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Engine Package : Swapping Parts For Power
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Engine Building: Swapping Parts To Get A Better Engine Package


A. Introduction: What Do We Start With In A B18 Engine?

B. Swapping Out Parts For More Displacement


A. Introduction: What Do We Start With In A B18 Engine?

Integras have low rod ratios (i.e. rod ratio = connecting rod length divided by stroke) and therefore, our engines :

1a) have Short Piston Dwell Time at TDC
1b) have High Piston Speeds Away from TDC
2. prefer Long Duration, Big Overlap Cams
3. need Static Compression Ratio Increases to compensate for big overlap cams
4. prefer Small Port Volumes but these still must be bigger than a B16A's port volume
5. cannot rev as high as the B16A due to a lower rod ratio which increases cylinder wall piston sideloading againt the cylinder wall and as a result, has more vibrations at higher rpms.

This is the engine package characteristics of a B18 engine from which we start with. You can max out on the B18 engine with extreme mods but if you keep the low rod ratio and 1.8L displacement, you can only go so far with this typical high performance N/A engine package with: small port volumes, big overlap cams, big compression, and big header/exhaust. Most people that know how to build 1.8L B18C's and tune them usually max. out at around 215-225 peak whp for a reliable daily-driver. This thread will cover what we can do to change the odds in our favor to get more than this by swapping out parts to get : a) more displacement, b) a better rod ratio, c) a better engine layout (called oversquare layout).


Skip this section and go to Page 2 if you already understand what rod ratio is and how it affects engine cylinder filling, cam choice, and headporting port sizes.

The "features" of a 1.8L B18 N/A engine briefly are:

1. Piston Geometry: Honda B18 series engines have a low rod length to stroke ratio or "rod ratio". For the Honda Integras, the rod ratio is in the low range at 1.54-1.58. The rod ratio determines the way the piston behaves as it travels up and down the cylinder. This behaviour is called "piston geometry". The consequence of the B18's piston geometry are :

1.a) they spend a shorter time at Top Dead Center (TDC) [which is at the very top of the piston travel] compared to the B16A. This is called a Short Piston Dwell Time.

With short piston dwell time, there is less force compressing the air:fuel mix on the compression stroke and the piston quickly changes direction downward as the mix is being ignited. The air fuel mix, with less compression force and rapid change in piston direction downward, does not combust as completely.

Secondly, on the upward exhaust stroke, the piston quickly changes from pushing the burnt exhaust gases out of the combustion chamber to sucking in fresh air:fuel at the start of the intake stroke.

We have fast transitions from compression to power strokes and exhaust to intake strokes. The piston changes direction or flip flops at TDC quickly at each engine cycle or stroke (intake, compression, power, exhaust strokes).

1. b) the piston drops down very fast away from TDC during the intake stroke and power stroke. This is called high Piston Speed Away From TDC.

On the intake stroke, high piston speeds away from TDC generates high flow velocities through the intake port at low-midrange rpm because the piston has a higher sucking force to draw in more intake air:fuel mix into the combustion chamber at low-midrange rpms.

On the power stroke, high piston speeds away from TDC unfortunately means the piston can run away from the spark flame front travel causing incomplete burning of the air fuel mix.

High piston speed away from TDC also reduces cylinder pressures too rapidly, especially at high rpms. This lowered cylinder pressure reduces the force downward on top of the piston making less power.

1 c) More importantly, with a low rod ratio, the B18's cannot rev as high compared to the B16A, due to a larger angle created between the connecting rod and the crankshaft (called the "rod angle")as the piston travels. Higher rod angles increase wear damage and vibration due to increased piston sideloading on the cylinder walls. Rev too high and you can push a piston through a cylinder wall into the coolant jacket.

2. Camshaft Choice: With the piston geometry described in 1. , B18 engines like Long Duration, Big Overlap Cams because we need more scavenging and time to fill the chamber, especially at high rpms .

eg. of high overlap cams :

- for the B18A/B Crower 62403 or 62404.

