500hp+ from a supercharged Honda? Sure. Here’s two.

imw By Derek Robinson – Innovative MotorWorks

April 6, 2016

Over the last couple years, I’ve had the pleasure of working with Jose Mercado of “MercRacing,” a manufacturer of a really freakin’ cool supercharger system for K-Series engines.

This past weekend, I had the opportunity to tune two really awesome supercharged 8th Gen Civic Si’s, both sporting MercRacing setups.



The first was a car that I built an engine for a few years ago, with a Whipple 2.3 liter blower sitting atop the MercRacing manifold, and a custom Garrett 700hp water-to-air intercooler setup.


Benson-sleeved K20Z3

Manley Turbo Tuff rods
CP pistons, 10:1, 88mm bore
Supertech valvetrain
Stock cams
Go Power header, 3″ exhaust
MercRacing Whipple 2.3 Supercharger Kit
Custom MercRacing Garrett water-to-air intercooler setup (core mounted above transmission)

473hp on 93 octane
527hp on E78
19ish psi


IAT’s hovered right around 99-100degF the whole time. No ice was added to the system, the only cooling to the water system was via the front heat exchanger and the fan blowing into it.


The second car was a stock-block 8th Gen Civic Si using the MercRacing TVS 1900 kit, and a front-mounted air-to-air intercooler, like every turbo car uses.


Stock K20Z3 block (11:1)

ARP head studs
Supertech valvetrain
Stock cams
Race header
3″ exhaust
MercRacing manifold
Magnuson TVS 1900 blower
Treadstone intercooler, 2.5″ charge piping

450hp on 93 octane
503hp on E67 (we only had 70% at the pump currently, so switching fuel left us with a lower mixture)



IAT’s on this setup started around 80degF and ended around 104-106degF at the end of a 7 second ramp. On the street, IAT’s didn’t go over 100.

As you can see, the setups both make GREAT torque, literally everywhere. I limit the amount of torque the stock K20 setup makes on the low cam in an attempt to keep the stock rods happy.

I took the liberty of comparing the TVS 1900 against a Rotrex C38-91 on a stock JDM K20A at the same boost level, with 85% ethanol:


As you can see, the Rotrex gets its butt kicked pretty hard everywhere compared to the TVS. Driving these setups is like driving a Civic with a big-block in them; ample torque anywhere you plant the throttle, and simple throttle modulation goes a long way in controlling power delivery to the tire, unlike a lot of big power turbo cars.

I’ll see if I can grab some more photos of the setups; was a long weekend here; the red car drove from North Carolina Wednesday night, and broke fourth gear pulling into town. I ended up renting him some lift space and he had his wife next day air ship him his spare transmission parts, and was ready to hit the dyno Friday afternoon!

As always, if anyone has any questions, as away. I’m an open book.


Derek Robinson

Innovative MotorWorks

Carlisle, PA