B20z is the usdm high comp.
Google b20 and there’s a site by hybrid performance and they compare the low and high compression b20s on the dyno.
Soon when my near stock B17 goes (it’s nearing 190k) I will swap a high compression in with the short geared ys1, should be fun around town, 20ft lb increase!
b18 is better IMO. Higher compression is always better, plus the B18’s are stronger. The only reason you would need low compression is if your running a cheapo tuning setup on a boosted motor I.E. chrome. Low compression gives the tuner more room for error, but makes less power in the long run. So long as you have a solid tuning system and tuner higher compression will yield more torque, which means more power.
plus B20’s are weak overall, i have seen many fail.
[QUOTE=DA9_BoostKING;2252951]b18 is better IMO. Higher compression is always better, plus the B18’s are stronger. The only reason you would need low compression is if your running a cheapo tuning setup on a boosted motor I.E. chrome. Low compression gives the tuner more room for error, but makes less power in the long run. So long as you have a solid tuning system and tuner higher compression will yield more torque, which means more power.
plus B20’s are weak overall, i have seen many fail.[/QUOTE]
On what basis? You realize that a b20 and a b18 block, rods, pistons, components are all virtually the same other that measurments. Failure of any b series build can be a result of any number of factors. Simply being a b20 does not mean u have a weaker engine setup at all. that’s completely false information. at this point tehre are just as many guys who run b20 swaps, and builds, and b20vs as simple ls setups and have no problems. there are tons of turbo applications, spray, and all motor apps. one is no stronger than the other.
The B20 is weak because of the cylinder walls, they are thinner then all other B-Series and more prone to failure. They are also 1-piece constructed as opposed to B18’s/B16’s where they are individually pressed in. The B20 can be a monster but only after it’s been sleeved. I have built several on stock sleeves and have seen them fail over and over again due to the stock sleeves cracking or being ran out of bore. I have yet to have a B18 sleeve crack on me.
While that’s true that the walls are thinner it’s not by much, and yes the are a one piece construction, but again not the primary reasons most crack. MOST crack due to lack of knowledge when building a motor to rev, improper tuning, and excess revving (like for example the 1=2=1 shift error overreving the engine and causing the sleeves to crack). There are just as many instances where b18 and b16 sleeves have failed for all the same reasons. There are PLENTY of monster UNSLEEVED all motor, turbo, sprayed, and supercharged b20 blocks floating around all over the country, running hard with 0 issues. Endyn has put together many without sleeving them for endurance and track duty, and they don’t have any problems. The b20s “weak” point in the sleeves do not single it out as an inferior choice when building an engine.