- for B18C Toda Spec B, Jun Type 3, Skunk2 Stage 2, Crower 63403, Zex 57300.

The exception to this rule is when we add nitrous, a turbocharger, or a supercharger. Intermediate overlap, short duration cams are chosen to prevent the boost from shooting into the exhaust manifold with a long cam overlap.

eg. intermediate overlap short duration cams for forced induction:

for B18A/B - Crower 62402/62403, Crane 101-0014 turbo cams

for B18C - Toda Spec A, Jun Type 2, Crower 63402/63402A, Zex/Compcams 57100 or 57200, Crane roller 253-0510 cams with roller rockers.

However, with more intake cam duration there is a greater chance of cylinder pressure being lost out of the opening intake valve. We lose dynamic compression . Along with High Piston Speeds Away From TDC, big overlap cams will reduce cylinder pressures and prevent efficient burning or combustion of the air fuel mix.

3. Port Sizing: the B18's like small cross-sectional port area and longer port length on the cylinder head intake ports to maintain high flow velocity and flow quality. However, the B18's preferred port size is still bigger than the B16A intake ports.

So this is where we start from with our B18 engines. Are we stuck with 1.8L displacement, big overlap cams, lower redline, and a low rod ratios? Of course not! This is why we swap parts to change the engine package's piston geometry, displacement, and it's breathing ability. The next section deals with doing this.

B. Swapping Out Parts For More Displacement

The most common attempt people try to do in order to get more power reliably is to get more displacement.

Increasing your B18's displacement to 1.9-2.1 L guarantees a noticeable gain in torque especially in the lower to midrange rpms. Most of today's 10 sec 1/4 mile et , all motor B18's have at least 2.0L.

There are 3 ways to get more displacement:

1. Increasing the Stroke
2a. Increasing the Bore
2b. Mixing & Matching Increased Both Bore and Stroke
3. Swapping for a B20b/z shortblock or a complete H22A VTEC swap.


1. Increasing the Stroke

I don't recommend this method of increasing displacement. There. I got it out of the way first so you don't waste your time and can move on to method 2.

I guess for most of you though, there has to be a reason why and so I'll go into a little more detail:

There are four ways to increase the stroke.:

1 a) Use a brand new custom-made billet crank. (This usually is wicked expensive.): AEBS, Eagle, etc.

1 b) Use a crank from a different Honda engine. (Some people more recently have used an 1989-1991 Prelude B20A or B21A crank with 95mm stroke and custom 134 mm Crower rods.)

1c) Modify stock crankshaft by offset grinding .

This is done by making the journal smaller, thus the center line of the journal is moved outwards, so the stroke increases. You are usually limited by the materials you can safely take off. Another tricky part is, where are you going to find the bearings that'll fit? You can always get custom rods with the length and big ends to your spec, but (custom rod) bearing size needs to be considered.

1d) A good crank shop will be able to weld up your stock crankshaft and then, re-finish it (with stock crank journal size). The V8 guys have done this before and it will work fine.

Crower, RPS, Peter Yem Racing (PYR) , Top Fuel, Jun, and Spoon make stroker kits for the B18's. The displacement ranges from 1949 cc to 2012 cc using a stock Honda piston overbore of 81.25 mm. Some kits provide overbore pistons for 81.5mm to 82mm and the displacement starts at 1961 to 1986 cc.


There are several problems with stroking the motor however:

1 e) You end up with an even lower rod ratio than stock!!

Crower uses a 92-95mm stroke for the non-custom reworked factory cranks. PYR uses a 94.5mm stroke. Jun, Top Fuel, and Spoon uses a 94.0 mm stroke.

(Remember that the stock strokes and rod ratios respectively are for the B18A/B and B20B/Z 89mm/1.54 and for the B18C 87.2 mm/1.58. A good rod ratio for high revving is considered to be from 1.66 to 1.78 with 1.75 being "ideal").

