Stroker problem: fuel in intake runners, Wrong cam?

[tequila mike]

Am I on the right track here finally.
In over my head should be my middle name.
Built off Dinos formula site (low buck stroker)about a 2 years ago and has never run right. It always runs lean (aem wideband AFR meter) and over heats on the trail.
Plus high nox. Yesterday i replaced IAT Sensor and it was wet with gas???
I am wondering if i have a cam not suited for this build.
A few months ago i pulled the head to install The valve guide seals i had forgotten.
The intake runners were bleak with carbon deposits at least 5 inches in.
Did not occur to me at the time it might be a symptom.
Lost the records as to the exact cam i have in it.
What procedures should i use to determine the cam i need.
Am i on the right track with this?
Details
258 crank and rods
4.0 pistons
Quench height is 26ish i think.
Head gasket is .041
24 # injectors
New Fuel filter and regulator.
Every thing else is stock.
63mm throttle body
Cold air intake
ARF runs around 15.4 at idle and cruse.
goes to 12.7 w.o.t.
Am i on the right track with this?
Any help would be really appreciated.
What tests can I do to confirm hunch?
M

[SilverXJ]

The first step would be to determine what cam you have installed. I would also check to make sure it is ground correctly and installed correctly by degreeing it.

Your AFR numbers aren't too far off. 15.4: is a little lean, but won't hurt anything at idle. What does it run when cruising? 12.7:1 under WOT is fine if you aren't pinging. I am unfamiliar with your wideband unit, does it have some form of free air calibration?

Are you sure its fuel? There will be a little fuel and oil present in the intake manifold from the PCV and perhaps a bit of reversion. So, the intake won't stay 100% clean.

[tequila mike]

thanks for the reply
It is raw fuel on the iat I took out. It was wet.
Don't know how to determine which cam I have. Will research degreeing it.
The Bosch 4.2LSU sensor, which gives the controller its speed and accuracy, is laboratory calibrated at the factory and never requires free air calibration when used with an AEM Controller!
As to WOT I thought it should be down to 12.2 to 11.2
M

[SilverXJ]

12.5-13 for wot

[tequila mike]

This is from a tuners website
Tuner pros I think.
I am at 12.7 wot which is best lean. Would like to be richer at wot, closer to 11.8
AFR Lambda (λ)
14.7:1 1 Stochiometric
12.8:1 0.87 Lean Best Torque (LBT)
12.2:1 0.83 Mean Best Torque (MBT)
11.76:1 0.8 Rich Best Torque (RBT)
11.01:1 0.75 Flame speed fastest in cylinder

[SilverXJ]

It came from here: http://tunertools.com/articles/AFR-Tuning.asp. Which is just regurgitated from other authors, but without understanding or explaining the numbers.
See here: http://books.google.com/books?id=RYsglA ... 22&f=false

And here:
http://books.google.com/books?id=_MgGR7 ... 22&f=false More in relation to boosted and nitrous

There is no real number that is ideal for all situations. Unless you put the car on a dyno to find the best power at x afr at y rpm. 12.5-13 is an acceptable safe ratio provided there is no pinging.

With you magic number of 11.8:1 you are just throwing fuel out the tail pipe if you haven't put it on a dyno to see that it actually makes more power with that rich of an AFR.

[tequila mike]

Cool and thanks.
Please forgive my ignorance.
I was thinking about using regulated compressed air in one cylinder to determine if the valves were opening and closing at the wrong time based on the tdc mark.
Do you think this would give me any useful information?

[SilverXJ]

Please forgive my ignorance.

There is a lot of BS on the internet, you just need to corroborate it with other sources.

I was thinking about using regulated compressed air in one cylinder to determine if the valves were opening and closing at the wrong time based on the tdc mark.
Do you think this would give me any useful information?

I don't think that would give you much usable information. The balancer mark only gives you a few degrees, not enough to tell you when the valve starts to open. Not only that but you will have lifter bleed sown to contend with, which will skew the results.

A degree wheel and a dial indicator would be your best bet. But you need to know what cam you have

[CobraMarty]

Nice references.

[tequila mike]

Guess I might have to pull the cam.
Might be marked somewhere on it.
M

[cruiser54]

CompCams marks there's on the back.

[SilverXJ]

If you had a degree kit you could possibly degree it and try to match it to something

[tequila mike]

Thanks,That could save some labor.
Guess I will
degree it before I pull it.
I did use break in additive and recommended procedure.
Can you tell me some of the circumstances that would cause gas in the intake runners.
Ruptured fuel pressure regulator, vacuum and pressurized fuel through the vac. line.
To tall lifters causing valves to open to soon and close to late allowing some atomized fuel to be pushed in to intake during compression stroke,
Cam lobes allowing dwell past when the valves should be closed during compression.
Push rods to long similar to tall lifters.
Valves not closing all the way.
Weak valve springs??
Week lifters?
Low oil pressure to lifters?
???????????????????????????????????????????????

[SilverXJ]

Ruptured fuel pressure regulator, vacuum and pressurized fuel through the vac. line.

Yes, that is a very likely possibility

To tall lifters causing valves to open to soon and close to late allowing some atomized fuel to be pushed in to intake during compression stroke,

You should have backfiring though the intake and/or exhaust if the valves were being held open too long

Cam lobes allowing dwell past when the valves should be closed during compression.

Possibly, but that would have to be a very screwed up grind

Push rods to long similar to tall lifters.

Same as too tall lifters, valves held open

Weak valve springs??

Usually act as a rev limiter

Week lifters?

weak lifters or too short pushrods will cause lash, which would result in a noisy valve train.

Low oil pressure to lifters?

What is your oil pressure?

If the cam is advanced or retarted too far it could cause a problem like this. What does your torque curve feel like? Little to no torque at low RPMs, but a lot of power at WOT, or lots of torque at low RPMs and gutless at WOT?

Also, check your distributor indexing and cam sensor.

What else is it doing? You said it runs poor.

[tequila mike]

Thanks a lot for the indepth reply.
It doesn't run poorly, it does seem to be missing some low end torque.
Seems to stall (easier than when it was stock) going over obstacles on the trail.
I am getting some popping on high speed decel. A mechanic called it (lean popping)
No backfiring through intake or exhaust.
Oil pressure is up around 30 at idle and goes up to about 50 ish at speed,
Runs strong at wot, but seems to be, not really a struggle to get there, but just not a crisp curve. Seems to be missing some power.
Think I should go one tooth clockwise test drive than try one tooth counter clockwise and drive?
This is very perplexing.
M