VTEC Exhaust Cam not opening

[DavidV]

so my NA build was tuned a few weeks ago. Making a dissapointing 175. Considering we were looking for something closer to 230 whp, something is definitely wrong. Im pretty sure the VTEC on the exhaust cam isnt opening up. The problem first occurred before the engine was ever in the car. When we were trying to time the cams with it out of the engine, we had the same problem. The mechanic said it was probably because of air leaks and should be good once everything was hooked up. Well, he was mistakingly wrong. Does anyone know what could cause vtec on the exhaust cam not to open up? Ive just been driving it around with the 175 whp because i need the car for school. I want see if there is anything I can try before we have to go take the head off.

[yellow ek]

Elaborate a little more on the problem you had when timing the motor out of the car, what is done to the motor and what kind of dyno did you have it on. If the graph in your sig is from the 175 pull, it looks pretty good. If the exaust cam wasn't opening it should fall off up top.

[punkr6]

so my NA build was tuned a few weeks ago. Making a dissapointing 175. Considering we were looking for something closer to 230 whp, something is definitely wrong. Im pretty sure the VTEC on the exhaust cam isnt opening up. The problem first occurred before the engine was ever in the car. When we were trying to time the cams with it out of the engine, we had the same problem. The mechanic said it was probably because of air leaks and should be good once everything was hooked up. Well, he was mistakingly wrong. Does anyone know what could cause vtec on the exhaust cam not to open up? Ive just been driving it around with the 175 whp because i need the car for school. I want see if there is anything I can try before we have to go take the head off.

you make me wanna punch a baby, re write your post and read it before you hit submit...

[DavidV]

Let me restart

My car was tuned at Balanced Performance by Ed on a dyno. The result was a weak 175 whp. We were looking for something more like 230. The cams in the car are crower stage 2 with the bigger lobes. (They might be called stage 2.5 because of the bigger lobes idk). It was being tuned on a p72 hondata s300 ecu.

We think the problem is that the VTEC on the exhaust cam is not engaging. The VTEC on the Intake cam is engaging though. We know that some sort of VTEC is engaging because it does give about a 10 hp boost and gets louder when vtec should hit.

When the ENGINE was out of the car and on a stand, we were timing the cams with a tool from honda that simulates oil pressure by using air pressure. The engine was not on a dyno out of the car. Only the vtec on the intake came was engaging when the engine out of the car. The mechanic said that it was most likely due to a leak and would be fine once the engine is in the car and everything is hooked up.

The dyno chart in my sig is not the actual dyno. It is just some picture of a dyno. The horsepower does start dropping off around 6.5-6.8k. With the crower cams, horsepower should be able keep increasing over 7.5K at least.

let me know if this still wants you to kill a baby .
Also left me know if you need any other information.

[punkr6]

what engine ?

[DavidV]

h22

[yellow ek]

What all is done to the motor for your "N.A. buld". We know cams, but what else did you do, rods, pistons, pnp, valves, intake manifold, header, etc.
I have heard that the rod that goes through the rocker arm can be turned backwards. I have not run into this personally, but knew a guy that said that this was a problem on his motor.

[DavidV]

1997 prelude project
if that doesnt work try this
http://www.preludeonline.com/f82/my-...roject-242375/

[yellow ek]

Looks like a great build. I am going to look at a spare h22 head I have tomorrow to see if I can come up with any other ideas. It may be something simple that didn't get put back in the head during assembly, such as an o ring or an oil orifice.

[DavidV]

yeah thats what we were thinking. Im probably just going to have to take off the head and give it a look.

[Black4DrEK]

Ever got the head checked out by a shop?

[slimjim]

got spare h22 head complete for 125 text 423-339-7048

[BABY J]

That graph (in ur sig) doesn't show a VTEC crossover anywhere --- at least from what I can see.

[DavidV]

The graph in my sig is the graph to that engine.
I still dont have it fixed yet because I need to car for school. But whenever i have time I will be taking it up to the shop to try and fix it.

[ls-r teg]

check oil pressure

[Vteckidd]

H22 are notorious for having dents i the oil pan effect VTEC engagement although it should be on both sides, not just the exhaust.

I would remove the valve cover and cams first, and put air pressure to the rails and see if all the pins lock in vtec. If they do not, you have an oil pressure distribution problem.

[DavidV]

It has a brand new moroso oil pan, so i dont think that would be the problem. but when we open it up, I will make sure to check that.

[DavidV]

I have another theory as to what could be wrong.

The Lost Motion Assembly's could possibly be bad. I think like '97 or '98 and earlier had hydraulic LMS's. Honda changed them to a spring type because of failures with the hydraulic ones. Since my head is from a '94, it would have the hydraulic ones in it.

You can hear when LMS's are going bad because they create a slight knocking noise at certain rpm's. We did find a knocking noise at about 1600-1800 rpms similar to ones we have heard in videos. So we are going to talk it over with the mechanic first before we go buy some new ones and swich them out.

Here is a Link that explains in much more detail about the LMS's. And a how to on switching them out.

http://www.honda-tech.com/showthread.php?t=2564272

You can start hearing it at 3 seconds, gets louder at 6 seconds, and when the rpm's drop you can hear it one last time kind of loud.

[Vteckidd]

LMA dont effect VTEC engagement, they will effect your cam wear though. They are cheap so i would just go ahead an change them out anyway if you go in there

[DavidV]

If one or more of the LMA's were bad, the Vtec lobe would not sit right and possibly keep the pins from locking in. Am i right? Couldnt this affect Vtec? I know that Vtec IS engagine, its just weak.

[DavidV]

The engine was opened up yesterday and we replaced the LMA's. Everything inside the engine looked fine and nothing was missing or broken. My VTEC is still weak and i was another theory. I have read other people having weak vtec problems and it being their distributor. The head in my car is from a '94 and the distributor is from a '99. Does anyone know if a distributor from a '99 head will work on a '94 head?