[A_U_Tai_Mai_Shu]

to any of you ls/vtec or crv/vtec members, what is your redlines? I here some are like 9k

 

[Fentoozler45]

9k is going to be too high if you are looking for reliability. The rod ratio of the b18b1 doesn't change with the addition of VTEC. LS/VTEC redline is going to be limited to around 8k due to the low rod ratio. I can't recall the rod ratio for the b20, but I believe (don't quote me on this until it is confirmed) that the b20/VTEC is similar in this regard.

If you are looking to rev high with an LS/VTEC, you can increase your rod ratio in one of two ways....

1. Find a b17 crank and use it instead of the b18b1 crank. b17's are rare, so you may have trouble finding a b17 crank. Also you will lose some displacement with this method.

2. Add deck height. This method is much more expensive, but you wouldn't lose displacement like you would with the b17 crank.

I won't get into any specifics right now because it's 2am and I'm at work. I know that MD has made some excellent posts on this subject in the past, sadly some of them are lost since they were from the old forums.

Hope that helps and as always, please correct me if I have given any misinformation.

 

[A_U_Tai_Mai_Shu]

thanks for the info but what i wanna know is if anybody with a ls,crv/vtec what are there redlines cause i know not all are the same seeing that most and all are custom made.

 

[JustinKlemgold]

Just curious, why do you want to know what the redline is? There is much more to performance than a high redline. You can rev that high all day long, but if you're not making power all the way to 9K you are wasting your time...

 

[A_U_Tai_Mai_Shu]

good point but i would like to because on that mtv street racing thing( i know it's already old but this came up over lunch) he was revving to 5k to start and redline was at 9 so was there not much power in the other 4 k?

 

[JustinKlemgold]

Nobody said that. The point I am trying to say is...well let's take the GSR for example. It's redline is 8100. A lot of people will ask, "How can I increase my redline?" And people like MD will reply that there is much more than increasing your redline. He'll state how to do it, then he'll tell you that unless you do this and this, it will be pointless to have the redline that high because you are out of your powerband and all that time up in (say 8500 RPM) is just a waste because your torque curve is falling rapidly...understand?

Now I'm sure that on that show, that kid had lots of other performance mods to his engine that made revving that high practical and useful. If you're just trying to raise your redline but have no idea why (Just doing it to say 'hey guys, I have a 9K redline) then you are going down the wrong path. There is much more to an engines performance than how high the redline is. You have to make power ALL THE WAY up to that redline...

 

[A_U_Tai_Mai_Shu]

ok so i should ask to see some dynos to see where the top hp and stuff is

 

[MichaelDelaney]

all the B20VTEC's I've seen that make 240-245 whp and 150-160 ft lb torque only have a 8000 rpm redline...they have displacement and torque,....they don't need to rev high to make hp and their rod ratio is not helping your cause on a daily driver.

 

[SpoonVtec]

mine is at 10000 but i never have taken it that far. even tho my motor is built. until i get an stick tranny i would not try it, but yes lsvtec safe is around 85 to 90.

 

[A_U_Tai_Mai_Shu]

Are all EDit= vtec heads the same cause i have a grs and delsol vtec head (is this the same as a b16 ?) witch head will give more hp or will that come from the part of it is put together. Should this be another topic?

 

[MichaelDelaney]

Are all vtech heads the same cause i have a grs and delsol vtec head (is this the same as a b16 ?) witch head will give more hp or will that come from the part of it is put together. Should this be another topic?

GSR head intake port has a straighter shot angle into the combustion chamber than the Del Sol head. Stock wise, the GSR port volume is larger. Yes the 1994 and newer Del Sol engine was the B16A. Before 1994, the Del Sol had the D16Z6 SOHC VTEC head. Port the B16A head and it will be the better of the 2. If you don't plan to port then, the GSR is the better of the 2 for an LSVTEC's rod ratio and powerband location needs. And if you spell VTEC like that again, I'll stop answering any more questions from you and consider you prime a candidate for promotion to become Uncle Ben's newest nephew.

 

[A_U_Tai_Mai_Shu]

where is the typo

 

[Fentoozler45]

VTECH =

VTEC = Variable Valve Timing and Lift Electronic Control

Saying your Honda/Acura has VTECH will get you more noogies and titty twisters than you can stand.

 

[MichaelDelaney]

here are some "average" b20vtec dynos. they make good power up to 8000 rpm...you don't see them gaining much more above that...it either levels off or decreases

it really depends on the crank, CR, cams and injector sizing you use if you want to see gains above 8000 rpm...
like this one that has 12.1 CR and Jun 3 cams...

so there is no real need to gamble with more than an 8k redline using the stock CRV crank.

 

[spiff]

i have an ls v-tec and my red line is at 8k compared to my 6900k stock

 

[20lb.teg]

http://www.imagestation.com/picture/sraid28/p3a33e792b2de846c3229948fc6272707/fd6b8680.jpg[/img]]
VTEC = Variable Valve Timing and Lift Electronic Control

Saying your Honda/Acura has VTECH will get you more noogies and titty twisters than you can stand.

Well, VTEC actually stands for Variable Valve Timing Lift and Electronic Control (switch your Timing and your And) and then it would be perfect, but hey, who's being nitpicky...

I'm just messing with yah, just wanted to lighten up the situation a little.

Later,

Sean C.

 

[Ghostgsr]

Does anybody know if there is a difference performance/power wise between using an itr head compared to a gsr head for an ls/vtec conversion? Also, I take it when you do the conversrion that your redline will increase from 6900 to around 8000? Thanks.

 

[MichaelDelaney]

the problem with power comparisons on different dynos on different cars is that they have different tuning , IM, cams, pistons, and exhaust system packages.

the best true comparison to tell what the differences are only due to the heads would involve taking a car, using the same cams, IM, block, and exhaust system and dynoing with each head separately. Each engine package would then be tuned to their optimal performance.

that would then tell you which head is truly better.

unfortunately no-one will have that comparison for obvious reasons.

you will be getting people posting up B20VTEC dyno's with the different heads and saying one is better than the other based on these.

be careful as to how you interprete what they tell you. take it with a huge grain of salt.

In basic terms, unported, the heads are pretty close and the B18C1 may actually flow better since the stock port volumes will be bigger since the stock head was meant for a 1.8L and not a 1.6L. The stock (unported) b16a head port volumes may be too small for a 2L.

A stock ITR head (which is a b16a head ported by the factory for a 1.8L) would outflow the GSR head in the upper rpms above 6000 rpm. As was stated in this thread found in the COMMoN TOPICS, the stock ITR head has 60% less flow drag than the stock GSR head and will provide better flow quality.

 

[Louse76]

While we're on this subject... what would be a safe redline for my future setup? I understand that reving past its optimal powerband is pointless, but I'm mainly concerned with misshifting etc.

B18B1
Dual Valve Springs
Titanium Retainers
Stock Valves
Two Layer Head Gasket
PR3 Si Pistons
Crower 404 Cams

(Some of that may have nothing to do with effecting redline, but I'd like to be complete).

Thanks.

 

[MichaelDelaney]

that's not an LSVTEC or B20VTEC Louse...so it really isn't an appropriate extension of this thread: you're mixing apples and oranges...

However since you brought it up, your package is a straight LS. Your rod ratio is the same as these.
Those Crower nonVTEC cams however don't make any more power after your stock LS redline, whereas the VTEC cams start making power at around 6000 rpm and go up to 8100 rpm minimum for the stock VTEC cams. So there's no reason to extend the 62404 redline up to 8000 rpm like the LS VTEC or B20 VTEC.