[JLyons]

I am having trouble with my engine running a little rough. I have the MAF pretty much dialed in as well as the injectors. They are good enough for now. The problem I am having is the ACT is way high it seems. Around 190-220 at part throttle. Is this normal for an NA engine? ECT stays around 180. I used EA to get an idea for injector timing. My Cam is 242/248@.50 .600 Lift L/C 110. Anyone know what might be the problem? Attached is my recent datalog. Thanks for any help

Josh

[decipha]

where is the act mounted?

[JLyons]

It's located on the intake on the #4 runner fairly close to the throttle body.

[Vortech347]

Is it a metal or plastic ACT sensor? The reason I ask is you maybe getting some sort of heat soak?

I had much cleaner ACT readings when I started using one that was plastic.

That seems really high, I don't hit 220 ACT's even with my blown car unless I'm hot lapping around the road race track. Crusing with the Vortech I'm around 150-160.

[JLyons]

It is the white plastic kind. I bought the Mass-Flo EFI kit for my cleveland. Of course I put new heads and new intake on their that differs from the kit but I drilled a hole for the ACT in the same spot as the kit.

[tremec77]

Where do you live? WHat are the air temps like there? I'm guessing you have a bad sensor or your cooling system isn't working properly causing your intake to become heat soaked. Do the temps go down when you are driving? They should go down when you are cruising but come back up when the throttle is closed at idle.

[EDS50]

62# injectors with a 30# cal'd maf? Post your tune, with ect's in the 180s your cooling system is functioning fine. Your act's are way off for your combination unless your in death valley or Nevada. If the act sensor was bad it would normally default to a value off the top of my head around 160 degrees or so but dont quote me on it. I think you may be getting false act readings based on your maf curve/injector settings. I wouldnt see acts that high with a blower in 95 degree heat and 100% humidity in Florida. The engine running rough is indicative that more than likely your maf curve is not as dialed in as you think.

[JLyons]

Live in Florida but it has been in the 50's. Have not been able to drive it yet buy I stick a big fan out front. Cooling system stays around 180. I'll check the sensor. Hopefully it is faulty and that's it. I recently reset my valve lash because I was hearing chatter. If I did this wrong would that be the cause of the high temps in the intake?

I'll post my tune when I get home tonight. Hopefully I did not botch it to bad.

[EDS50]

Live in Florida but it has been in the 50's. Have not been able to drive it yet buy I stick a big fan out front. Cooling system stays around 180. I'll check the sensor. Hopefully it is faulty and that's it. I recently reset my valve lash because I was hearing chatter. If I did this wrong would that be the cause of the high temps in the intake?

I'll post my tune when I get home tonight. Hopefully I did not botch it to bad.

When doing the valve adjustment, how much did you tighten the lock from 0 lash? Which method did you use to do the valve adjustment?

[JLyons]

There were a few different ways to do it but the way I did it was:

For intake-On num 1 cylinder I waited until the exaust lifter started to come up then found 0 lash and turn 1/4 turn. Then followed firing order.
For exhaust - On num 1 cylinder I waited until intake lifter was at max lift then adjusted exhaust litter 1/8 past 0 lash. Reason on different settings was the exhaust was opening to much and I couldn't get good compresssion.

Hopefully that is right. Is there a more accurate way. My cam is fairly agressive too with 1.7 rockers.

[tremec77]

I guess I should have clarified what I meant by a bad sensor. I have had an IAT sensor read high do to oil on the sensor. It didn't trip a code and it still varied its range, it just didn't vary by more than 5-10 degrees. I'm guessing it was because the oil on the sensor was insulating it.

The way you did your valve adjustment is correct.

[JLyons]

If my intake valves are not closing completely could that cause high temps? Not sure if they are closing for sure just a guess.

[tremec77]

If my intake valves are not closing completely could that cause high temps? Not sure if they are closing for sure just a guess.

Yes, but if you did the adjustment like you said, then thier shouldn't be any reason for the intake valves to be stuck open. One way to tell is to pull the valve covers and rotate the engine to TDC and see. You should be able to "wiggle" the rockers when the valves are closed. I'm guessing you installed the correct springs with the cam???

[EDS50]

If my intake valves are not closing completely could that cause high temps? Not sure if they are closing for sure just a guess.

I know on my trackheat heads once zero lash is found I turn mine 3/4 of a turn before locking it down. I found 1/2 was a lil noisy os 3/4 was good for me. I would recommend at leat half a turn before you lock em down. You also need to ensure your lifters arent collapsing while you are adjusting the lash through the other cylinders in the firing order which would gove you a false lash adjustment.

[JLyons]

Ya while I was adjusting them I was priming the oil to pump oil into the lifters so they wouldn't collapse. 1/2 was too much for me because my intake was way open I couldn't get any compression. Maybe 1/4 is too much as well. I could try 1/8 turn on both intake and exhaust.

[EDS50]

Ya while I was adjusting them I was priming the oil to pump oil into the lifters so they wouldn't collapse. 1/2 was too much for me because my intake was way open I couldn't get any compression. Maybe 1/4 is too much as well. I could try 1/8 turn on both intake and exhaust.

I would try a different valve adjusting method. 1/2 turn should not be too much. Also if your lifters are bleeding down that fast its time for new ones.

