Type 1 VW versus KL-ZE V6 versus EJ20T (WRX)

Here is a comparison between my existing 1915cc Type 1 VW motor, my future 2.5L KL-ZE V6 Mazda Motor and the other likely VW engine option which was a Subaru WRX EJ20T.

Engine VW Mazda Subaru
Model Type 1 KL-ZE (jap version) EJ20T (jap version)
Engine Type Modified Type 1 Vw motor. Flat 4 cylinder, pushrod single cam, alloy heads and case, steel cylinders. 044 Big Valve heads, high ratio rockers, balanced, other goodies Standard Mazda engine. Six cylinders, V6, belt and gear driven DOHC per bank, all alloy, cross-flow cylinder heads with cast-iron cylinder liners. Variable Resonance Intake System. Standard Subaru WRX engine, flat four boxer, DOHC per bank, alloy head and block, turbo charged. 
Size 1915 cc 2497 cc 1994 cc
Cylinders / Config Flat 4 Boxer  60 degree V6 Flat 4 Boxer
Bore 94mm 84.5mm 92.0 mm
Stroke 69mm 74.2mm 75.0 mm
Valves per cylinder 2 4 4
Induction Twin IDF Weber carbs. Multipoint EFI  Turbo EFI
Power (see graph below) 100HP 200HP @ 6500rpm 217HP@ 6400rpm
Torque (see graph below) 150Nm 224Nm @ 4800-5500rpm 269Nm @ 4000rpm
Compression 8.5:1 10:1 8.5:1
Firing Order 1-4-3-2 1-2-3-4-5-6 -
Redline 6000rpm 7800-7900rpm 7500rpm
Rev Limited No Yes Yes
Alternator 55 Amps 90 Amps 75 Amps
Heating No Yes Yes
Air-conditioning No Yes Optional
Climate Control No Yes Possibly
Cooling Air Cooled Water Cooled Water Cooled
Expected Life (between rebuilds) 100,000+kms 250,000+kms Rumoured less than 
 150,000kms if driven hard
Sump to crank centerline depth ~190 mm (200 mm type 4) ~210 mm ~280!!! mm
Engine Weight
(found wide ranges so far, will try to confirm)
98-125 kg type 1
125-140 kg type 4
* Both unconfirmed, maybe bare engines
176kg complete motor with all accessories and exhaust back to the cat. Confirmed with load cell. 147 kg for EJ20T

130kg for non turbo EJ20

*from SAE paper

Expected 0-100kph 9.1 seconds 5.8 seconds

(6.3s tested so far)

4.9 seconds
Expected 0-400m 16.7s @ 130.7kph 14.6s @ 153kph

(14.8s@152kph so far)

13.7s @ 162kph
Note - 0-100kph and 1/4 times calculated using my excel calculator found here Excel Dyno Calc , with an estimated vehicle weight with driver (and stereo and raditator, etc) of 1050kg. I will weigh it one day.
Advantages Smallest & lightest engine. Also simple, not much to go wrong. No conversion work needed. Will fill the engine bay the best. Excellent low down torque for offroading. Sweet sound. Easy to mod turbo and get more power. 
Disadvantages Lacks power, refinement,  and longevity.  More cylinders so higher rego cost. Hard to get much more power from unless you go turbo / supercharged. Check out 800HP twin turbo version. Very low sump and turbo bad for offroading. Conversion been done before.   
Price 2nd Hand $2500+ $2500 (half cut)
-$150 (sold gear stick, steering wheel)
-$450 (sold gearbox)....
Cost to install $0 +$165 (fuel pump)
+ $? (adaptors)....
(will be updated thru transplant)
$2500+  see Jan of the V6 diary ?


***NOTE - These charts and estimated vehicle accelerations have been updated, as I do not believe the original dyno chart I had for the KLZE was accurate. I think the car that was tested must have had a few additional modifications. I also updated the Subaru charts to show the jap spec engine, as I figure that's what most people would actually put in anyway. The Jap EJ20T has slightly higher compression and probably runs different boost.

The VW engine dyno chart came from Hot VW's magazine for a 1915cc VW motor with Street Eliminator heads and 44IDF webers.

The Subaru dyno chart came from here

The Mazda dyno chart basically came from here (- site removed). But that chart is for the lower compression, smaller port, smaller cam KL03/KLDE Australian spec motor (also US spec). I then had to modify the higher end of the power curve to get the quoted 22.8kgf.m of torque @ 4800-5500 (depends on specific model), and 200HP @ 6500rpm for the KLZE version of the engine. So the KLZE probably has more torque in the low end and mid range than what is shown in the charts below, and various peoples dyno testing has shown this.

Power Graph

Below is a graph I have made of the different engines HP curves. It is the best average values I could find from many dyno charts I came across. This is also the second revision, as the first graph I had here for the V6 seemed to have way too much torque in the mid range. I will probably dyno mine one day. From this graph the KL-ZE and the EJ20T look similar, with the EJ20T having a nice surge over 2,500rpm when the turbo kicks in. The V6 stays very linear with it's power delivery, and you can feel that when you drive it.

Torque Graph

Below is the torque graphs for the engines. This graph tells a much different story. Here you can see the broad torque advantage of the Mazda engine. Down low (like 1000-1500) where I need torque for offroading and normal traffic driving (up to 2,500rpm), the Mazda is in a league of it's own. I have not been able to find accurate torque data below 2,000rpm, but the information I have suggests the V6 produces 125ft.lb of torque at 1,000rpm. That is more than the VW motor produces at peak torque!