One of the problems with these longer strokes is that the builders must use a 133mm to 134.5 mm rod length so that the rods and pistons fit inside the deck height of the B18 blocks. Therefore, the rod ratios end up ranging from 1.41 to 1.43 (in other words lousy). You cannot rev these engines past 8,000 rpm without severe vibrations. The risks of excessive wear over time and a piston going through the side of the cylinder wall increases as you move the redline higher, unless you re-sleeve your cylinders with re-inforced iron ductile or stronger cylinder liners (add even more cost to compensate for an unwanted side effect of stroking).

1 f) You must notch (ie. take off material as clearance reliefs) the block and in the B18C blocks, remove the block oil squirters to allow crank main journals clearance. Most shops will include notching and squirter removal in their overall pricing for stroking the motor.

After doing these clearance adjustments for the new crank, there is even less lubrication in an engine that needs even more lubricating with a poorer rod ratio.

Notching is indicated by the red arrows for the rotating crankshaft's clearance:

1 g) The cost is prohibitive for most people and there are more cost effective ways to bump up displacement.

The average cost is more than $2500 US for these kits (the Jun kit is $6000 US!... Yeeha!!) and the down time for your engine is over 2 months.

This is one method I do NOT recommend, as I said before, due to the reduced rod ratio, loss of oiling, extended down time, and cost.

If you were a true engine builder (and rich) then, I guess you could also add deck height by welding on a block riser or deckplate and then use a longer rod that will achieve a better rod ratio. The piston may have to be custom made with the pin location moved up higher into the lower piston ring to allow you to keep the same deck clearance. But now your project costs are beginning to go through the roof!! Stroking and welding on a deckplate with custom rods/pistons aren't cheap.

Added Deck Height By Welding On A Deckplate to Allow For A Longer Rod To Get A Better Rod Ratio:

from Endyn on how to add a deck plate

First the block is etched slightly for cleanliness. The upper portions of the iron cylinder are bored out.

The head plate (which is already profiled on the jacket side) is placed on top of the block. All surfaces to be welded are relieved so the weld will achieve maximum penetration.

The two pieces are then heated to 400 degrees, and the welding begins while temperatures are held as constant as possible.

The welding includes the exterior perimeter, and inside the OE bore size cylinder "holes" in the plate. So the bores of the plate are welded to the Honda parent aluminum cylinder exterior. The block is then placed in the oven to "normalize" the aluminum (both factory and the plate/ weld).

Once this is complete we re-heat treat the block assembly to our specs. This process is an absolute necessity if future "movement" and strength is desired. The process is also very traumatic, and the amount of warpage is considerable, so we use four "master" location points, and remachine the entire block. The main bearing housing is one of the first areas, since we use this to bore on center each cylinder, removing slight amounts of material from both the plate and the original aluminum bores. The block is then gradually warmed to 200 degrees, and the "frozen" composite cylinders are shrunk into place.

Composite doesn't necessarily mean what you may think. In this application it's a multi alloy / ceramic imbedded sleeve that gives the cylinder / piston some adiabatic and low friction qualities. All surfaces are remachined, all bolt holes are remachined and all threaded holes are either sleeved with steel threads or machined to a size we feel would be benificial to block integrity.

The crank bore is finished honed, and the cylinders are diamond honed to spec.

2a. Increasing the Bore

You can increase displacement by increasing the bore of the cylinder.

There are 3 advantages to this method:

i) you open up the area on the cylinder head bowl (combustion chamber roof) around the intake valves (called "deshrouding"). This allows for better breathing.

ii) you do not lower the rod ratio like in the case of stroking and this allows you to have an "oversquare" engine layout. Oversquare engines mean that the bore > stroke. A square layout means bore = stroke (like on the RSX K20 engine). An "undersquare" layout means the bore < stroke. Having and oversquare layout and maintaining your rod ratio allows you to rev higher compared to stroking an engine. Currently our B18 engines in stock form are undersquare (Bore 81mm vs Stroke 87.2-89mm) . The Formula One and FIM World Superbike/FIM Grand Prix bike racing engines were all oversquare engines in 2001.

iii) The cost and down time is much less compared to stroking. There is no welding required. However, if you bore out past 82 mm, you must re-sleeve the cylinders with stronger thicker re-inforcement sleeves because the B-series engine blocks have an open (cylinders are unsupported) deck (stock Honda B18 bore from the factory is 81mm and replacement Honda overbore B18 pistons have a bore of 81.25mm).

