Building an LS/VTEC is not for the feint
of heart or shallow of wallet, but it is worth all the time and money
that it will take. In this article I will assume that you have read
our
recommended parts list, you have an understanding of engine
building, you own a
Helm's (or equivalent) manual, and you have the parts you need for
the minimum (in my opinion) build. An engine stand is a nice tool to
have, it is not necessary but it is very helpful. You can get them at
any major parts store; I got mine from AutoZone for $65.
Our LSVTEC parts list gives several options, here is the list (beyond
block and head) that I would call a minimum:
- Pistons from any B16 because LS
pistons do not have large enough valve reliefs for VTEC intake
valves. Forged pistons would be better, but if you can afford them
B16 pistons will work well.
- New piston rings. Honda rings work
well, or you can use your preferred aftermarket.
- Cam gears (brand is up to you, some
folks have had trouble with AEM gears slipping, after replacing the
bolts, I have had no trouble with my AEM gears).
- A B series DOHC VTEC distributor. An
LS one will work with some serious modifications, but this is not a
good idea.
- An ECU that matches the OBD of your
engine and that is setup to run a DOHC VTEC engine. I run a P72, but
a P30, P61 or a chipped P28 would work fine for an OBD1 car. Also,
if you are using a GSR head, and the stock intake manifold, you are
going to want a P72 from the GSR inorder to control the IAB
butterflies.
- Water and oil pumps from a GSR or
ITR. I don't consider using the LS water pump an option as it is
likely to cavitate at high RPM. This means you have to run the GSR
timing belt.
- ARP rod bolts. If you are using LS
rods this is not a must, but it is a damn good idea. The stock LS
bolts were not designed to handle the forces of 8000 RPM. $55 is not
much to pay for peace of mind.
- ARP head studs. They hold better
than stock and you don't run the risk of destroying the threads in
the block every time you pull the head. You want the studs for the
B18C1.
The Block
First, the modifications that you will need to perform on the bottom
end. You won't actually change anything in the bottom end, just the
normal steps that you would take if you were rebuilding the engine.
Once the bottom end is disassembled you should take it to a machinist
to have the cylinder walls honed, make sure that you keep the piston
to wall clearance within spec for the pistons that you are using. It's
a good idea to bring your pistons and rngs to the machine shop with
you so that they can perfectly spec them to match. Have your crank
polished, and have the rotating assembly balanced. When you are
reassembling the bottom end make sure to check all the bearing
clearances with plastigauge. I am not including any pictures of the
bottom end rebuild because they can all be found in your Helms manual.
The Head
There are several modifications in this step; first you will need to
have a machinist open the holes on the intake side of the engine to
accept dowel pins. Pictured here:
One dowel pin has my finger and a red arrow pointing to it, the other
is on the opposite side of the picture with just a red arrow. This is
where they need to be, when you first get the head the pins will be on
the exhaust side of the head.
Next you will have to tap the VTEC oil passage and plug it using a set
screw. This passage is in the picture above, it is below my hand and
has a red arrow pointing at it. If you bought a kit for your oil line
it most likely came with a set screw to plug this passage. 3/8" NPT to
either a -3 or -4an line, depending on your line/kit. It HAS to go
into the head far enough so that it does not affect the way you head
sits on the gasket! Make sure to apply a little thread lock to this
set screw.
Next you need to decide where you want to run your oil line. There are
two spots where the line can attach to the head. Shown here:
My finger and the red arrow are pointing at the first; this is where
the LSVTEC kit from
InlineFour
will run the oil line. The other spot is at the bottom of the picture
with a blue set screw in it. Either place will work, it depends on
what fittings and line you can acquire. Make sure to use Teflon tape
on all of these connections except the two connections to the external
oil line, as they will be self sealing.
Make sure to clay your engine for proper clearances if you are running
aftermarket cams and/or aftermarket pistons. When you are assembling
the engine, make sure to use generous amounts of assembly lube on any
metal to metal contact area except your piston rings. Use regular,
non-synthetic, engine oil on them. This will protect your engine for
the first few seconds that it runs before your oil starts flowing.
If you bought a VTEC conversion Sandwhich adapter, you can skip the
next step.
Now you are ready to install the oil T on the block. Next to the oil
filter will be your oil pressure sending unit. Remove the sending unit
from the block. This is where you will be installing the oil T. Shown
here:
Install the T before you install the oil filter.
First, apply some Teflon tape to the adapter that will be threading
into the block, make sure to apply the tape to the side that will
thread into the block and the side that will thread into the T. Start
the adapter threading into the T, then thread the T into the block.
Make sure it is snug, but be careful not to over tighten.
Next, apply some Teflon tape to the oil pressure sending unit. Then
thread the sending unit into the T. It does not matter which spot on
the T that you use. I chose up because it made routing the oil line
more simple. Apply some Teflon tape to the end of the fitting that
will thread into the oil T and install it. Again, make sure everything
is snug, but be careful not to over tighten.
Now install the oil line. If you are using the InlineFour or a smiliar
kit, your assembled engine should look something like this:
Now install the engine and tranny. Procedure on this is out of the
scope of this article, however, wiring it up is not.
Finishing Touches
You will have to run 2, 3, or 4 wires through the firewall to the ECU.
Two to the VTEC solenoid, one to the knock sensor (if your ECU
requires one), and one to the IAB (if you are using the gsr head with
the stock intake manifold for the butterflies). Where you run these
wires to on the ECU depends on your OBD version and which ECU you are
using. You can ground the VTEC switch to the engine or any good ground
source, so there is no reason to run that wire through the firewall.
As long as you have everything hooked up properly your engine should
start.
Put her on the Road
Onto the break in, there are man theories on how to properly break in
an engine. Here is the method I used:
Make sure the floor beneath your engine is clean, or lay some
newspaper down. On the first start up, turn the idle up to about 2000
RPM and let the engine come up to operating temp. Make sure that you
are flowing water and that your fan(s) kick in when they should. While
your engine is warming up check for any leaks; this is where the clean
floor comes in handy. If you don't have any leaks take you car out and
do a couple of 1st gear pulls at 1/2 to 3/4 throttle stopping at 4500
or 5000 RPM. This loads the rings to help them seat to the cylinder
walls. Then do a couple 2nd gear pulls the same way, then some 3rd
gear pulls. Now change your oil. Drain the oil into a clean open pan.
Check the oil for metal. There will be some, but make sure you don't
have a lot of metal floating in the oil. If you have a lot of metal in
the oil you should disassemble the bottom end and check all your
bearings for excessive wear. You probably have a rod or main bearing
that does not have enough clearance. If everything is clear then drive
your car for about 1000 miles. Try not to exceed 4500 RPM for the
first 150 to 200 miles, and then increase the revs that you use as
mileage increases. I would not drive it really hard until you are
finished breaking it in, but you can use the full rev range after
about 600 miles (assuming that you haven't developed any problems).
Change the oil again at 1000 miles. It is now safe to run synthetic
oil (in fact I recommend it). I used this break in method on my car
and the engine is running very well. Not burning any oil and it is not
smoking at all.
I hope you found this guide helpful. The normal disclaimer applies:
Neither Hondaswap.com (including its owner, and staff) nor myself are
responsible for any damage you do to your car. I have written this
guide to the best of my ability and these steps are the same I used
when building my engine. If you are unsure about any step or feel that
this guide could be improved in any way please contact me at eric@hondaswap.com.
Thanks for reading and good luck.
