Project 7MGTE, R151F, Dual Marlin Swap

Started 12/2/00
Finished 02/15/01

Update 04/21/04
Well, I am getting married this Saturday, it will be April 24th 2004. I tore my 4runner apart last summer to get ready to get married. Eventually I will build it back up again with a 600HP 2JZ. I already have all the components, now I just need the time. I will be going automatic too. I just broke too many parts with the manual. I will also be going 35 spline 60 in the rear, or a 14bolt, and I will probably do a divorced t-case with a 2wd auto. I do not need a dual t-case with an auto, just a 4.7 gear. I miss driving the 4runner, but it will be resurrected some day.
Update 05/12/03
Well, Statesville ended up being a flop. It is amazing how decieving people can be, even when they say they are your friends. Ended up losing around $8,000 in the 2 months I was out in North Carolina, in lost income and moving expenses. Oh well, learning experience. While I was out in NC, I did accomplish to get myself into doing another 7MGTE conversion in a 2wd pickup. Click HERE for more info. The trip home was fun though. Picked up a 89 supra while I was out there, stuck it on a dolly and towed it back.
Update 11/29/02
I am now out in Statesville North Carolina. Don't know exactly what I am going to do here yet, but I will find out soon enough. Truck held up great for the 3,000 mile journey. Hauled a trailer full of parts, the first half, and the other half, a tow dolly with a supra on it, with lots of parts inside. Very heavy load, but averaged 70-75 mph and 10 mph. Not too bad considering the heavy load. Got some wierd looks as I would pass up Chevy, Ford and Dodge diesels.

Update 10/09/02
Holy crap, been almost a year since my last update. Guess I have been having too much fun with this thing. I now have over 20,000 miles on my 7MGTE swap, and it is still going strong. I have broken about everything except the motor and the two transfercases. I am surprised how well the stock transfercases have held up. I was sure they would be the first to go. Earlier in march, I broke the shifter fork on my R151F so I pulled it out and put in a W56 until I could get the R151F fixed. Well I drove on that for about 4 months until I sheared off the output shaft. Then I ran a G52 for about 2 weeks before I roasted off 1st gear. Well I finally go my R151F fixed and it is back in. Although I didn't get rebuild it like I wanted too.

I have gone through over $1,500 in driveslines, and finally found out that saginaw CV shafts suck, so I replaced them with toyota cv's and havn't had a problem since. I have broke a rear joint on the driveshaft, but replaced it with a hug 1410 or something like that, and havn't broken that, even with binding it on many occasion. I have taken out front hubs, and front joints, but that won't be solved until I go D60 in front, so I will just be carfull with that and bring spare parts. I have broken 5 rear axle shafts, and a set of spider gears.

I have made several modifications to the intake and exhaust. My exhaust runs straight back instead of crossing over under the oil pan. My intake is 3" only using mandrel bends. And I run a 2001 Ford Powerstroke intercooler. Man, what a difference the 3" and the big intercooler made. Full boost dropped from 4500RPM's to 3,000 RPMS. I used to get very sparatic boost levels, and now it boosts the same everytime. Recently I took my rig to the drag strip. Unfortunatly the new clutch I had just put in was a defect, and I could not run more than 5 psi, and I run 12 psi on a daily basis. Anyway, with a bad clutch, I ran a 17.9 at 75 MPH, I should be able to run a mid 15 at 90-95 MPH with a good clutch.

All in all, I could not be happier with this swap.
Update 10/23/01
Finally got my Dana 60 rear and Dana 44 front complete. I have been running around for a couple months with increasing the boost, and no broken rears. Don't know how well the driveshaft is going to hold up though. I have reworked the cooling, and intake piping a little. Got rid of my real coils and went to 56" long all-pro springs. Oh, and I didn't move to NC, still here in Utah.