Figure 1. A B18 Block showing the siamesed cylinders and open deck layout where the cylinders are unsupported by the block because of a coolant channel which places a gap between the block outer wall and the cylinder wall. Honda did this to fascilitate cooling at high rpms due to the heat generated by low rod ratios in the B18's. Notice that the head bolt holes are not directly beside the cylinders and they go all the way down the height of the open deck block. Therefore, no torque plate is needed to prevent buckling or distortion of the cylinder walls during head bolt/stud torque down during boring/honing to ensure a perfect circle in the cylinder.

If we maintain the stock crank, here are the displacements you can get by increasing your bore:

I. for the B18A/B18B (89 mm Stroke)

Bore (Stock 81 mm) ....Displacement (Stock = 1834 cc)

82 mm..................1880 cc

83 mm..................1926 cc

84 mm..................1973 cc

84.5 mm................1996 cc

85 mm..................2020 cc

86 mm..................2068 cc

87 mm..................2116 cc

II. for the B18C (Stroke 87.2 mm)

Bore (Stock 81 mm)...Displacement (Stock 1797 cc)

82 mm................1842 cc

83 mm................1887 cc

84 mm................1933 cc

84.5 mm..............1956 cc

85 mm................1979 cc

86 mm................2026 cc

87 mm................2073 cc

Since, boring out makes the cylinder walls thinner and weaker in an open deck, the use of nitrous and forced induction is NOT recommended for bores > 85 mm , even if they are re-sleeved. Rules are meant to be broken but this is a general common recommendation at this time by people who build engines.

You are limited by how far you can bore to. The maximum bore on a B series is 87 mm. Why?:

The cylinders are siamesed meaning they are joined together. The "deep channel" between 2 cylinders is approx. 3mm thick. Once you bore past 6 mm above stock, you are into the next neighbouring cylinder. The walls are too thin. For race only "throw away" 10 pass blocks 87mm bore is fine but in road racing or street/race setups that need to last much longer, there's no point in pushing to 87mm bore.

III. Cylinder Wall Support and Re-Sleeving

Two common iron ductile re-sleeving manufacturers are Darton and Golden Eagle:

Golden Eagle


The CNC alignment prep is the important step to ensure precise clearances and fitment prior to the pressed-in installation of the sleeves. The supporting "tangs" are placed midway up the cylinder for buttressing, since cylinder wall failure usually begins in the middle and walks its way up to the top, unlike popular belief which states that the top of the cylinder needs the most support. The Golden Eagle sleeves allow coolant flow to travel up to the cylinder head and back to the radiator like stock . Therefore, unlike common cylinder re-inforcement (like the older version of the Nuformz blockguard , JG welded in spacer) which completely closes the deck and prevents coolant flow to the head, these sleeves do not have overheating or head gasket failures. The area near the combustion chamber is thicker to support at least 40 psi. However I do not believe Vince at GE would recommend overboring to the maximum 87mm for forced induced applications.




Darton is THE standard iron ductile sleeve manufacturer for Hondas. The deck, however, is completely closed off (temperature) and therefore, these sleeves are better for trailer queen drag racing Integras which work for 9-10 sec. only. Darton now has coolant ducts within their Honda sleeves.

Leitner & Bush (Canada)


Notice L&B's innovative approach similar to Darton's in which coolant ducts are added to the sleeve.

Posting Cylinders


Instead of using a blockguard or resleeving, some companies place a horizontal rod midway up each cylinder in the open deck space to buttress support the cylinders (8 posts on the intake side, and 4 on the exhaust). This is usually used in normally aspirated B18's with up to 85 mm bores. Again, the coolant is allowed to flow up to the head and back to the radiator at the same rate as stock.

