think my best tank in the 2-3 years of running has been almost 26mpg.

It's a very clean running truck. Best tank was close to 35 mpg, worst was around 26, and that was towing an fj80 back from the coast (probably shouldn't have done that ). There are other tdi swapped toy trucks that get similar mileage. What exactly is your setup?

 

[jmodge]

Between 32.5 and 36.6 is what mine gets, the latter is consistent with highway driving in moderately flat areas. The former is the worse it's ever gotten including a mix of hauling, off-road, and normal driving. I've never towed a complete tank through it.
The truck is light and the gearing mirrors what is in the Mk4. Heavy flywheel and large clutch, comparatively to stock. Definitely not as quiet and smooth as the Golf and Jettas though.
Smaller turbo and injectors than on Jim's truck.

 

[PickleRick]

It's a very clean running truck. Best tank was close to 35 mpg, worst was around 26, and that was towing an fj80 back from the coast (probably shouldn't have done that ). There are other tdi swapped toy trucks that get similar mileage. What exactly is your setup?

87 4 runner. 285/70/17 mud tires. 2 inch body lift. 2 inch ball joint spacers. OME rear springs and heavy duty shackles. About 4-5 inches of lift all together. All-pro tube winch bumper, 4x innovations sliders, 4x innovations tubular rear bumper with full size swing out spare. 4.30 gearing on the r150. KTT soft top

She's tall and not exactly aerodynamic.

The best fuel mileage I got from the the same Malone stage 2 tune in my DVZ 5 speed Passat was 41-43 mpg on highway road trips. Whether it was running flat ground to Charleston or over the Appalachian to Gatlinburg it got the same hughay fuel mileage. Towing a steel trailer intended for yflyer 18 sailboat packed with 15-17 ft fishing kayaks it would drop to about 32 mpg on the way to the beach

Around town the Passat got a out 34-36 on the same weekly work commute my 4 runner does 24-25mpg on.

 

[jimbote]

87 4 runner. 285/70/17 mud tires. 2 inch body lift. 2 inch ball joint spacers. OME rear springs and heavy duty shackles. About 4-5 inches of lift all together. All-pro tube winch bumper, 4x innovations sliders, 4x innovations tubular rear bumper with full size swing out spare. 4.30 gearing on the r150. KTT soft top

She's tall and not exactly aerodynamic.

The best fuel mileage I got from the the same Malone stage 2 tune in my DVZ 5 speed Passat was 41-43 mpg on highway road trips. Whether it was running flat ground to Charleston or over the Appalachian to Gatlinburg it got the same hughay fuel mileage. Towing a steel trailer intended for yflyer 18 sailboat packed with 15-17 ft fishing kayaks it would drop to about 32 mpg on the way to the beach

Around town the Passat got a out 34-36 on the same weekly work commute my 4 runner does 24-25mpg on.

Yeah. Your mud tires and height are probably hurting. And the tube bumper is not doing aero any favors sounds like an awesome setup though.
I just recently reinstalled my front skid, and i swear I picked up some fractional mpg.

 

[jmodge]

87 4 runner. 285/70/17 mud tires. 2 inch body lift. 2 inch ball joint spacers. OME rear springs and heavy duty shackles. About 4-5 inches of lift all together. All-pro tube winch bumper, 4x innovations sliders, 4x innovations tubular rear bumper with full size swing out spare. 4.30 gearing on the r150. KTT soft top

She's tall and not exactly aerodynamic.

The best fuel mileage I got from the the same Malone stage 2 tune in my DVZ 5 speed Passat was 41-43 mpg on highway road trips. Whether it was running flat ground to Charleston or over the Appalachian to Gatlinburg it got the same hughay fuel mileage. Towing a steel trailer intended for yflyer 18 sailboat packed with 15-17 ft fishing kayaks it would drop to about 32 mpg on the way to the beach

Around town the Passat got a out 34-36 on the same weekly work commute my 4 runner does 24-25mpg on.

You would have to give up some fun to match my fuel economy numbers. I'm pretty much stock as far as stance and lift. Your tires are an inch taller, two inches wider, and about 15 pounds heavier each. Lifts make a big difference.

 

[Braddman]

My EGTs are right around 900°F when cruising at 70MPH in 6th gear at 2200RPM while rolling on 35s. I frequently see 1100°F daily when accelerating. It is also not uncommon to see 1500°F with full throttle pulls. I’m running a BHW with a BV43 turbo and a stage 2 Malone tune with 175HP and 305FT/LB. I get 25MPG on average over the last 5 years and 57,000 miles.

I do find the truck is geared a bit high when I’m running 35s. I like the gear ratio better when I have my 34” winter tires on the truck. I like the BV43 because it has lots of power around 1800RPM. The ideal turbo I think would be a bit bigger than the BV43 because that turbo is limited to 24PSI to 4000RPM then it is dialled back to 20PSI. My truck is mostly smoke free until over 4000RPM. I have a GTB2056 in my BHW Audi A4 and I find the turbo is a bit too laggy. I think a GTB1756 would be the best size for 175HP.

