Cam Timing

[SidWell]

Is there a quick or seat of the pants method to figure out if your cam timing is correct? I do not have a degree wheel or dial indicator. I have a new non-stock cam, new chain, upper and lower gears and tensioner. The notch aligns well using the first hole in the cam wheel, but, I am not sure that this is the best location as far as intake / exhaust timing goes. At this time, I just want to get the car running without stumbling and popping.

[HoustonZ]

I recently installed a turbo engine into my car and couldn't figure out why it was running so bad. Come to find out, the cam was retarded by a tooth. I just set the #1 piston at TDC and looked up the #1 intake and exhaust lobes. They should be pointing at 10 and 2 o'clock. The key is to notice if they are evenly out from straight up, 12 o'clock. Did that make sense?

[SidWell]

That sounds simple and makes sense. Thanks.

[PresaMax]

What kind of timing chain kit did you use? Just curious. I'm looking to replace mine. Thanks.

 

Julius

[SidWell]

What kind of timing chain kit did you use?

I got it from MSA in Orange. They are just down the street from me.

[Clifton]

Did it stumble and miss before the cam and was the cam the only thing done before the miss?

 

You can set the timing to stock but without degreeing it and having the cam card to go by, you could still be off 4*. Maybe more, maybe less.

[SidWell]

I am also in the process of installing a MegaSquirt and EDIS system. I have several issues going on at the same time. I am simply trying to get as many things as close as possible right now. If I can verify it is close, then I have one less issue to worry about while trying to get the car to run smooth.

[JMortensen]

The answer is no. You can check if the timing is close to stock, but aftermarket cams sometimes aren't ground with 0 degrees as 0 degrees. As Clifton said, they can be 4 degrees off by design, and they are sold with the assumption that the person installing it will time it and make sure it is degreed right. That's why you get a cam card with a new cam.

 

I expect your stumbling and popping is probably related to the EFI or EI and not the cam, but in order to do the cam right you have to take the time to do it right.

[Clifton]

I expect your stumbling and popping is probably related to the EFI or EI and not the cam, but in order to do the cam right you have to take the time to do it right.

 

I am thinking this too. I would put it in straight up for now if you can't degree it and look at the fuel for the stumble. You have a wideband?

[SidWell]

I was advised by a friend that I should get a variable cam timing gear and put it on a dyno. I am sure he is right but I cant do that right now. I am also chasing an issue where I cannot get the MS to advance the EDIS spark. I suspect that that is one of my biggest issues, but, I want to eliminate where possible. Yes I do have a wide band O2 sensor. I also have a 3 x 2 bbl fuel injection manifold. Yep, one butterfly per cylinder. That coupled with a ported and polished head and 6 into 1 equal length exhaust header. I welded the WB O2 sensor into the collector of the header. Not much is the same as stock except for the block. Since it is a street cruiser and not a full blown race car, I do not expect to wind it much over 6K rpm.

 

Who sells a variable cam timing gear for the L28?

[Clifton]

A cam, ported head. I think you'll want to rev it over 6k;-)

 

Kameari sells adj., around $200. I know you can buy the 8 hole one for less but they aren't easy to adj at a dyno. If it were me I would buy a mag base and dial indicater from HF (cheap) and set it to the cam card. I managed to get mine within 1* of what the card said. I wouldn't worry about the dyno until you get your AFR's set.

[Tony D]

Mag Base, Dial Indicator, and the Degree Wheel. Set it up as the Cam Cars says, THEN go to the dyno and try a degree at a time advanced and retarded to see where maximum performance occurs.

It 'may not' be as the cam card says. Then again it may.

 

But until it's 'degreed in', you will never know where you are...

 

If the engine won't advance and is getting it's trigger signal, I'd check settings and verify against another EDIS Box that it's correctly working. They are all over in the JY, and cheap, too!