[tremec77]

Ya while I was adjusting them I was priming the oil to pump oil into the lifters so they wouldn't collapse. 1/2 was too much for me because my intake was way open I couldn't get any compression. Maybe 1/4 is too much as well. I could try 1/8 turn on both intake and exhaust.

There is no reason you can't run 1/2 turn. You don't want your lifters rock hard during adjustment anyway. The whole point to preloading the lifters is to have them slightly collapsed when the valves are fully closed. Do you have the correct push rods?

[JLyons]

I'm fairly certain I do. I used a pushrod checker to find the right length. What would be the best method to calculate the right size?

[85GT]

Did you degree the cam? What's the intake centerline?

You have 20 degrees of overlap. If the cam is too far advanced, you're probably blowing a bit of exhaust up into the intake.

[tremec77]

I'm fairly certain I do. I used a pushrod checker to find the right length. What would be the best method to calculate the right size?

You need to use your checker and find the length that shows the thinnest wear pattern on the valve stem.

[EDS50]

I'm fairly certain I do. I used a pushrod checker to find the right length. What would be the best method to calculate the right size?

You need to use your checker and find the length that shows the thinnest wear pattern on the valve stem.

And also promotes proper rocker movement, alignment and geometry.

[351C4vEEC]

I realize your combo is a lot more radical than mine but, I'd love to see your original tune on your Mass-flo 351C based motor. It might give me ideas on how to go with mine. Thanks Mike

[JLyons]

I realize your combo is a lot more radical than mine but, I'd love to see your original tune on your Mass-flo 351C based motor. It might give me ideas on how to go with mine. Thanks Mike

Unfortuntely the tune was on a chip I pulled off the computer that came with the kit so I do not have it. I am pretty sure they had it fairly stock with just the injectors and MAF in the tune. Reason I think that is because I had to run the car for awhile for the car to "learn" to behave so my guess is they just threw those numbers in and enabled CL and adaptive.

[JLyons]

I'm fairly certain I do. I used a pushrod checker to find the right length. What would be the best method to calculate the right size?

You need to use your checker and find the length that shows the thinnest wear pattern on the valve stem.

And also promotes proper rocker movement, alignment and geometry.

By thinnest, do you mean what promotes the least amount of movent along the valve stem?

[JLyons]

If my intake valves are not closing completely could that cause high temps? Not sure if they are closing for sure just a guess.

Yes, but if you did the adjustment like you said, then thier shouldn't be any reason for the intake valves to be stuck open. One way to tell is to pull the valve covers and rotate the engine to TDC and see. You should be able to "wiggle" the rockers when the valves are closed. I'm guessing you installed the correct springs with the cam???

Yes the heads came assembled and ready for the cam. I bought everything from the same company. They suggested the cam cut based off what I wanted. I really hope I didn't screw myself by not doing the research myself on the cam I would need.

[JLyons]

62# injectors with a 30# cal'd maf? Post your tune, with ect's in the 180s your cooling system is functioning fine. Your act's are way off for your combination unless your in death valley or Nevada. If the act sensor was bad it would normally default to a value off the top of my head around 160 degrees or so but dont quote me on it. I think you may be getting false act readings based on your maf curve/injector settings. I wouldnt see acts that high with a blower in 95 degree heat and 100% humidity in Florida. The engine running rough is indicative that more than likely your maf curve is not as dialed in as you think.

Here is the tune I used for that datalog. Today I tried from scratch with stock 30# MAF. With 408 CID, 60# injector offset with 62# on injector high and low. Also put in injector timing in the ballpark of what I needed based off of EA. I ran the car and of course it was super lean as expected, but the ACT's were reasonable and stayed around 140-160. I then corrected the MAF and ran the car again with LAMBDA around .95 and my ACT temps shot up to 200. So I am at a loss.

[Vortech347]

Have you thought about relocating the sensor to the intake tract? Like before the Throttle Body?

Where is your filter getting air from?

[JLyons]

It is getting air from the old style air cleaner. Basically the setup is air cleaner on top of maf on top of throttle body on top of the intake. The maf basically sits in side of the air cleaner on top of the throttlebody.

[tremec77]

I still think its your sensor. Go to the autoparts store and pick one up. If it doesn't help, return it. According to the Ford Manual, the sensors can vary about 15% from one to the other. So with that in mind, 200 isn't that outragious when you are already seeing 170. I do agree that 200 isn't typical though. I agree that you may want to try relocating the sensor too. Maybe into the breather. Most of us here are used to seeing ACTs in the 140 range because we are using the usual MAF setup or we are running a cold air system where you are using a "carb" setup. Heat rises.

I'm not sure where Ed was going when he said it might be because you are changing your MAF settings. Maybe he can explain this to us. I thought the reading you see in the datalogs are just the actual readings from the sensor. Maybe the EEC does some calculating that I'm not familiar with.

[JLyons]

I'll pick one up and give it a shot. Also, I read that a cam with an overlap like mine is geared for racing and higher rpm. Does that sound right? Should my idle be higher than 1000 rpm? I am trying to solve a few problems at once so that's why I have a ton of question. Once I get this act thing situated ill put up another post for the other problems.