 

[03Golfer]

My EGTs are right around 900°F when cruising at 70MPH in 6th gear at 2200RPM while rolling on 35s. I frequently see 1100°F daily when accelerating. It is also not uncommon to see 1500°F with full throttle pulls. I’m running a BHW with a BV43 turbo and a stage 2 Malone tune with 175HP and 305FT/LB. I get 25MPG on average over the last 5 years and 57,000 miles.

I do find the truck is geared a bit high when I’m running 35s. I like the gear ratio better when I have my 34” winter tires on the truck. I like the BV43 because it has lots of power around 1800RPM. The ideal turbo I think would be a bit bigger than the BV43 because that turbo is limited to 24PSI to 4000RPM then it is dialled back to 20PSI. My truck is mostly smoke free until over 4000RPM. I have a GTB2056 in my BHW Audi A4 and I find the turbo is a bit too laggy. I think a GTB1756 would be the best size for 175HP.

What is your gear ratio?

 

[Braddman]

What is your gear ratio?

The diff gear ratio on my Tacoma is 3.73. 5th gear is 1.00 and 6th gear is 0.89.

 

[PradoTDI]

If I'm that low in RPM at highway speed, 4th or 5th gear, my EGTs are way up. They would sit much closer to 1250 degF. At 3k-ish they are at least 200 degF cooler.

Do you think some of this could be corrected with tuning? I will say that the engine doesn't feel like it really revs nice and smooth. It feels like it's a little labored all of the time. We had talked a little bit about tuning previously, but I'll PM you again to see what that might look like to tune via chips.

I also have a immo defeat 121-pin ecu with a Malone tune for VNT17 and injectors in my toolbox. I really wish I had remembered I had that sitting around when I did the swap to begin with. Maybe I'll start looking into making that change with winter. There are a number of things that would be nice to change/cleanup/update in the harness as is.

Based on what I've experienced with a tune from Burpod, it will definitely make a difference. I had a Malone Stage 4 previously, the engine now runs better, starts better, revs smoother, builds boost smoother, holds it longer and higher, and runs about 100-200ºF cooler at speed. EGT's take a lot longer to climb to the same levels as before under heavy throttle.

 

[PradoTDI]

My EGTs are right around 900°F when cruising at 70MPH in 6th gear at 2200RPM while rolling on 35s. I frequently see 1100°F daily when accelerating. It is also not uncommon to see 1500°F with full throttle pulls. I’m running a BHW with a BV43 turbo and a stage 2 Malone tune with 175HP and 305FT/LB. I get 25MPG on average over the last 5 years and 57,000 miles.

I do find the truck is geared a bit high when I’m running 35s. I like the gear ratio better when I have my 34” winter tires on the truck. I like the BV43 because it has lots of power around 1800RPM. The ideal turbo I think would be a bit bigger than the BV43 because that turbo is limited to 24PSI to 4000RPM then it is dialled back to 20PSI. My truck is mostly smoke free until over 4000RPM. I have a GTB2056 in my BHW Audi A4 and I find the turbo is a bit too laggy. I think a GTB1756 would be the best size for 175HP.

This sounds pretty similar to my experience. My EGT's and rpm's are a bit higher at 70, and I get slightly worse fuel economy: avg 23.5mpg over 45k miles. I have smaller tires, but likely a heavier vehicle and definitely worse aerodynamics. Normal running weight is around 4800-5000lbs for me according to a local weigh bridge, loaded for a weekend camping trip with a couple of people is probably pushing 6k.

 

[PickleRick]

As soon as Burpod has confirmation he can get the cruise control functional on the tune I'm also going to throw some cash his way. I'm hoping he can also squeeze out a few more mpg for me.

I never thought I'd need this much lift but the morning of Helene I'm glad both the yota and the disco had their lift kits. They got us to work by about 630 am, a half hour drive under normal circumstances. The storm was still a cat 1 as it was passing and we were out at about its peak. There were several places were standing water was half way up to our doors and more than a few limbs we had to drive over. Unfortunately in our lines of work we get really busy when those kind of catastrophic storms hit, I'm still selling/repairing equipment that is cleaning up western NC and our local areas. We still have local bridges out from it.

 

[dieseldonato]

I've driven this truck for over 14 years, so I have a very good feel for what happy cruising rippums are. 3k is not it. Sure, it'll do it, but it doesn't like it. I keep it under 2800 cruising most of the time, which is plenty fast.
Same goes fpr my AHU swapped westy. 3k is not fun. It also likes 2800 and below. All i can say is that I know my machines.

Vw had plenty of "industrail" engines that were basically the same engines we have in our cars(trucks in your case) that would sit at 3k + rpm and live long happy lives. Not to meantion the watercraft side of things. Recall someone on this site, years ago, swapping a tdi into a jet drive. 3100 rpm for 4 hour trip up in Canada somewhere. I believe he had over 1k hrs on his swap at that point. His engine was tuned as well from what I recall too.
Anyway, point being, the engine is not running beyond its design capabilities. I cant speak to your specific set up, or why you feel its unhappy at 3k rpm and fine at 2800 rpm.

