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im getting ready to do my ls-vtec conversion here in a few months. i have a b16a1 first gen motor and i was wondering if anyone has used b16a1 pistons and rods with lsvtec ? just wondering what internals are recommended for all motor lsvtec.
 

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what would be the use of the ls motor if you did that? also the bore is different on the ls block as well....the rods and pistons will just lower the displacment
 

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Not to mention all the cutting and welding necessary to do so. If I were you I would hold off on the LS/VTEC engine for a while. You need to learn more.

What's the point of swapping the b16a1 internals into the b18b when you already have the whole gitup standing in front of you? Do you know how LS/VTEC works? You combine a low rod ratio bottom end with a small port volume head. This makes an engine package that likes mid-range rpm torque. This is similar to old domestic hot rodder engine packages: low-rod ratios and small port volumes which create a lot of low to mid range power, but cannot rev high due to the low rod ratio. IF they could rev high then they couldn't make power way up top because of the small port volume. The ports would "run out of breath" way up top.

See how engine pacakges work?
 

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ITR41 on Sep/19/02 said:
what would be the use of the ls motor if you did that? also the bore is different on the ls block as well....the rods and pistons will just lower the displacment
this is not correct...

all of the b series engines, except for the b20, have an 81mm bore stock . Honda also makes 81.25mm oversized pistons as well for these bseries engines, if you need to straighten out the walls by mildly boring only 0.25 mm, when you have to replace the piston rings. This is not the same as the radical boring out we do to get more displacement and need to resleeve the cylinder liners. The oversized 81.25mm Honda pistons are just for those people who have warped walls or have deep scores in the walls and need to straighten them out before replacing the rings for a good seal.

the displacement would not change, since he is still using a b18b crank with the same stroke (89mm) and the bore (81mm) has not changed.

guessing can lead to bad advice.

divide the bore and stroke by 10 to convert from mm to cm. then,...

displacement in cubic cm (cc) = bore x bore x stroke x 3.14159

remember , 1000 cc = 1L displacement .

to convert to cubic in. divide the cub. cm (cc) by 16.387.

the displacement calculated here represents the TOTAL displacement or sum of the 4 cylinder's displacement. To get each cylinder's displacement divide by 4.


you can use b16a pistons in a b18b block and they fit on the small end of the b18b con rod without having to mill them. the static CR would be a healthy 11.5:1 using P30 pistons and 11.3:1 using PR3 pistons .

you don't want to use the shorter b16a rods (length 134 mm), since the b16a block and deck heights (203.37 mm) are lower than the b18b's block (rod rod length 137 mm, deck height 211.84 mm ). the r/s with b16a shorter rods and the b18b crank is 134/89 = 1.50...less than the stock b18b 1.54 r/s!!!

if you did indeed want to improve the rod ratio on the b18b by using the b16a crank (r/s= 137/77 = 1.78), you would also have to deck the block (remove material off the block's deck) to allow the pistons to travel to correct height at TDC in the chamber...this decking of the block would retard cam timing as well.

the displacement drops to 1587cc though with a b16a crank. you'd need at least 85-86mm bore to get back some of that displacement closer to the original 1.8L (1748-1789 cc). that requires resleeving the block (kaching, kaching).

you would need to use new Honda rod bearings and new ARP rod bolts.

this is why it is cheaper to go with B20 block right out of the box instead of the LS/VTEC. no boring out, no new crank, no decking the block. just hone and get 84mm bore pistons, connect the oil T line for the VTEC solenoid, and align the dowel pin holes.the r/s is 1.54...not 1.50 and you have 1972 cc (say hello to Mr. Low-Midrange Torque).
 

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APG_LsVtec on Sep/19/02 said:
yo i used ITR pistions on my ls rods.. use b18 rods or go all out and stroke it to a 2.0..what head internals will you use?
WTF? Why would would want to stroke it to 2L? The B18b already has a 1.54 rod ratio, do you have any idea what stroking will do to it?
 

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Stroking it makes it hard...Yo!


Mike: I'll go one further... get custom rods to make up for the difference between the strokes and add it on to the rods. cheaper then decking and better ratio!

AllMotorNonVTEC: go to www.diyracing.com and check out the LS/VTEC headwork required. also do a SEARCH on this site. keep the ls bottom end, take the oil and h2o pump off of the b16a, use the b16a pistons, and get a vtec (b18c) timing belt. the Vtec H2O pump has a different tooth count which reqires the vtec timing belt. use a b18a/b head gasket
those are just a few quick suggestions.
 

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hee hee are you ready for this one mike??
ls block with ls pistons, b16 crank, custom rods (143mm) and standard bore:
- rod ratio 1.857 (!!!)
- displacement 1587 cc's

Ls block with the above but bored out to 87mm (yikes!):
- displacement 1831 cc's (hey...!)


moral of the story...
b16 cranks suck.
 
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