How To Assemble your LS VTEC Build

How To Assemble your LS VTEC Build

2
SHARE

Like any engine project, the key to a successful and reliable LS VTEC build is planning and knowledge. When you take the time to properly research just what makes a reliable LS VTEC build the chances of your success are greatly increased. Your project Honda will run longer, you’ll have less problems and your Frankenstein engine will have a greater chance of serving you for many years to come.

However there’s a great deal of misinformation out there on the Internet about the LS VTEC build. Just check out some of the common LS VTEC myths that you would do well to avoid in your engine. The key is having the right amount of information, because despite what many think there’s no one method to assembling your LS VTEC engine. There are so many combinations out there, from a CR VTEC from a B20 or any number of B18 LS engines, which is why the right amount of research is paramount.

Today we’ll be going over the steps and checklist to assembling your LS VTEC build. Keep in mind that you should have this as a guideline before you begin. We will begin with the basic checklist of parts you’ll need for any good LS VTEC setup.

Parts required for your LS VTEC Build

Head Gasket – There are a few different options you can go with here. From a new OEM Honda LS non VTEC gasket from a 1990-2001 Acura Integra, or an aftermarket unit. If you are retaining the stock bore, it’s 81mm for an LS and 84mm for a CR-V or B20 short block.

How To Assemble your LS VTEC Engine 7

ARP Head studs – One of the best tried and true head stud kits on the market, you will want the part number 208-4306. With the ability to hold things together even under boost, these head studs are great for your LS VTEC engine.

You will need to swap out the middle two bolts for a LS VTEC build. This is highly recommended because otherwise the LS bolts will be too long. You can choose to go with a GSR head stud kit from ARP as well.

These part numbers are ARP part number atp8.000-1LUB to ATP6.000-1LUBA which is two of the 11mm hex bolts from ARP. Two of that part number will transform your LS ARP head stud kit into the right one for a proper LS VTEC build.

ARP Rod Bolts – Essential for any reliable LS VTEC engine. Because the rod bolts in your non VTEC engine from the factory will stretch at high RPM, this is a must have mod for your LS VTEC build. The part number for your ARP rod bolts is 208-6001.

Timing Belt – There’s a few choices when it comes to your LS VTEC timing belt. If you are running a GSR water pump, you’ll need the matching belt. If you want to use a LS water pump, it’s the non VTEC version that you will need. The part numbers for these belts are 14400-P72-004 or 14400-P72-014 for the VTEC version. The non VTEC LS with the B18B is part number 14400-P7J-004 or 14400-PR4-A01.

How To Assemble your LS VTEC EngineThis is the only difference you will have to note here, as the cam gears should match. When assembling your LS VTEC build make sure that your mechanical timing is on point.

Water Pump It’s also a good idea to install a new P72 water pump at the same time. When shopping for your LS VTEC water pump make sure it matches up to your timing belt selection.

The difference between VTEC and non VTEC water pumps is 3 teeth. To avoid a mistake, take the time to properly match the water pump and replace your gasket as well. This ensures that the front of your LS VTEC build is ready to go from the jump. While you are at it, it might be a good idea to refresh the gaskets and seals here, like your cam seals. As a general rule of thumb assembling your LS VTEC engine with new seals to prevent leaks and any issues.

LSvsGSR

New bearings – There are quite a few options as far as bearings go. ACL and Hastings are two choices as far as aftermarket manufacturers go. Make sure that the bearings are properly set and installed with a high quality engine torque wrench and plastigage.

New Oil Pump – A common part that’s often overlooked, a new oil pump can go a long way towards your reliability. Use any 1996 and up Acura Integra oil pump or a B16 pump. If price is no object go with a Type R oil pump for reliable oil pressure.

Optional things to include with your LS VTEC build

  • Shotpeen the rods
  • New valve stems
  • Hone cylinders
  • New piston rings
  • Adjustable cam gears
  • Higher compression pistons – OEM pistons P30(SIR2 B16)/P73(ITR)
  • Upgraded injectors – 330 cc is recommended
  • Chipped OBDI Honda ECU

Before you begin building your hybrid engine there’s a few things you’ll need. These are fluids and the simple basics to engine assembly. Assembly lube and RTV along with non-synthetic engine oil and coolant are just some of the required fluids.

