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boi-alien
05-24-2002, 11:19 AM
i was just wondering, if anyone out there has built one of these hybrids. my friend and i were thinking about building a couple of these engines but we weren't sure of the specs on the engine. if anyone out there has one of these engines, and knows the specs on it, ie. what parts we should get b16 head or b18 head, things like that, could u please give us a hand? thanks!:D

redline
05-24-2002, 11:50 AM
i would use a b16a1 head. Cheapest and they are all the same. (except for GSR heads) And a block of your choice. b18 or b20. Depanding on the car will tell you want bottem end to use.



Personally i am not a fan of these setups. It takes a lot of work to set them properly. And i am not sure how reable they are at the end of the day. If done right it is almost the same money to do a vtec engine out of the box.

Talk with Alan at Auto-Zeal or nelson at tunerworks both have experence with these.

boi-alien
05-24-2002, 12:56 PM
hmmm sounds good, we're going to put them into a CRX, and a del sol. i read really awesome reviews on these engines though.

mostly i'm impressed with the torque numbers on these engines! cause we all know that honda engines are very torque deficient. well i was thinking of getting a GSR head actually, but i was wondering if it made a difference at all if i got a B16 head instead.

i've talked to neslon a couple times on the phone. are nelson or alan on here??

redline
05-24-2002, 01:14 PM
It is not worth the price difference in the head. Stock vs stock a GSR head out flows a b16 head but ported the b16 head more flow potential.

I would a use a b18a bottem end in the CRX and a b18b or b20 in the del sol.

CRXguy
05-24-2002, 04:05 PM
I'm been wanting to go with CRVtec for a while, but it's too complicated and some "Frankenstein" engines don't put out the power they're suppose to.

B20 + FI = :thumbsup:

redline
05-24-2002, 04:27 PM
Originally posted by CRXguy
I'm been wanting to go with CRVtec for a while, but it's too complicated and some "Frankenstein" engines don't put out the power they're suppose to.

B20 + FI = :thumbsup:

or last.


I would suggest using a GSR engine sleeve and bore it to 2.0l and have a more reliable higher reving engine.

boi-alien
05-24-2002, 07:22 PM
yea that's what i was thinking of doing a b20 with FI!!! hehehe should be quick

boi-alien
05-24-2002, 07:23 PM
so no b20b in the crx then eh?

legendboy
05-25-2002, 12:00 AM
Originally posted by redline
It is not worth the price difference in the head. Stock vs stock a GSR head out flows a b16 head but ported the b16 head more flow potential.

I would a use a b18a bottem end in the CRX and a b18b or b20 in the del sol.

Ok, first of all, the B16 head is the BEST FLOWING B series head honda has ever made, Stock. It flows better than ITR head. Second, do any of u know why one might use a b20 bottom end over a b18 bottom end? The B20 and the B18 are exactly the same block becides the fact that the B20 is 2.0 L and has a longer stroke than the B18. IT DOES NOT make any difference which block u use for a swap on any car, the install is exactly the same. Now, why is the crvtec a good choice? By using the B20 bottom end you have 2106cc's and long stroke. That is where the torque comes from. The B18 is ok but the b20 has alot more possible torque potential at high revs than the b18. The r/s is very long so the reliability factor comes into play when u figure with a b16 head ur going to be pushing the engine up to or past 8000rpm, without using forged rods, arp rod bolts..etc...and idealy a sleeved block there is a good chance of putting the pistons thru the cylinder wall. This is the secret of a good hybrid engine IMHO. The b20's r/s is 1.54 (i think) and the b18's r/s is 1.58. So a longer stroke coupled with larger displacement and high revs of the super good flowing b16 head = easy 210+whp, with boltons, proper engine management and GOOD tuning. Crvtec engines consistantly output more power than ITR's, and have gobs more torque.

boi-alien
05-25-2002, 12:11 AM
yea, that's what i heard about crvtecs. and i'm just totally blown away at the torque numbers. and i mean, that's what we all want when it comes down to it, torque is what gets u going, hp just keeps you going afterwards

redline
05-25-2002, 12:35 AM
Originally posted by legendboy


Ok, first of all, the B16 head is the BEST FLOWING B series head honda has ever made, Stock. It flows better than ITR head.


Please provide flow charts for this.

