Thread: Need some valve train help.

Update:
Uninstalled the stock cam, removed the HLA, rebled it, blew the head's oil port with compressed air and reinstalled the S3 exhaust cam. Same shit, 25 psi in #4. So much for my theory. I'm at a loss.

Only other test is to put that same cam in another engine. Maybe send it to someone for them to try out or if you know someone nearby. If it does the same in another motor there is something wrong with the cam....More than likely bent.

You are talking about something that all it takes is .010", a hundredth of an inch of it being bent to cause the issue your having.

The de normally has a set non operating lash that is set by shims, usually somewhere around .007 on the intake and .009-.011 on the exhaust to allow for heat expansion of the exhaust valves. The specs are in the FSM. All it takes is slight bend to do what its doing.

Only other option is to try it in another motor. If it doesnt do the same thing in the other motor then there is something wrong with your motor, either valve seats are worn that has closed the lash, highly worn cam journals or something.

Kyle is 13 miles down the street, but that would be asking a lot.
@Kyle

Eh, takes less than 30 minutes to swap out a cam. Again its the only other logical option.

I don't really care. If you have a shelter that we can install the S3 back into my car, I do not mind using my car as a guinea pig. I got cams out the wazoo for a DE.

The car is my daily driver, I do not have other options right now so it can be done on a Saturday, Hank, if that is ok?

EDIT: This Saturday coming up, 12/15, I will be busy in the AM and early PM.

Thanks Kyle. I don't think I have anything going on for Sat. Yes, I have a heated garage we can use. Let me find out from the boss what things look like for Sat. and I'll get back to you tommorrow some time.

Update:

Just to get closure on the issue, I sent the cam to JWT for inspection. This is what they found:

Hi Hank,
We received your ECU and used JWT S3 exhaust camshaft today (Tues Jan 29th). Our shop checked out the used cam and found it is bent .004" and the #4 cylinder would be effected by this which is what you found. Our shop found a loose JWT S3 exhaust cam by itself and said we can sell it to you (this is a new cam) for a special price of $100.00. Let me know if you are interested and I can add that to the order. Also let me know if you want the bent cam returned or we discard it for you. Our lab still has to upgrade the ECU which they can get done soon once you advise me on the cams.
Best Regards,
Ben Pila
Technical and Sales Support
Jim Wolf Technology, Inc
212 Millar Ave
El Cajon, CA 92020
(619) 442-0680 Mon-Fri 8am-5pm Pacific Time Zone
(619) 579-8160 24 hour fax
JIM WOLF TECHNOLOGY, INC. / NISSAN PERFORMANCE / NISSAN RACING /INFINITI PERFORMANCE

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On 1/6/2013 8:04 AM, Henry Lint wrote:

To whom it may concern,

I recently purchased a set of used JWT SR20 S3 cams. After installing them, I discovered the compression in the #4 cylinder was @30psi. 1-3 were all at around 160psi. After doing a leak down with compressed air, I determined air is leaking out the #4 exhaust valves while the #4 piston is going through it's compression stroke, hence the low compression. I check all of the other valve train components for that cylinder and they checked out okay. I even went so far as to swap the hydraulic lash adjuster from the #1 cylinder to the #4 cylinder, only to have the same result. I then proceeded to put the stock cam back in and compression came back up to normal. With all of that being done, I've come to the conclusion that there is something wrong with this S3 exhaust cam. The baffling part of it is there is no sign of damage, bending, excessive scoring, etc. The cam installs in the journals just fine and spins freely.

I'm writing to you to see if you've seen this sort of thing before and if you have any insight as to what the issue may be. I'm willing to ship the cam to you if you need to look it over and see if it's still within spec. I would really appreciate any help you can provide to resolve the issue. I've heard nothing but good things about your products and customer service. Again, any help you can provide would be appreciated. Thanks.

Hank Lint
(hammerin hank on SR20-Forum)
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Amazing!

awesome deal...did you get the other cam for 100 bucks??