Dai_Ca_Vietnam_H22a4

About a few weeks ago, I decided to upgrade my camshafts from JDM Type-S camshafts to Skunk2 stage 2 pro series camshafts. This event followed by me dropping my car at the shop. Later on in that week, I received the most devastating news from my mechanic. All my rocker arms were literally eaten way. As for my Type-S camshafts, I had them in my car for exactly 19,547miles. The lobes were totally eaten away. They look like a set of camshafts that has been in a car for 200,000 miles. I could not make out the problem at first, so I did a little research on my own on Honda-Tech. I learned that on the original Prelude Type-S head, the valve guides sits lower to allow for clearance. I made a painful mistake and overlook this problem. I just want to state this information to prevent any other HT member from making the same mistake I did. No wonder when I put my car on the dyno, I only made 186.6whp. I had RMF header, PYR ported head, and completed valve train. My specs are in my Biography page.


Modified by Dai_Ca_Vietnam_H22a4 at 8:58 PM 6/25/2006


Modified by Dai_Ca_Vietnam_H22a4 at 6:54 PM 6/27/2006

98vtec

u mean do not install PRO2 cams in an unmodified valve guide head.........

Dai_Ca_Vietnam_H22a4

Hello man, I have spoken to you before. I think those lobes on the Type-S cam are over size that is why the valve guide sits lower on real prelude type-s head. I just trying to trouble shoot the problem. Any suggestion would be helpful.

Dai_Ca_Vietnam_H22a4

I wished I had measured the lobes with a micrometer caliper before I installed them to compare them with Skunk2 stage 2 pros.

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dai_Ca_Vietnam_H22a4 &raquo;</TD></TR><TR><TD CLASS="quote">Hello man, I have spoken to you before. I think those lobes on the Type-S cam are over size that is why the valve guide sits lower on real prelude type-s head. I just trying to trouble shoot the problem. Any suggestion would be helpful.</TD></TR></TABLE>

the there is only one type S cam and its so mild that you should have no problem whatsover running that cam with even stock valvetrain.

i am very confused here........did you mess up your rocker arms by running the pro cams or the type s cams.

Dai_Ca_Vietnam_H22a4

I mess them up by using the Type-s camshafts.

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dai_Ca_Vietnam_H22a4 &raquo;</TD></TR><TR><TD CLASS="quote">I mess them up by using the Type-s camshafts.</TD></TR></TABLE>

i'm gonna call an install error. There's just flat out not enough lift on the type S cams to do that.

Dai_Ca_Vietnam_H22a4

Trust me 98vtec, I know they are mild cam when I purchased them. I just spoken to Pocketrocket Racing on HT, he claims he is an engine builder. Here is his quote,"installing high lift cams such as the factory Type S head or any brand, without changing the guides/retainer installed height means the retainers hits the valve seal/guide....a stock H22 head has the retainer hit the guide at 0.490 of lift..."

98vtec

and the type S lift is no where near .490"

Dai_Ca_Vietnam_H22a4

In your opinion why do you think the valve guides sits lower on the Type-S head. This problem is driving me crazy. What installation problem do you suggest 98vtec?

Dai_Ca_Vietnam_H22a4

I think he was talking about the valve guide clearance.

98vtec

its a different head designed for a different cam profile. Honda engineers didnt design the head for people to put high lift cams in there so they designed the valve guides in the type S head around the type S cam specs.

where did you find this info about the valve guides sitting lower, never heard of that before? I'd like to read it.

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dai_Ca_Vietnam_H22a4 &raquo;</TD></TR><TR><TD CLASS="quote">I think he was talking about the valve guide clearance.</TD></TR></TABLE>

and what makes the retainer travel....?


answer: the lift of the lobes.

Dai_Ca_Vietnam_H22a4

Here is the thread

https://honda-tech.com/zerothread?id=1081953

Dai_Ca_Vietnam_H22a4

True true. Please look at the thread<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">

and what makes the retainer travel....?


answer: the lift of the lobes.</TD></TR></TABLE>

98vtec

i understand what frank is saying......BUT what that doesnt explain is why most ( i say most because i cant say all because i dont know everyone, lol) these guys with stock valve guides who are running a much higher lift cam than that of the Type S cams, running non raised retainers and run into no problems with retainer to valve guide clearance.

this is some intersting stuff and is very intriguing to me.

Dai_Ca_Vietnam_H22a4

I am just as confused as you are about the same questions. There might be something technical about those Type-s camshafts. I read somewhere else about this but I just can't find the info now. The guy warned about the same thing. This same thing that they warned about happened to me. The question is will this happen again with my new set of Skunk2 pro camshafts. I will replace the rocker arms with a used set somewhere. I will keep this infomation posted. Thanks for your feedback 98vtec.

98vtec

if it happened with the Type S cams, it would be even worse with a higher profile cam, not to mention the Pro2's which are very close if not over .490" of lift.

hell the h24x cams im going to run have .500" of lift on the intake side and Rocket said that i wouldnt need any kind of modification to the head or anything else, that everything would be fine. After reading Franks opinions on that, im gonna send Rocket another email.

PirateMcFred

yeah, more lift means that more clearance must be made elsewhere. The Type-S springs, retainers, cams and valveguides are all different than USDM standard equipment (see link). Got any pics?

https://honda-tech.com/zerothread?id=1084868

This is the same issue when people try to run cams with .400" lift or more on H23s with stock valvetrain.

Pirate

98vtec

but Jdogg is still saying that there shouldnt be any problems with clearance so long as you dont miss a gear and go beyond the rev limiter.....something isn't right here.....

question.......what valvesprings where you running and what were you revving the motor out to?

edit:
Portflow dual springs
Portflow titanium retainers

i still wanna know what you are revving to.

PirateMcFred

Perhaps he's running his valve lash too tight. That increases lift at the valve and also messes with hot tolerances. It could be a lot of things, but I think that a simple inner spring and retainer upgrade installation should have eliminated any of these problems and would have been really cheap insurance. There is also the possibility that not all H22 heads were assembled exactly the same as eachother. If it was USDM parts on the tight side of clearance and then you throw some cams in that exceed those clearances then you will get damage.

Anyway it should be pretty common knowledge by now not to run them on stock valvetrain. What's cheaper, $150 in brand new inners and Ti retainers or $800 in new rockers alone?

Pirate

EDIT
Ok damn. I did not see that you had the Portflow valvetrain. hmm well that should definately not be a problem in terms of clearance. in that case it should not matter on the guides, the retainers will provide the necessary clearance. I han type-S cams for over 5000 miles and I have no issue at all reving to 7500+ with extended track lap work. I only have retainers and inners.

What about the rockers and lobes on the exhaust side? It should not be any issue over there.

98vtec

and which in his case he was using upgraded valvetrain.

i'd be interested in knowing the valve lash he was using.

dont upgraded valvetrain come with upgraded valvespring seats? I know that when i bought the IB spec valvetrain from Jeff, he sent me new seats. Never got to compare them to the stock stuff since i had to sell my head build. Maybe he was using the stock seats?

PirateMcFred

Edited above post...

The spring locators should not be an issue with Portflow VT. He should check the installed height of the S&R to make sure that he is running the proper seat pressure. Portflow know what their spec is. He should call them to double check.

Pirate

98vtec

pictures would be helpful

mgags7

i would really like to know how tight the valve lash was set, because there should not be any compatibility issue with parts, i believe this problem was installer error....

on a side note though, jd3jdm's rocker pads were pretty worn after only ~45,000 miles on the stock h22a cams, brad (rlz) made him replace them before he reassembled the motor because they were too worn (thanks jdogg)....