And could you tell me the difference between a b16 , b17 , and b18c5 heads?

legendboy
05-25-2002, 02:31 AM
Here it is......

there arn't too many differences in the heads, becides a little different cylinder head volume, GSR is 41.6cc and b16 is 42.7.(b16 has a bigger combustion chamber) The valve sizes are exactly the same. The B16 head will give a bit higher c/r than b18c1, b18c5. The advantage of the b16 head and its flow charicteristics *spelling* is that it will create more mid range power than the gsr or itr, and the b18c head will give u a bit more power at say 7900rpm or right at redline. There is also the issue of cams. Using ITR cams in the b16 will yield different results than using CTR or stock cams, its the same story, where would u like to make power? Power at redline is pretty useless compaired to nice midrange power...
http://alaniztechnologies.com/images/b16vsgsrstock.jpg

boi-alien
05-25-2002, 03:13 AM
hmmm very interesting. yea redline power isn't as great as midrange. midrange power is where it's at especially when i want to be able to do auot-x as well as drag racing. legendboy, what about the throttle body, i've heard that i should use an ITR throttle body. and keep in mind that i'll be slapping on a turbo afterwards.

legendboy
05-25-2002, 10:33 AM
Originally posted by crxboi
hmmm very interesting. yea redline power isn't as great as midrange. midrange power is where it's at especially when i want to be able to do auot-x as well as drag racing. legendboy, what about the throttle body, i've heard that i should use an ITR throttle body. and keep in mind that i'll be slapping on a turbo afterwards.

That makes sense but the amount of power generated at high rpms with a b18 head is not very much more than the b16 head, say 5whp. But the amount of midrange power created by the b16 over the b18 is quite a bit. Say 10 or 15 whp.

If ur slapping a turbo on I'd use a stock b18 or b20, non-vtec. I'd go ls-turbo.

redline
05-25-2002, 11:08 AM
well you are right about some stuff.

First off the question on the heads that you did not answer. The b16, b17, b18c5 head are ALL THE SAME. ONLY THE B18C1 (GSR)head is different.

You need to learn what they are doing when flowing a head cause you are little off and flow numbers only tell part of the story. And lift does not equal RPM. so that has nothing to do with mid range power.

You have to look at manifolds, valves, cams, headers and trannies to determine the a more complete setup.

Although what you say is true on the volumes, the pistons in the engines are different and the interaction between the two is more important.

Valve sizes are the same but the shapes of the valves are differnet in the heads and this greatly affects power more then size.

boi-alien
05-25-2002, 12:48 PM
Originally posted by legendboy

If ur slapping a turbo on I'd use a stock b18 or b20, non-vtec. I'd go ls-turbo.

why the non-vtec legend boy?? and i don't think the B20 block will fit in my car if i didn't get a different head. i've been told that the B20 head is too tall to fit in my car.

Daddymax
05-25-2002, 06:45 PM
Baron. I wouldn't go that route. Before I dropped my engine I was set on LS vtec.

I did hours upon hours of research. Talking to people in toronto how had that engine and everything.

First of all when you look at B18's and B20's they dont' rev like b16's or Gsr's. So the bottom end isn't really built for the high RPM's.

B18's and B20's Don't have the oil squirters for the pistons like the ITR and GSR's .

If you build it right the motor can be powerfull and semi safe. But in the end it's going to cost your TONS. I would say 5000- 6000 installed. IF you want it right that is.

You could cheap out but then it might blow in 2 months or it won't be much more powerful than a B16a.

legendboy
05-25-2002, 08:07 PM
Originally posted by redline
Stock vs stock a GSR head out flows a b16 head but ported the b16 head more flow potential.

I guess we are both wrong about some stuff:dunno: , the statement above is definatly not true, and since the b18c5 head is a b16 with a mild p/p, I'm pretty sure I was wrong in what I said. The b16 has a reputation for being the better head overall for this setup. It's true that the b16-17 are the same but the b16 head will perform better with the stock b16 cams than the b17. I'm almost 100% about that. When I'm talking about head flow, I am not really refering to having the head flowed on a bench, I am talking more about how it performs with the rest of the engine, stock cams included.
Using an ls block with usdm or jdm b16 pistons, which head is the best to use? The b16, b17, b18c, b18c5? (ls/vtec or crvtec motor) Which head is the best to use? Now, if I had the dough, I'd go with jdm itr head just cause:thumbsup: , next b16.

I'm glad that there are some peps here that know all about this stuff, sometimes the tech posts are pretty boring!:)

EDIT: BTW Daddymax, ur car is really nice, I saw u on crowchild (i think) a while ago!

redline
05-25-2002, 10:33 PM
Look at the top end of the graph you posted. It clearly shows that the GSR head out flows the b16 head on the top end by a tiny bit. But this is air flow not HP in a given app. Air flow is a big factor in HP but it is how everything works together.

B18c5 head is not ported just polished to take out casting imperfections. The big difference in power compared to a b16 head is the valves and cams.


Most people going LSVTEC are doing so for cost so that is way b16 heads are chosen. the majority are are using first gen b16a1 heads with b18a or b20 blocks.

If cost was not object i would not do a any kind of hybrid vtec engine and use a JDM ITR engine sleeved to 84-85mm and that gets you to 2L and you get the torque and higher reving engine.

Which head is best? depands on how good the porter is and which head they favor. Any of the heads listed can make big power. It just depands on how far you want to take it.