Update 5/15/01
Well, truck has been down for about a month now, I kept blowing out rear ends. Truck still runs great, lots of power too much power for everything else. The truck has been down because I am redoing the suspesion. Leaf in the rear with 65" wide Dana 60's front and rear. I am getting close to done, but I will be moving to North Carolina before it is complete. There I will finish with the suspension, and at the same time working on an intercooler system and and building a race motor. I was concerned about the bellhousing so I ran it hard with minimal support to see if I could break it. Seems to be holding up great, so with support, I shouldn't have a problem. I did manage to put hole in radiator and had to close off 6 passage ways on the stock v6 radiator. At full thottle in the mud on a warm day I stared heating up a little, but then would cool right back down. Later I will build a custom 4 core radiator that will fit under the hood support so I can run my fans on the inside to leave room for my A/C.

Update 02/21/01
Well, all done. Finished up on the 15th. 15 days after origanal date. Oh well. So far I have put over 500 miles on motor, and it is still running strong. I really enjoy that extra power. Now I need more.

Why the swap?

The Toyota 3.0V6, is my no means a powerplant at 150hp , and there is not a lot you can do to increase power without it costing thousands of dollars. After running 35x14.50's for a few months, terrible gas mileage, and not being able to cruise at freeway speeds I was fed up with the lack power.

I had been looking into engine conversions for quite awhile, and have heard several people putting the Toyota 3.4 v6, Chevy 4.3 v6, or a V8. I wanted a little more power than the V6 could put out, but didn't like the idea of breaking everything because of the low end torque and horsepower that the V8 put out. I have been big into toyota Supras for awhile and really like the power of the inline 3.0 6 cylinder, and it perfect for what I want. I want power, and lots of it, but I don't want to break anything because of that. With the Turbo Supra motor, there is defianlty not a lack of power. A slightly moded 7MGTE motor will yield over 500hp, and still get 26 mpg. But, a drawback of the turbo, is very little low end power, and turbo lag. This is what I want. I really don't want lots of low end power, that is where things get broken. This set up will be perfect. The transmission I first chose was the 30-40LE,also known as the A340F with the manual shifting transfercase. The transmission I had uses a hydraulic actuated transfercase which uses a chain driven transfercase that cannot be detached from the transmission. I wanted to use a gear driven transfercase so I could use Marlin Crawlers dual transfer setup. This changed shortly after I could not find an A340F, and that they would not be able to hold up to kind of power I was going to be running. I then decided to use the transmission out of the supra, the R154. The R154 is the same transmission used in the V6 manual trucks, R150F with a different ouputshaft and tailhousing to bolt up the transfercase. The problem with the R150F, is that I would have to buy an adapter to be able to use the gear driven transfercase. The R151F is used in the turbo trucks. Same transmission, different gears different tailhousing. This tailhousing had the gear driven transfercase already attached. So, I picked up an R151F. The R151F has 3 features that are very desirable for most toyota rock crawlers. 1. Tailhousing for gear driven transfer. 2. Used with 23 spline transfercase, much stronger than the 21 spline. 3. Gearing. With the 4.31 1st gear vs the 3.83 of the R150, the R151F is a much better tranny for rock crawling.

Now to begin the swap.
Checking clearence on swap
As I begin to figure out what bolts to what in order to get this up in running, I run into some problems. Being an I6 motor, it is several inches longer than the V6. There is limited space for the engine in the engine bay. For cooling. There is only about 3 inches between the motor and the radiator. I could cut out the firewall to make room, but there is too much stuff on the other side that will have to be moved out of the way for that. For now, I will just remove the condenser until I find a suitable place for it.

Here is a partslist I put together. Parts may vary in prices depending on what good deals you can find, used vs new, quality, and stuff you may already have laying around. This will give you quick rundown of all the parts needed, and estimated price.
Parts list for Swap
Modified bell housing

This can be very simple, or very difficult. Depending on the power that one would run. Because I plan on heavily modifying the engine, I chose to run an R-Series transmission. I could run a G-series transmission, but I don't think they would hold more than 400hp. The G-series or W-series transmission will bolt right up to the engine with NO MODIFICATIONS NECCISARY, you just have to the bellhousing from 79-92 non-turbo supra.