Posted Cylinders by Endyn. Note the rods supporting the cylinder to the outer block wall place midway down the cylinder.

How To Post Cylinders by Larry Widmer at Endyn

It requires (using 12 ) aluminum rods (of the same alloy , cast 356, and heat treated as the block). The rod must be threaded. After calculating the points of maximum side force on both the primary and secondary thrust axis of the block (intake and exhaust sides, respectively), holes must be drilled through the block and threaded. We place two posts on the primary axis and one on the secondary axis to properly handle the loads (Intake side: 1.375" and 2.75". Exhaust side: 2.0")

The threaded rod should be cut into .625" lengths, with one end machined "dead flat" and the other slotted for a screw driver.

We sell the machined posts for somewhere around $36.00 per set of 12.

We (hand) tighten the "posts" to (no more than) 2 inch pounds (of torque) against the cylinders and we use Devcon liquid aluminum (not the aluminum putty) on the threads to seal them water-tight. If you weld them to the outer block the heat will affect the preload, distorting the cylinder.

re: why 8 posts on the intake side and only 4 on the exhaust side?

The intake side is the major thrust axis, so the piston is really trying to shove itself through that wall when you're really cookin'. There's no reason not to put more posts in the exhaust side...

...I recommend doing the procedure prior to any cylinder machine work taking place...

Posting began years and years ago with NASCAR engines that had blocks with thin cylinders, by design, or due to core-shift. I used to also post every iron BOSS 302 and BOSS 351 head I ever did for Trans AM or NASCAR to prevent the waterlackets from raising up and blowing head gaskets. We used to also post iron Big Block Chevy heads for extreme pressures associated with driving the "pumps" on jet-drive drag boats.

Posts allow you to connect two walls without blocking substantial coolant flow, which is very important.

We don't weld the posts in place because the heat of welding would shrink the posts, so they wouldn't have the proper pre-load from installation. If you increase their diameter and mass, they will expand more as the engine heats up, so the shape of the cylinders at operating temperature may not be anything like the shape they were originally machined to.

You'll need to experiment with larger posts to actually determine what the effects of heating will be on the concentricity of the cyinders, remembering that ring seal is "everything" on a high performance engine.

DART/Payn Technologies Complete Big Bore Blocks


Or you can sell your Honda block and buy a complete ductile iron block with the bore sizes you want and with steel main caps from Payn Technologies. The come with the same deck height as any B18 or B20 and you can also order one with up to 0.55 in. or 13.97 mm more deck height for a longer rod.

AEBS T-Sleeves


featuring three-dimensional supports that greatly reduce dynamic side loading commonly experienced by conventional replacement sleeves. AEBS T-Sleeve with solid deck technology provides unsurpassed head gasket surface sealant area. All sleeve work comes with matched cooling ports to the factory head gasket. This ensures optimal cooling efficiency for both the cylinder head and block. Engineered for Naturally Aspirated, NOS, Turbocharged and Supercharged engines.

Same material used in top fuel cars.

Successfully tested to 55 lbs. of boost.

2b. Mixing and Matching Bores and Strokes

Some people try to get 1.9-2.0 L displacement from a B18 by mixing and matching with other B Series Honda parts.

I. General Rules To Remember

I'd like to thank my friend Tony who helped me sort out the "rules" for the various parts which can be mixed and matched.

a) Rule 1: Any B series Honda crankshaft will fit in any B series block (with minor machining or notching to allow for adequate clearances in some cases).

b) Rule 2: Any B series rod will fit any B series crank, EXCEPT the B18C's and B16B (CTR) { i.e. "R" family: ITR, GSR, CTR}.

The B18C1, B18C5, and B16B rod are 1.96-2 mm narrower (0.858 in. vs. 0.935 in. in non-R rods) at the crank end (or rod "big end") and will not fit on the other Honda B series cranks or pistons.