 

[jimbote]

Vw had plenty of "industrail" engines that were basically the same engines we have in our cars(trucks in your case) that would sit at 3k + rpm and live long happy lives. Not to meantion the watercraft side of things. Recall someone on this site, years ago, swapping a tdi into a jet drive. 3100 rpm for 4 hour trip up in Canada somewhere. I believe he had over 1k hrs on his swap at that point. His engine was tuned as well from what I recall too.
Anyway, point being, the engine is not running beyond its design capabilities. I cant speak to your specific set up, or why you feel its unhappy at 3k rpm and fine at 2800 rpm.

I do understand that many "industrial" or marine applications run at higher rpm. My truck is neither a boat or a generator. VW does NOT engineer their cars to run at 3k rpm cruising. If it was an ideal operating rpm for passenger comfort, plus FE/longevity/emissions, I'm sure every tdi off the assembly line would be geared like a mid eighties gasser. They're not. My truck loves cruising between 2k and 2.7 k. If it was comfortable, and felt right at 3k, I would just blast the down highway in fourth.
I don't believe it's damaging to run at higher rpm, just doesnt feel "happy". And if you don't understand that "feeling" yourself, I don't think it can be quantified with charts or math to elicit that understanding.

 

[dieseldonato]

I quite understand that "happy engine" feeling. I've worked on a lot of diesel engines and rebuilt quite a lot too. Doesn't take long to ascertain what its happiest at. Im simply saying, its not going to blow up, nor are you hurting it at 3k rpm.

 

[jimbote]

I quite understand that "happy engine" feeling. I've worked on a lot of diesel engines and rebuilt quite a lot too. Doesn't take long to ascertain what its happiest at. Im simply saying, its not going to blow up, nor are you hurting it at 3k rpm.

Quoting my previous response: "I don't believe it's damaging to run at higher rpm..."

 

[PradoTDI]

It seems to vary from engine to engine. I’ve run a 400k mile ALH for hours at 3k rpm on the highway, it is smooth as can be and doesn’t seem to have much effect on fuel economy. The one in my LandCruiser seems to get buzzy at that point, feels happier at or below 2800 but that could also be due to how it is mounted. The new tune from Burpod definitely helped with that. Both my AHU’s started to feel buzzy at 3k also, but my parent’s BEW is happy to rev to 4k.

 

[burpod]

It seems to vary from engine to engine. I’ve run a 400k mile ALH for hours at 3k rpm on the highway, it is smooth as can be and doesn’t seem to have much effect on fuel economy. The one in my LandCruiser seems to get buzzy at that point, feels happier at or below 2800 but that could also be due to how it is mounted. The new tune from Burpod definitely helped with that. Both my AHU’s started to feel buzzy at 3k also, but my parent’s BEW is happy to rev to 4k.

not so sure its the actual engine. most likely its due to things like axles, various mounts/bushings, tires, joints, etc, and the tune can play a huge factor in it all as well, combined with all the other hardware modifications like turbo/pump/injectors. it can really take some effort to dial in a tune for a specific hardware combo in to get it feeling 100% happy everywhere. and thats without all the various little hardware things that can be wrong and not noticed

 

[BimmerTim]

For fun, on my way back to MN across Wisconsin today I ran 5th gear the whole way. Basically at 2250 rpm the whole time. The EGTs sat between 1150-1450 degF the whole time, with the exception of downhill. I didn't love the EGTs, but it was for science...

With only one data point in each direction I can't possibly say that one is better than the other in terms of mpg, but I got 27.4mpg on the way there and 26.6mpg on the way back. Each direction is almost exactly one full tank of fuel, though.

 

[burpod]

For fun, on my way back to MN across Wisconsin today I ran 5th gear the whole way. Basically at 2250 rpm the whole time. The EGTs sat between 1150-1450 degF the whole time, with the exception of downhill. I didn't love the EGTs, but it was for science...

With only one data point in each direction I can't possibly say that one is better than the other in terms of mpg, but I got 27.4mpg on the way there and 26.6mpg on the way back. Each direction is almost exactly one full tank of fuel, though.

those kinds of egt for cruising... sound... painful

 

[BimmerTim]

those kinds of egt for cruising... sound... painful

It hurt my soul. But I'm a man of science.

 

[jimbote]

It hurt my soul. But I'm a man of science.

Years ago, after i first built my truck, i had Jeff tune a spare ecm at one of Dan's GTGs. Popped it in and holy moly! That was a smog belching, egt pegging tune. Needless to say, it got swapped out immediately for the ride back home. Not long afterward, I became a dealer for TDtuning, so that's what's been in there for the duration, and it's been pretty good. But I'm sure Burpod could make some improvements.

 

[BimmerTim]

Do we worry about air/water separation other than the stock filter or prefiltration? Not that I need to add more things to the plate, but I'm already looking at installing a late mk4 in-tank pump into the Tacoma tank. Soooo, while I'm in there...

 

[BimmerTim]

I also started prepping for to swap over to a 121-pin ecu. I won't actually do it for a while, but I wanted to see what would be involved. It's so close I feel like I could almost make an adapter. I ran to the Upull yard and was able to snag an ECU from a manual 03 Beetle tdi and the ECU pigtails. And some misc stuff for the Tacoma.