Updated tranny info 05/14/01
In using a G52 or a W56 transmission, here is what needs to be done. For example, I can bolt up a G52 or a W56 withouth any special adapters, couplers clutches, flywheels. Get the bellhousing and flywheel from a 79-92 non-turbo supra. This bellhousing will bolt directly to a 7MGE or 7MGTE. use the clutch assembly from the same vehicle 79-92 non-turbo supra. This is all you need. You can now bolt up your G52 or W56 or alike transmission without any problems.
Special thanks to CAZ who was the first to do an article on the Supra 5M swap Now you would just have to fit it in your truck

what the Bellhousing/tranny application guide

There are 3 types of R-series trannsmissions though, the R150F(V6), R151F(Turbo Truck), and the R154(87-92 Turbo Supra). I plan to use the R151F. The problem, is that Toyota never designed an R151F to bolt up to the 7M block. As I compare the R154 and the R151, I notice that they are not the same transmission. They use a different input shaft, different bellhousing, and different output shaft. John Douglas has given me some very good pointers on what I can do here. The input shaft on the R154 is longer than the R151F, and would not work with the bellhousing off the supra, the bellhousing is also longer. I thought I could change the input shaft, but come to find out, that is not possible either. I could change output shaft on R154 to the shorteri R151, but this requires a complete teardown of transmission, and I would get the first gear ratio of 3.25, instead of the sought after 4.31 of the R151F. In wanting to keep the gears of the R151F, I decided to modify my bellhousing to bolt the R151F to the 7MGTE. For the modification, I am taking half of the R151 bellhousing and welding it to the other half of the R154 bellhousing and shortening the bellhousing at the same time.

The clutch peddle assembly was pretty easy. Being that my truck was an auto, I had to install a clutch pedal and master cylinder. All pretty easy. I used a 2" hole saw, and drill for drilling the holes. In the 3rd generation trucks, and 2nd generation 4runners, parts of the bracket for the clutch pedal are missing, so it is easier to use the assembly from a manual truck or 4runner, and replace the stock assembly. I used the assembly from a 1990 manual truck, fitting nicely with no extra mods. I ran a piece of hard line under the brake booster, over the top of the motor, and down to the clutch where I used a piece of flex line to go from the hard line to the slave cylinder. With the modifed bellhousing, I was still able to use the stock clutch fork and throughout bearing for teh R151F.

I used the flywheel, pressure plate, and clutch used for a 1985 for the 5M. Toyota also used similar components for the N/A supra from 1987 to 1998, V6 trucks, turbo trucks, and other later model cars not using the 22R. For the actual clutch disk, I am using a custome 4 puck clutch.

Engine Mount

Mounting Hardware
The engine mounts used were from 7M. Unlike the 5M, and 22R mounts that had a flat surface with two flanges on the sides and holes for bolts, the 7M use a single bolt. The frame mounts have slots for this bolt to slide into, and a nut is put on from the back side. I did have to design my own engine frame mounts, but that was pretty easy. I made them from 3/8 steel, so, strength is not an issue. The stock rear crossmember was not even close to lining up so scrap that. In looking for other options, I saw the rear crossmember from Front Range Off Road. With this crossmember, it makes it much easer to possition the trasfer where I want, weld two brackets on the side, and done. Too easy. With this crossmember, I was also able to raise my drivetrain a bit. I did have to cut out my horseshoe collar and move it up, but not to complicated.

Updated mounting info 05/14/01
The mounts I made are for a v6 to 7M swap. If I had a 22R, the mounts are in different locations on the frame, and I would have the option of keeping the stock mounts. If the stock mounts are kept, you can bolt the 7M to these mounts, but there are a couple things you must do. The 7M mounting brackets bolt to the center of the engine. That may or may not be too far back for the stock frame mounts. If so, the mount brackets on the engine may be moved forward(5M engine mount brackets from 85-older supra may be required to move forward). If that is done, the oil filter plate, must be rotated to make room for the bracket. Use the rubber mounts from the old 22R and bolt those to the engine brackets. Engine should go right in as long as there aren't clearance issues with firewall, egr valve, and brake booster.

