Killer B's.... Mass LS/VTEC info!!!

TeggyBear_Ls

90 EF LS/V 95 DC4
So, this article was in an old 2002 Honda Tuning magazine.... I've only slected a small portion of the article on Frankenstein Or more commonly known as LS/VTEC conversions... Enjoy the read! 8)

" Perhaps the biggest bang for buck is a Frankenstein engine. A Frank is a bunch of swaps between different blocks and heads within the B engine family to make some non-factory combinations that work exeedingly well.
-The most popular Frank swap is adding a VTEC B16A or B18C head from a delSol, Civic Si or an Integra GS-R to an LS non-VTEC Integra B18B or even, to make a really big engine, the mini-SUV CRV B20B or B20Z bottom end... The common, easy to find LS Integra B18A and B18B engines have a bore and stroke of 81x89mm, which gives you 1834cc. Powerful but expensive in salvage yards, the VTEC enhanced B18C has a 81x87.2 bore and stroke, which gives you 1797cc of displacement. The smaller but powerfull B16A has a bore and stroke of 81x77.4mm for a displacement of 1595cc. By putting the VTEC head onn the LS bottom end, you pick up 35cc over the B18C and a whopping 239cc more torque-producing displacement over the B16A. The added displacement and stroke give the LS Frank engine a nice torque advantage.
-Due to the B engine's exellent interchangeability, you can put a B16A head, a B18C head, or even the expensive and rare B18C5 head from an Integra Type-R on the LS bottom end to make a larger displacement, longer stroke, potent torque monster B18. It has the best of both worlds, the torque of the B18B or B18A with the screaming VTEC power of the B18C. This head swap adds about 40hp to your typical LS engine with naturally aspirated wheel hp figures in the 170-190hp range and torque in the 120-145 lb-ft zone easily with 91 octane pump-gas. The engine will retain a compression ratio of approximately 10:1 with this combination of heads.
-To add a VTEC cylinder head to an LS bottom end, you must tap and plug the VTEC oil supply hole found on the bottom left side of the head. A 1/8-inch pipe plug will work well for this. Next you must run an oil supply line from a T-fitting placed on the oil pressure sending unit boss on the block to the VTEC oil galley plug found on the intake side of your head near the distributor. To make the oil line, you need a piece of -4 braided steel line about 20-inches long, with two female A/N fittings attached (an industrial hydraulics shop can make this for you), a 3/8-inch NPT to -4A/N adapter for the head, a 1/8-inch NPT to -4A/N adapter and a 1/8-inch NPT T-fitting with two female sides and one male side.
-You must also open up the dowel pin holes on the VTEC cylinder head to a 9/16-inch as the LS block has larger dowel pins to locate the head on the block. This is a pretty simple operation that can be performed on a drill press. If you don't feel like doing this, the operation can be easily handled by any compentent machine shop.
-An LS head gasket is used with the appropriate VTEC ECU for your year and chassis of vehicle. A jumper wire running from the appropriate pin in the ECU for the VTEC control solenoid completes the VTEC activation. The proper VTEC ECU is the ECU for the VTEC model of your vehicle. Below is a chart with the pin locations where the wires to control the VTEC solenoid connect...
-It is also critical to hook up the knock sensor or the VTEC function will not work. The engine's ECU looks for the knock sensor signal in order to activate VTEC. The B18A and B18B block has no provision for a knock sensor. In this case, or if you don't want to run a knock sensor, you can do several things. You can have a knock sensor not attached but grounded to the chassis and connected to your ECU, or Hasport has ECU's that are reprogrammed to allow VTEC operation with no knock sensor input.

B18 INFO DONE, NEXT IS THE B20/VTEC INFO

- Another very potent Frankenstein combination is using the B20 bottom end from the CRV mini-sport utility, with a VTEC head. The B20 bottom ends that are desireable are the B20B (97-98 CRV) and the B20Z (99-01 CRV). With a big bore of 84mm and a stroke of 89mm with a whopping displacement of 1973cc, a B20 Frank has the potential to be the meanest of all of the Frank engines... Of the two engines, the B20Z has more compression at 10.2:1 over the B20B'S lower 8.8:1. This is because the B20Z has a flatter top piston when compared to the B20B's deeper dish. The lower compression B20B is more desireable for a bolt on supercharger or turbo because of this. You cannot use the standard piston for high compression N/A on the B20B orZ. Many companies will make you a high-compression piston though.
-The preocedure to swap a VTEC head on the B20 is the same as the LS swap with the exception of using the B20 head gasket. A N/A, mild B20 can easily get more than 200hp on pump gas with more than 150 stump-pulling torque. As a warning, when the VTEC head is installed, theres not a whole lot os piston-to-valve clearance as VTEC heads have larger 33mm intake valves VS. the B20 engine's 31mm valves. If you are dyno tuning, contact will occur between the piston and valves if the cam is advanced much more than 4 degrees, so be careful. In fact, this is so close, it's not advisable to advance the intake cam at all. "



Well, I hope you enjoyed this long read...... Took me awhile to type it all out Lols....
 
Last edited:

skoodles

I <3 Vanessa
i learned something i didn't know and i did lots of research on b20/ls/vtec about the valves being bigger on the vtec head and not advacing cams at all with stock b20 pistons because of clearance. good info
 

B16B_civic_R

do U <3 your Honda
i learned something i didn't know and i did lots of research on b20/ls/vtec about the valves being bigger on the vtec head and not advacing cams at all with stock b20 pistons because of clearance. good info
yup thats why companies like JE make forged high comp. pistons specificaly for B20/v motors...so you dnt have to worry about piston to valve clearence issues
 

TeggyBear_Ls

90 EF LS/V 95 DC4
Yeah, you can get companies to make you B20/VTEC pistons. I think the article said it's around 11:1 comrpession on the b20/vtec with pistons
 
Top