Install your LS VTEC engine kit

If you haven’t done so already, install your hybrid engine kit. This will include the proper LS VTEC cylinder head plugs, and the oil fittings to retrofit your VTEC solenoid. These parts can vary from a sandwich adapter to your oil filter, or an 8th inch NPT fitting for your oil feed.

how-to-build-a-reliable-ls-vtec-1

 

You will need to tap your VTEC cylinder head to block off the oil passages that exist there. Because there’s no provisions in your non VTEC shortblock, you’ve got to install these plugs to block off the oil.

This helps you maintain oil pressure in your LS VTEC build. The set screw in your cylinder head must be removed and tapped for an 8th inch NPT fitting.

Don’t forget to teflon tape the plug so that it promotes a positive seal in your VTEC cylinder head.

The last step of your LS VTEC kit should include the cylinder head bosses otherwise known as dowel pins that insert into the head stud openings. You will need a stepped down or tapered fitting to properly fit your VTEC cylinder head onto your LS block. When in doubt use the two corner exhaust side head bolt holes for your aftermarket dowel pins.

How To Assemble your LS VTEC Engine 8

 

Assemble your VTEC Cylinder Head

There’s quite a few VTEC heads to choose from when you want to plan your LS VTEC build. While many enthusiasts will argue the benefits of B16 vs GSR heads, the fact is either is a great choice. VTEC heads is one area where you should not opt for a Type R cylnder head, because the cost is so prohibitive. Save that money instead and invest in your B16 or B18C1 cylinder head for greater results.

The PR3 cylinder head cast is an excellent choice, and there’s several engines that spring from this cast. The Type R, B16 and 1992-1993 Acura Integra GSR heads are built from this cast. The more common casting is the P72 cylinder head, which is the GSR version from the 1994-2001 Acura Integras.

Not sure which Honda engine you have? or don’t know how to identify your B16? With just a little bit of help and guidance you can find out the information on what cylinder head you are using.

Should I get a B16 Head or a GSR Head?

One of the oldest questions and often argued points among Honda gear heads. While there are differences between the two in stock form, there’s no real bad choice here. One of the biggest differences of course is the intake manifold. The B16 intake bolt pattern is the same layout as a Type R, which are easier choices for aftermarket intake manifolds.

GSR cylinder heads also feature quench pads, which help fight off pre-detonation and promotes more efficient combustion. If you are going with high compression pistons and a GSR head, it might be a good idea to have your engine tolerances checked. This can help avoid disaster especially if you’ve bought the cylinder head used.

 

Install your ARP head studs

How To Assemble your LS VTEC Engine 6

Before you install ARP head studs make sure to chase the threads in your shortblock and clean it properly. One of the biggest mistakes in any LS VTEC build is people just screwing the ARP head studs into the block without the right amount of prep.

Clear the holes of any debris using brake cleaner and blowing out the holes with an air compressor. Chase the threads using one ARP head stud and clean thoroughly. Use the supplied ARP moly lube generously to the threads when you are ready to start installing your head studs.

Screw in the ARP head studs all the way down and back off a 1/4 turn so that you give the bolts enough stretch room. Never torque the head studs into the block and make sure there’s the recommended gap between the bottom of the engine and your ARP head stud.

Install your VTEC head

If you are using stock or factory camshafts this part is relatively straightforward. If you are sticking to the stock compression in a LS or your CRV shortblock, no further steps are needed. Assembly lube is required here and refer to the chart below for the torque settings.

How To Assemble your LS VTEC Engine 4If you are upgrading your cams, it’s a good idea to upgrade your valvetrain as well. This keeps you from making a common mistake that many LS VTEC builders make.

Type R dual valve springs can be had for cheap, or aftermarket units are also a great choice. The last thing you want to do is drop a valve at high RPM.

When you’ve set your VTEC head in place, install your camshafts and apply a generous amount of assembly lube. Apply to the VTEC lobes, journals and the cams themselves. Don’t forget to identify the intake cam as the one with the slot in it for your distributor.