Wanting to have A/C, I decided to cut out my front radiator support, yes that includes the hood latch. I just now use hood pins to hold down the hood. I am using the Supra radiator for cooling now, and it works great. I welded bushings on the front crossbar for the radiator pegs to go into, and made mounting straps for the top. I then mounted two 1200 CFM fans to pull through need. So far I stay below 200 degrees, even on hot days at full throttle and boost.

A custom 3" exhaust was made with a high flow cat, and flowmaster 3 chamber muffler(I wanted it to be quite unlike my cars running a single chamber). There was a little problem with the exhaust system, but, there is a way around everything. The exhaust on the 7M drops down from the passanger side. Well, this is where the the driveline is. I could not run the 3" pipe straight back. And, I could not cross over under the transmission, for sure it would get smashed. But, there was a nice little gap between the oil pan and the transmission, and the exhaust seems to route nicely though there, then all the way back.
------Exhaust Update----------
I was able to run the exhaust down and directly back. I did have to relocate the gas tank, but with that, I get more direct flow and lets bends.

The 7MGTE requires about 30-40 psi in the fuel rail in order to deliver enough fuel. By looking at the size of the V6 fuel pump, and the 7MGTE fuel pump, I don't think it will do the job. I removed the pump from an 87 Supra Turbo, and fit it to the V6 fuel tank. Not a perfect fit, but it works great. The 7MGTE pump is a much lager one. This will make sure I get the proper fuel flow and pressure. The turbo's are very picky about that. The stock fuel lines run along the passanger side of the truck on the inside of the frame rail. This is good except that the fuel would have to pass directly next to the turbo. Not wanting this, I had to run the lines over to the drivers side. This is the side the exhaust comes down, but by then the exhaust is much cooler and shouldn't be a problem.

Power Steering
I am using the pump and reservoir that comes with the supra. I was acutally able to use the stock lines that connected to the ABS box on the right frame rail. No special adapter or hoses, connected with only an adjustment with a tube bender.

Front and rear drivelines have CV. Rear drivline had to be shortened. Front driveline is custom long travel.

Well, unfortunalty, I had to remove the A/C, but only temporary. I will get the A/C working. I have plans to put the condensor back close to the original location. May need to be moved forwad slightly, but shouldn't interfere with much.

After 3 intercoolers, I finally have one that works. It is a little big, but heh, it is almost too efficient. It is out of a 2001 Ford PowerStroke, and the thing is massive. Because the pipmes coming off the IC were 3", I decided to go 3" piping for the entire intake. I will probably to some testing with some smaller pipes, but for now, the 3" works awesome. I always here about how laggy the CT-26 turbo is when upgraded with the 60-1 compressor. Full spool usually doesn't come until almost 4,000 RPM. With my old piping and IC's, that is exactly right. I got a nice boost of power at 4,000 RPM, but nothing before. Now, full boost at 2,500, and hardly any lag. It is amazing. I can now break traction when I hit full boost and around 4,000 RPM running 35" tires. Quite a rush I tell you. Pictures

Diagram of 7MGTE ecu and harness

The wiring of a 7MGTE is a lot easier than most people think. In fact, it is very easy. I will use almost the complete harness, toyota was nice enough to only put mostly engine related stuff into the harness. All I had to do is connect power to the ecu, and run some gauges off of it. The stock V6 alternator will bolt right to the motor, no mods necessary although I chose to run a supra alternator just had to change connectors.(reason is I have a shelf full of good supra alternators, and one v6 alternator that went bad). The starter harness is built into the main engine harness, same with the v6 engine, so I just had to splice in. Took all about 5 minutes. Fuel pump is run off igintion switch, but will later be run through a dual voltage relay like it should be.

Here is a more detailed descrption of how to wire up a 7M motor Wiring

Click installation for next page.

back to home page
Other Projects
email me at for any comments or questions

Finally finished. Took me long enought, but I got it done. So far I have about 500 miles on it, and no problems. Damn this thing no has a lot of power. I will post pics later.