And with a GSR head the manifold limits out of the box power at higher RPM. But again if you must factor in the skill of the porter and engine builder. The fastest all motor car uses a GSR head and stock manifold. Just something to think about! :thumbsup:

legendboy
05-26-2002, 12:22 AM
ok:)

Daddymax
05-26-2002, 02:15 PM
Thanks legend boy!

boi-alien
05-26-2002, 06:50 PM
Originally posted by Daddymax
Baron. I wouldn't go that route. Before I dropped my engine I was set on LS vtec.

I did hours upon hours of research. Talking to people in toronto how had that engine and everything.

First of all when you look at B18's and B20's they dont' rev like b16's or Gsr's. So the bottom end isn't really built for the high RPM's.

B18's and B20's Don't have the oil squirters for the pistons like the ITR and GSR's .

If you build it right the motor can be powerfull and semi safe. But in the end it's going to cost your TONS. I would say 5000- 6000 installed. IF you want it right that is.

You could cheap out but then it might blow in 2 months or it won't be much more powerful than a B16a.

max right? heheh sorry guy, i'm not baron tho, we both have similar nicknames :D i think i've seen your rex in and around the crowfoot area tho right? nice ride man.

what do u have in your car right now? i want to find someone that actually HAS a crvtec, i want to take a spin in one just to see if it's as good as some people boast it to be, you know?

i mean i've been in cars that have b16s, ZCs and GSR engines in them, i want to see which one is better for myself.. but unfortunately it seems that not many people are into building hybrid engines here in calgary at least.

legendboy
05-26-2002, 06:55 PM
Originally posted by crxboi

what do u have in your car right now? i want to find someone that actually HAS a crvtec, i want to take a spin in one just to see if it's as good as some people boast it to be, you know?

i mean i've been in cars that have b16s, ZCs and GSR engines in them, i want to see which one is better for myself.. but unfortunately it seems that not many people are into building hybrid engines here in calgary at least.

me too, me too:cool:

Honda Driver
10-06-2004, 03:40 PM
Originally posted by Daddymax
Baron. I wouldn't go that route. Before I dropped my engine I was set on LS vtec.

I did hours upon hours of research. Talking to people in toronto how had that engine and everything.

First of all when you look at B18's and B20's they dont' rev like b16's or Gsr's. So the bottom end isn't really built for the high RPM's.

B18's and B20's Don't have the oil squirters for the pistons like the ITR and GSR's .

If you build it right the motor can be powerfull and semi safe. But in the end it's going to cost your TONS. I would say 5000- 6000 installed. IF you want it right that is.

You could cheap out but then it might blow in 2 months or it won't be much more powerful than a B16a.


well im not sure who u have been talking too but i felt that i should clear up some stuff here,

first, rpms is not really an issue, the B18b relines at 6800rpm and the B20z redlines at 6700, with the rev limiter removed they will both safely rev past 7000, granted thats not the 8200rpm of the gsr but i belive that has more to do with the vtec valvetrain then the bottom end (which obviously a crvtec or lsvtec motor would have.)
remember they are tuned from the factory for low end power (cams, intake monifild, ecu), they dont rev that high because they make no power up there ...that can be changed (a lot just from the vtec conversion),

second, yes they dont have the oil squirters....part of the converstion is putting them in, they sell kits for it

third, yes it needs to be built right if u do a sucky job then yes ur motor could quite posibly blow up not matter waht one it is, but a B20 or B18b with a turbo will handle more boost more reliably then a Gsr or b16 motor ne day, mostly thanks to lower compression pistons, if ure really gonna go crazy then it would cost u a lot of money no matter what motor u have, with the B18b/20 u allready got low comp pistions, block guards are pretty cheap, get a nice set of rods, and that motor will last just a long as any Gsr or B16 motor

fourth. 5000-6000 for a decently built B20 turbo is pretty acurate id say...but how much would a built Gsr/B16 and a turbo cost? the answer is more, which one is the cheaper allternative?

buh_buh
10-06-2004, 03:44 PM
holy shiat!! This thread is over 2 years old!!

rage2
10-06-2004, 03:47 PM
Ahh, old threads. We've learned a lot over the last 2 years, since I've tuned crvtec NA and turbos that spin up to 8000rpms.

The bottom end has no problems at that speed.


Originally posted by redline
Talk with Alan at Auto-Zeal or nelson at tunerworks both have experence with these.
haha talk about oldschool! :rofl:

redline
10-06-2004, 04:16 PM
no shit....

8000rpm... no way!! 10k or bust!!! :drama:

legendboy
10-06-2004, 04:21 PM
haha i remember this thread. My big argument with redline :rofl:

btw i've been running an lsvtec with a b16 head and ls bottom end for a while now. seems to work pretty damn good together!