On the small end of the rod (from FF Squad):


Rod Small End Widths:

B18C1, B18C5 17.9 mm (0.705 in.)
B16A, B17A 18.0 mm (0.710 in.)
B18B 19.9 mm (0.785 in.)
B20A 23.7 mm (0.935 in.)

Here are the Strokes for each B Series Crank :

B16A and B16B............77.4 mm

B17A.....................81.4 mm

B18C1 and B18C5..........87.2 mm

B18 A/B and B20B/Z ......89.0 mm

B20A.....................95.0 mm

Remember, rod ratio is the connecting rod length divided by the stroke.

One way to get a higher rod ratio (i.e. get higher revving ability safely without sideloading the cylinder walls too much or getting more vibrations) is to reduce the stroke ( by swapping to a crank with a shorter stroke) .

The other way to get a high rod ratio is to use a longer rod. Three of the longest stock Honda rods are:

B18A/B or B20B/Z 137 mm

B18C's 137.9 mm

However, using a longer rod or increasing the stroke usually means you have to add deck height.

LS owners who were wondering which rods fits their crank without any machining needed? Answer: B16A, B17A, B20.

The B17a rod length is the shortest of the three at 132mm.

The B16a is next at 134mm and the B20 rod is 137 mm in length.

The longest B-series stock rod is from the B21A (early 90's Prelude) with a 141.7mm rod length.

c) Rule 3: Any B series piston will directly fit onto any B series rod without milling or machining , EXCEPT the B18C's and B16B {i.e. the "R family" of rods} .

The connecting rod bearing width on the B16A,B17A, B20B/Z, and B18A/B is apporoximately 19.5 mm. The connecting rod bearing width for the B18C1, B18C5, and B16B is approximately 17.5 mm (ca. 1.4-2mm narrower at the crank). The same narrower width happens at the small end of the rod. The B18C small end width is approx. 2mm narrower than the other Honda B series rods' small end width.

LS owners who want more compression, you can this from a B16A and B17A piston and it is a direct fit at the piston pin to your rod.If you want to put a narrower B18C piston onto your rod, you must mill 1 mm off each side of the rod at the small end to fit.

d) Rule 4: Block Deck Height

is the main reason you cannot go for a "drop-in only " longer rod or stroke. You can calculate whether your new rod length or stroke will exceed the deck height from these numbers:

Block Deck Height = (Stroke/2) + Rod Length + Compression Height + Stock Deck Clearance

B18A/B and B20B block deck height = 211.84 mm

B18C1 and B18C5 block deck height = 212.39 mm

B16A block deck height = 203.37 mm


e) Piston to Deck Clearance

B18A/B, B18C1, B18C5, B20Z/B = 0.76-0.84 mm ( 0.030 -0.033 in.)

B16A/B = 0.5-0.9 mm (0.020-0.035 in.)

f) Piston Compression Height

B18A/B (PR4) 29.97 mm

B18C1 (P72AO) 30.05 mm

B18C5 (P73AO) 30.23 mm

B16A (PR3) 29.97 mm

B16B (PCT) 30.73 mm

B20B (P3F) 29.59 mm

g) Piston Dome Height

B18A/B (PR4) - 1.397 mm

B18C1 (P72AO) 0.00 mm

B18C5 (P73AO) + 1.78 mm

B16A (PR3) + 2.49 mm

B16B (PCT) + 6.43mm

B20B (P3F) - 0.89 mm


Now that the rules are known, what can we do to mix and match to get 1.9-2.0L (i.e. more displacement for power)?

You cannot use a B16A or B16B crank to achieve 1.9-2.0L. Even if you bore out to 87 mm, the displacement is only 1840 cc.

This leaves us with the remaining cranks:

I. B17A Crank (IF you can find one)

You will need to bore out to at least 86 mm to get close to 1.9L (1891 cc). Boring to 87 mm (max.) will get you 1936 cc but reduces your reliability. Using a compatible, direct-fit LS B18A/B rod onto the B17A crank, the rod ratio will be a very good 1.68.

