20V Blacktop Swap – Miscellaneous Info

Here’s a summary of the smaller things that you will need to do that aren’t big enough for their own page:

Fuel line

Contrary to what was previously on this page, the 16V fuel line fits fine with no modifications (both SC & NA). I mistakenly used the 20V line which needed to be extended. Sorry about that.

Throttle Cable

For neatness this needs to be extended a couple feet. If not, the cable will have to drape over the engine. I combined the MR2 cable with that of the 20V.

Here’s the steps and pics:

– Cut the ends of each off with pliers, being careful not to cut the actual cable.
– Strip the protective rubber about 1/2″ back exposing the metal structure of the cable housing.
– Measure/mark the length of cable needed for when your foot is off the gas pedal & when it’s all the way down. Do the same on the extension end, this time using the actual throttle assembly. If you need to expose more cable on either side, cut off more of the housing.
– Once you get the lengths right, using a 1/16″ ferrule (you may need to enlarge the hole to allow both cables to fit), crimp the 2 cables together.
– Using some 5/16″ ID fuel hose I had sitting around, that acts as a protective covering for the exposed cable/ferrule. Make sure the crimped ferrule can slide through it easy enough.
– Use some heat shrink tubing on the ends of the joint to keep moisture & dirt out.
– Then some clamps to hold the hose onto the metal housing

Alternator Bracket

The 20V has a huge alternator bracket with an idler pulley so that the belt doesn’t interfere with the chassis. You can reuse the 16V NA bracket on the 20V block. However, on the blacktop you will need to cut away some material to clear the hydraulic timing belt tensioner.



Oil Pressure Sender

Use the 16V oil pressure sensor, as the Trueno/Levins just have an idiot light instead of a gauge.

Clutch/Flywheel Info

If you are replacing the clutch or flywheel make sure to get one for a C series transmission. The MR2 SC clutch/flywheel will NOT fit. The shaft on the C series trannies are smaller than the E series.

Mounting (ECU, MAP, Ignitor/Coil, Coolant Overflow Bottle)

Fab mounts for the ECU in the new driver’s side location.

For the blacktop, mount the MAP sensor at a convenient location near the #1 intake side. I used an existing welded nut on the chassis.

Same goes with the ignitor & coil, but this time near #4. I chose a place on the strut tower. 2 bolts fit perfectly in existing holes. A third hole was drilled and tapped.

Since the filler neck was on the opposite side of the engine bay, I had to use a different location for the overflow bottle. I decided to use a different bottle altogether since mine was weathered pretty bad. Just using a cheapo from Autozone at the moment.

Vaccuum Lines

The 20V has 2 brake booster lines coming off the TBs. Luckily both are on the #1 side of the engine, making it easy to route the hose to the MR2’s single booster line. I used the one that comes of the #4 TB, since the #1’s fitting can be easily removed and a bolt inserted to block it off.

You can also block of a line that was used for the power steering system in the Levin/Trueno. Near the fuel rail by #4 cylinder there should be 3 hoses, each of distinct sizes. It’s the middle sized hose that can be capped.

Crank Pulley

If you have the Silvertop, make sure to use the 16V crank pulley and timing marker. This helps with adjusting the ignition timing. On the blacktop, you can’t use the 16V timing marker since it uses a different tensioner. However, make sure to paint marks along the crank pulley, on all edges. The belt gets in the way of the inside mark making it hard to see.

Decklid Latch

The intake box on the Blacktop interferes with the engine latch. So grind away at the latch until there’s room. I had to bend one side of the latch slightly, as well as remove the bottom bolt hole to make room for the coupling to the air filter.

Axles & Tranny Stiffener

The Levins and Truenos have equal length drive shafts. Unfortunately these shafts are an inch or 2 too long to use in the MR2. The MR2 axles fit fine of course, so it may be possible to Frankenstein something together. The cup of the 20V extension shaft on the passenger side is too large for the MR2’s tulip joints. You may be able to remove the tulip joint from the 20V axle and refit it to the MR2’s axle. I’m not sure. This is something I may try later, as I have a spare driver’s side MR2 axle.

Also, if you use the MR2 axles, the 20V tranny stiffener will not fit. You can either grind away some of the material to make the stiffener fit, or just run without it. To make it fit I believe you need to chop 1 corner off, using one less bolt holding it in place.

This documentation in no way replaces the Toyota MR2 Repair Manuals. The purpose of this content is only to provide supplementary information to fellow MR2 enthusiasts. Midship Runabout and its contributing authors will not be held responsible for any injury or damages that may occur as the result of practicing any of the methods or procedures described within this website. Article and photo submissions are property of the contributing author.

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