B20vtec Reliability Factor

[Canuck 93 Civic Si]

I just finished reading an article on another site about how the B20 and LSVtec are evil because of the low r/s ratio generally associated with these engines. Could you use a bit smaller crank to lower the stroke, longer rods to get back compression and bore out the block to compensate for the lower stroke and still have 2 liters and a better r/s ratio ? Or is this all wrong and not possible by any stretch of the imagination ?

Also, is the unreliability factor that everyone talks about even that bad and maybe a little exaggurated ?

Im considering the swap but the car is also my daily driver and it must be reliable.

Thanks

 

[prawjEKt Cx]

ok r/s unreliability..... ok if ideal r/s is 1.75 and a b16 block is 1.74, then that's pretty damn perfect, but when you get down to it as the ls being shit because it's 1.54 remember the gsr is only 1.58

 

[Canuck 93 Civic Si]

Good point, but could you improve it a little with the above mentioned mods?

 

[prawjEKt Cx]

Originally posted by Canuck 93 Civic Si@Jan 6 2003, 08:18 PM
Good point, but could you improve it a little with the above mentioned mods?

well i've never tried anything of the sort, but in theory it sounds like a good idea. but what Bseries honda block consists of rods larger than that of the b20, what i'd do is get a b18b with Golden Eagle Godzilla sleeves, 84mm, so you'll have your 2 liters, and i'm sure they can handle a little piston beat, not to mention a assload of boost

 

[asmallsol]

Hybrid engines like the CRVtec and LSvtec are only "EVIL" when put into the wrong hands. If you just slap a Vtec head on the thing then drive off reving to gsr redline, yes they are EVIL but if you dont half ass the swap, it is just as relibale as any swap. Look at calesta with his CRVTEC, over 40k miles with no incident (except for him chewing up a set of rings when he over reved it like a week ago) Click on his sig and also read the faqs and articles about that engine. I think that he ended up usings a b18b crank.

This swap is one of the hardest swaps for a honda and is not for the novise, (unless you got money to have someone else do the entire thing) You have to completely rebuild the engine including the rods and internals like that. Also it is strongly advised that you replace the sleves with something like golden eagle sleves.

 

[Canuck 93 Civic Si]

Thanks for the input. I checked calestas site and it doesnt mention resleeving but was his block resleeved? Ive read the FAQs on this site and many others. The only reason I dont read them much any more is because I find it rather repeatative after a while. I am still however looking into the specifics of the B20 and other higher end swaps. I dont like to think of myself as a novice but im not going to run around braging about my mechanical prowes either, that would be dumb. As for cash, I am in shool right now ( for aircraft maintenance engineering or airframs and powerplants as the yanks call them ) so needless to say, not the richest person in the world. However this summer I am going to be working at an aircraft maintenance facility somewhere near pearson and that is when I plan on begining work on my new engine.

 

[asmallsol]

since you said that your in school right now to be a aircraft maintenance engineer i guess that means that you have a decent understanding of this kind of stuff. About Calesta sleaving his engine, i am 99% sure he did, he is running over 12:1 compression. He ended up going to intercrew autosaloon (something like that) to do his swap and they built the engine for him, cost him about 6k. For what he got, i think that it is a great deal, way power than a ITR but yet only 1-2k more and if you buy cams for the ITR then you are already past the amount that you spent on the crvtec. This is the faq that i was talking about

 

[lsvtec]

Calesta did not resleeve his engine. If you want to run NA there is no reason to. The B18B crank and the B20b/z cranks are exactly the same so he didn't make a change there. The B20b/z get their extra displacement from a 3mm larger bore over the B18a/b. You can use a different crank to change the R/S ratio of the LSVTEC/CRVTEC but there is no need to. The person that wrote that article knew just enough about engines to be dangerous to anything he touchs, but not enough to make an informed or even intelligent opinion. I have direct experience with 2 LSVTEC's (mine and a freind of mine's) and indirect experience with one CRVTEC (calesta's). Calesta's engine was put together expertly and he has not had any problems related to the engine (beyond the over rev). My engine burns a little oil because I did not seat my rings properly, and my friends has had no problems in the year and a half it has been running.

Cliff notes: All of the articles saying that the LSVTEC is *evil* because of R/S ratios are bunk. Built correctly they are just as solid as any other swap, more solid in some cases.

 

[K2e2vin]

Another thing is the B20's single piece sleeve. Because of this wouldnt it be better to just get a B18c5 and bore it to 84mm? Ive figured out ways to improve the B20/VTEC, even found a pretty good crank and rod combination of 1.7537 and another one at 1.68. I am lookin to rev to 9k or higher (if possible). It is the sleeve thing that concerns me, after hearing of some people cracking them.

 

[prawjEKt Cx]

Originally posted by K2e2vin@Jan 7 2003, 04:35 PM
Another thing is the B20's single piece sleeve. Because of this wouldnt it be better to just get a B18c5 and bore it to 84mm? Ive figured out ways to improve the B20/VTEC, even found a pretty good crank and rod combination of 1.7537 and another one at 1.68. I am lookin to rev to 9k or higher (if possible). It is the sleeve thing that concerns me, after hearing of some people cracking them.

what's your crank/rod combo,please share.....

 

[Canuck 93 Civic Si]

yes please share. Does this combo also allow the displacement to maintain 2 litres?

 

[K2e2vin]

The one with the 1.7537 R/S ratio is I found out later doesn't work. It is using a B17 crank with B20A(prelude) rods, but that inteferes with the head. The one at 1.683 R/S is also using the B17 crank but with the b20b rods. They are around 1970cc with the head (b16a) and regular b20b pistons.

 

[lsvtec]

Calesta has run his stock B20 crank with Eagle B20 Rods and has revved to 8500 regularly without any bottom end problems. The R/S ratio of the LS/CRV engines is not bad enough to worry about for revs < 10k. With the proper bottom end parts you could see 9k regularly with a 1.54:1 R/S ratio.

 

[prawjEKt Cx]

Originally posted by K2e2vin@Jan 7 2003, 07:49 PM
The one with the 1.7537 R/S ratio is I found out later doesn't work. It is using a B17 crank with B20A(prelude) rods, but that inteferes with the head. The one at 1.683 R/S is also using the B17 crank but with the b20b rods. They are around 1970cc with the head (b16a) and regular b20b pistons.

i should really get off my ass and do some math, but oh well you answered it for me.... thanks

 

[phunky.buddha]

Originally posted by lsvtec@Jan 7 2003, 07:07 PM
Calesta has run his stock B20 crank with Eagle B20 Rods and has revved to 8500 regularly without any bottom end problems. The R/S ratio of the LS/CRV engines is not bad enough to worry about for revs < 10k. With the proper bottom end parts you could see 9k regularly with a 1.54:1 R/S ratio.

Yup. Thanks for speaking all the correct info for me while I've been out during my move and transition to Dallas.

Resleeve = no. I'm running the stock sleeve.

Revving to 8500 = no problem. Just don't downshift to third from fifth and pop it to 8800rpm in a flash... that'll damage most any engine, regardless of geometry. I'll be revving to 9k and more with a girdle and new valvetrain, so don't think it can't be done.