II. B18A/B or B20B/Z Crank

For the B18A/B block, you will need to bore out to at least 84 mm to get close to 2.0L. If you do not want to re-sleeve, then a bore of 82 mm will give you close to 1.9 L (1880 cc). Most people opt for 84.5-85 mm bore to get 2.0L (1996-2020 cc) . You can do this by boring and sleeving a stock LS block or honing a stock B20 block (stock bore is already 84 mm!!!) to 84.5 mm (cheapest way to go).The rod ratio remains stock with 137 mm long stock rods at 1.54. There is no advantage to using a B18C rod, since this only increases the rod ratio to 1.55 and you'd need to add 0.9 mm deck height.

III. B18C Crank

You will need to bore out to at least 85mm to get close to 2.0L (1979 cc) and 83-83.5 mm to get close to 1.9L (1887-1910 cc). You'll have to re-sleeve anyway, so you might as well go whole hog with 85 mm. The rod ratio remains at 1.58.

3. Swapping for a B20B/Z or H22A

I. B20 Swap

The cheapest way to get 2.0L is swapping for a CRV engine (84mm bore x 89 mm stroke) completely in the case of LS/SE owners . Some blocks may need to be aligned honed and in some cases where you plan to rev the block past 8000 rpm, you'll need to add a block girdle similar to those seen on the B18C's or an aftermarket girdle for reinforcement of the block's mains.

The cheapest way to get 2.0L for GSR and ITR owners on the other hand is to bore out to 84.5-85 mm and purchase 84.5-85 mm off the shelf pistons.

LS/SE owners can source out the cost of getting a CRV block and trying to locate any VTEC head. The VTEC heads will need to have their bowl bored to the same bore as your B20 block (called "spot facing") and deshrouded around the valves. You will get more quench area by doing this as well. Like an LS/VTEC you will have VTEC on a non-VTEC block except now you have more displacement with a B20 over an LS/VTEC.

If you don't have your heart set on more displacement, the permutations and combinations are numerous. You just need to make sure the rods fit the piston and the crank, check that everything will fit in the deck height of the block you choose, and calculate the resultant displacement and rod ratio. As a popular recent example, many people try a B16A crank (77.4 mm stroke and the mains can be align honed for better bearing crush) with LS rods (137 mm rod length) in a CRV block (84.5 mm bore when bore-honed) with a GSR block girdle added to give a strong 1736 cc, an oversquare layout, and a 1.77 rod ratio. You essentially build a 1.7 L Civic Type R Plus engine in your LS Integra that can rev like a bike.

I won't delve into how to build a B20-VTEC, since www.b20vtec.com covers this in much greater detail.

II. H22A Swap

Another way of achieving 2.0L or more in an Integra is to swap for an H22 engine, ECU-VTEC wiring harness, and tranny.

The downsides are :

a) The H22A and tranny will add at least 100 lb to the front of your Integra compared to a Bseries engine and to some people this is not important. However, the polar moment of inertia (i.e. how easily the car will turn/spin based on weight distribution) is drastically changed and the cornering speeds will be reduced since you won't make turns as fast without ploughing forward with understeer.

b) you will lose your A/C and power steering (or relocate the A/C) to make room in the engine bay for this engine and tranny.

c) you are stuck with the H22 tranny. Unlike the B series where you can mix and match stock trannies with different gear ratios, final drives, and LSDs, you have only 1 choice.

If these are not a big deal to you then the same rules for putting an H22 into a Civic apply. For 3rd generation Integra owners, you will need either a 90-93 Accord left side axle intermediate shaft with a 90-93' Integra left axle or you can use both 90-93' Integra driveshafts. The best way to go is to purchase stronger aftermarket driveshafts made for the Gen.2 Integras from someone like Frank at

http://www.driveshaftshop.com/vtec.ivnu (whose product I have personally used and highly recommend ) or

http://www.raxles.com (who also come well recommended by fellow racers)

You will need a HASPORT or PLACE RACING mounting kit and basically will need to shave off the tranny side mount bracket. There's no need for the top tranny mount bracket, since it bolts on from the bottom of the frame.



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