Radical idea : Can we use i-VTEC cam gears? - Honda Prelude Forum

Artifex · 01-15-2003, 07:20 PM

This is a question for all the other wrencheads. If all you know about is bodykits, this is not the thread for you.

After reading about how the i-VTEC system works (http://asia.vtec.net/article/ivtec/index.html), I came to the conclusion that VTC is a kick ass idea. Having both VTEC and VTC makes for killer head flow, and the performance of the RSX-S pretty much bears that out (man, I am so jealous of the K-series now).

The one thing that struck me about VTC is that pretty much all of its function focuses on the cam gear/sprocket. Cam gears are (relatively) simple, and the question immediately raised in my head : Can we remove the cam and sprocket from a K-series with VTC and use them on an H22?

The only obstacles I see are the following:[list=1][*]Sprocket outer circumfrence. Any differences between the H22 cam gear circumfrence and the K-series will destroy the head because timing will be way off.[*]Diameter and dimension of the cam splines. Will the K-series gear fit over the splines of an H22 cam?[*]Actuation. The article mentions that the sprocket is hydraulically actuated. What else is necessary if the sprocket is transplanted?[/list=1]

With enough luck and ingenuity, this may be a doable job. I can even conceive of machining some custom sprockets should certain dimensions be off.

I think this idea is worth pursuing, becuase coupled with aftermarket cams, there is a large gain waiting. Aftermarket cams have huge tradeoffs in power density over the RPM range; tradeoffs that would no longer be necessary with VTC cam gears. I am thinking like 150 ft/lbs of torque all the way through redline....

I anticipate that the next question will be : how would you control them if you could install them? I am electronics guy, that is my bag. If someone can install the cams, I will come up with a way to control and tune them.

NoRice4U · 01-15-2003, 08:00 PM

there is a reason why aftermarket companies exist

hahah

silver5g · 01-30-2010, 11:25 AM

Bump.. I had been thinking about this when I posted a thread about putting a K20 head on an H22 but everyone decided to flame the idea off as useless. This was before I fully understood the cam gears are the main importance in VTC. I think the only way you could do it is if you used a K series ECU (KPRO is probably the only option).. It really, really is not THAT unfeasible to convert the H series to a sprocket timing drive, this is what machine shops are for. I can't help but think the H22 would be a monster because it could still rev almost to 8k (maybe more I haven't been around the Prelude scene for years I'm forgetting details).. this would be extremely desirable because the current K series big displacement K24 is limited mainly by it's inability to rev past 7kish.. I think this idea is more than worth pursuing, it could be what it takes for the 5th gen to compete with RSX-S in a straight line and all around have a more smooth powerband...

-Current RSX-S owner and previous 5th gen owner.

tom27897 · 01-30-2010, 01:41 PM

subscribed*

I definitely wanna see how this ends up. Sorry i can't shed some light on the subject tho

free bump

Artifex · 01-30-2010, 04:21 PM

LOL, guys this idea is DOA. You need oil where the cam gears are, which isn't happening on an H22.

pIERCE · 01-30-2010, 04:42 PM

Yeah, stop being a newb, Ken.

2000h22a · 01-30-2010, 04:47 PM

way to bump a 7+ year old thread

bouckarooo · 01-30-2010, 10:08 PM

whoa whoa whoa whoa.....

import tuner and brian crower got together and place and ivtec k20 typ r head onto an f22c. it was unreal. It may not seem possible but you never know.

Honda Cam Tuning - Performance Upgrade - Import Tuner Magazine

red92si · 01-30-2010, 11:44 PM

F22C uses a timing chain instead of a timing belt making the addition of the requisite oil into the system less of an issue.

I don't think think you'll see this happening with an H22 unless you fabbed the engine to the point where you might as well have put that money into building it conventionally.

SH DRIVER · 02-11-2010, 05:48 PM

ivtec works using a feed back type system.
The ecu controls the valve timing thru hydraulic pressure and has a sensor that reports back to the ecu how much the valve timing has been advanced or retarded. The H22a4 engines ecu has no valve timing inputs or outputs so for all practical purposes this idea is a non starter. Keep in mind though that the H22a4 engine has a variable cam overlap timing system . The H22a4 engines variable cam overlap system is just a 2 step system where the k series engine is continuous in its application.Because the H22a4 engine has a lower VTEC change over rpm then any other performance originated Honda engines , its valve overlap at mid rpms is probably pretty decent . And because its engine red lines at 7400 rpm as apposed to as much as 9000 rpm on a S2000 and 8000 rpm on the RSX for example the advantage of greatly increasing valve overlap to obtain higher Hp is not as great as engines with higher rev limits I would guess.Of coarse any engine with continuous valve timing reaps a significant benefit with respect to improved rpm fuel economy and lower emissions do to the ivtecs ability to drop the over lap all the way to zero at low rpms.

red92si · 02-11-2010, 06:18 PM

Thanks for the lesson

That info is provided via link in the first post.