The cam caps should already be identified and laid in place. If you are buying a used VTEC head, make sure to ask for the right cam caps and the proper orientation. Using a different set of cam caps is asking for trouble. Because each cylinder head is different, picking up a used set of cam caps may lead to engine failure or premature damage. In many cases a line hone is required which makes using different cam caps completely cost inefficient. The caps are labeled I or E for intake and exhaust, and should be numbered 1 for cylinder 1 to 5 from the timing side of the engine to the distributor side, respectively.

Wiring up VTEC and installing the solenoid

Install your VTEC solenoid and if you haven’t already check our guide on wiring up VTEC. Make sure that all of your temperature sensors are properly teflon taped and installed. The dummy sensor is a one pin connector, where as the temp sensor is a two pin unit that your Honda ECU uses.

How To Assemble your LS VTEC Engine 9

 

 

Wiring up the VTEC pressure switch and the solenoid is simple to do. Run the wires to your ECU and either wire them in manually or de-pin your ECU connector and install these new wires.

If your VTEC is not engaging check our guide on troubleshooting your VTEC. There are many reasons why your VTEC is not working, check our guide above to see the Top Ten reasons why your VTEC isn’t engaging.

Check the torque specifications at the bottom of our LS VTEC build page to see what you should be torquing the sensors to.

Installing your distributor

To avoid having problems it’s a good idea to run a VTEC or GSR distributor. If you are intent on using a non VTEC distributor, the front leg of the LS distributor must be cut off. Typically however it’s not a good idea to use a LS distributor for your LS VTEC build. Because this leg will hit the VTEC solenoid, and only one bolt will truly line up.

If you are switching from OBDI to OBDII or vice versa, check the guide on converting your distributor accordingly.

 

 

 

Important torque settings for your LS VTEC build

  • Oil pan to block nuts/bolts – 8.7 ft/lbs
  • Oil drain plug – 33 ft/lbs
  • Oil pickup tube to block/oil pump – 8 ft/lbs
  • Windage tray bolts – 8 ft/lbs
  • Flywheel to block bolts – 76 ft/lbs
  • Fuel filter bolt – 25 ft/lbs
  • Tensioner pulley bolt – 40 ft/lbs
  • Crank pulley bolt – 130 ft/lbs
  • Cam gear bolts – 41 ft/lbs
  • Exhaust manifold/Header to cylinder head nuts/bolts – 27 ft/lbs
  • Intake manifold to Cylinder head nuts/bolts – 18 ft/lbs
  • Rocker arm locking nuts – 14 ft/lbs
  • Camshaft holder plate bolts (12mm) – 20 ft/lbs
  • Cam caps (10mm) – 7.2 ft/lbs
  • Pressure plate to flywheel bolts – 19 ft/lbs
  • Main bearing caps – 56 ft/lbs
  • Oil pump to block (12mm) – 17 ft/lbs
  • Oil pump to block (10mm) – 8 ft/lbs
  • Water pump to block bolts – 8.7 ft/lbs
  • Thermostat to block bolts – 8.7 ft/lbs

Once you have your LS VTEC build assembled, make sure to use the proper break in techniques to ensure a long life and proper ring seating. Have any questions about this guide on the ultimate LS VTEC build? Leave them for us below and let us know!

2 COMMENTS

  1. I have a GS/VTEC Automatic (JDM SIR-G transmission) with ITR internals, 81.25 ITR piston, JDM CTR camshaft, Milled, port polish, 3 angle. All fuel system component been upgraded even the injectors to RC310cc. I’m running a JDM P30 Automatic ECU (OBD1) chipped on Neptune jumped from OBD2 to OBD1.

    My question is what will happen when I put the OBD2 P75 Automatic ECU. Need to know what are my options are for SMOG. In my state all they do is plug up the OBD port and read the ECU.

    • Hi Musa, BAR legal Honda engine swaps are definitely pretty easy to do, and it really depends on your ref. I have seen some refs turn down a BAR tag in a LS/VTEC setup such as yours just because of the B18A, and the VTEC ECU not matching. My recommendation is to try looking for a friendly ref in your area that may be more lenient than others. Take your P75 ECU in and speak to the ref about what might be wrong with your swap if he turns you down.

      Sounds like a great project, and you shouldn’t have any issues passing smog, even with your cams. thanks for commenting.

LEAVE A REPLY