360 build update

OK so we got the fuel sync set at 0 it does bounce to -2 back to 0 now and again...idk how much closer we can get it to stay at 0 then that. Second when the truck is idling the timing the scan tool read was 14* from what i've read around with these cams that sounds about right.

now these test were under no load sitting in park this is what im getting.

My buddy jay was bringing the the rpms up by 100rpms at a time with the scan tool to test it, once the truck hits 1400 RPMs the timing jumps up to 30* and it starts back firing. So we backed the rpms back down to idle at 750, now using the gas peddle we bring it up past 1400rpms it back fires a little once you hit 2400 rpms the computer brings the timing back down miss fires go away and as you continue to rev the engine up in rpms hitting 3,000RPMs the computer has the correct timing and you can just bury the tack to 6 grand no back fires nothing the truck just sounds great. Its just that first couple hundred rpms the computer is tricked for some reason thinking that the truck is running wide open.

The TPS sensor isn't tossing a code so I dont think its bad to make the computer think its going balls to the wall.

Im going to email Sean and see what he thinks.

I feel like we have taken a step in the right direction though in getting this thing dialed in though.

Any thoughts or help let me know guys.

the truck sounds so good at idle and once you get passed the 2400 mark omg look out the 3 inch pipes thing sounds mean!!!! shes just a little confused still.

Was also thinking about taking the tune out and seeing what happens.

Ok so I just herd back from Sean, guys fast with his emails lol, he said at 1400RPM that that 28* timing is right....now im scratching my head....

Just when I thought I figured the problem.

another quick update,

Sean is having me set the pre-load to half to 3/4 turn, thinks that the backfiring maybe do to a valve being open so gonna do what the man says. updates tomorrow!

need a running video with the exhaust done up.
sounds like your having as much fun as i did. i ended up with a bad cam and had to swap it out.

well I ran over today just to start the truck its -10 here with wind chill and while I was just warming it up i sat in the truck grabbing the wheel just thinking lol, and it came to me the backfiring isn't coming out the tail pipes, its trying to come out the intake....which means there must be a intake valve thats to tight and must just be barley cracked open....so if my buddy wants to today were going to undo all the rockers and set them at 3/4 turn and go from there.

also I didn't follow the rocker adjustment chart I just kept turning the crank till the cam let the lifters down off the lobe and went down the line setting the rockers...guess thats a no no lol. So all this ruckus may have just been my fault and not the computer acting up..


Update maybe later if my buddy wants to work on it...its freezing also ill take my video cam over there and get a running video.

Run your truck a couple minutes before you start the adjustment. You want to make sure your lifters are pumped up.

Yeah I will, how long you think two three minutes, I don't want the parts to be hot when I'm sticking my hands in there you know

here is where i was. hughes states that lifters should be 2 full turns and everybody else wants .035... or 3/4 turn. yes the old mopar flat tappets are 3/4 turn. just saying mine runs good and does NOT hang a valve out at .1 load 2 full turns. make sure you do the valve lash adjustments all at tdc per cylinder. or by the mopar valve adjustment chart.
PRINT
http://www.hughesengines.com/Upload/...alveAdjust.pdf

Yeah I know have two full turns but I should of started out at 3\4 and worked my way up, but yeah we didn't follow the chart so I'm almost positive thats where we went wrong.

let me ask?
who put the valve train on? you got the same one as i. do you remember about how the install difficulty was. rated from 1-5, five being the most cumbersome. how hard was that rocker system to install!
i cant wait to hear this answer!

I would give it a 2, my other buddy john did the lashing and torquing, but like I said he didn't follow the charts he just kept turning the crank until the lifters looked like they where off the cam lobe, he even looked at me at one point and said I think I saw the spring start to compress a tad, so tomorrow when its not negative outside lol, were going to reset all them.

If the lifters are pumped up it will compress the springs and open the valves. But they wil bleed down within half hour.

Installing them was pretty self explanatory, make sure the shaft is facing with the beveled side up, so that the screw sits down in it, lube the tips of the push rods, set the rockers down on it. Or at least thats what I did.

I mean what john did would that work or be ok, to just look at the lifters and watch for them to go on the round side of the cam and not on the lobe and tighten them down? Or is it absolutely mandatory to follow the pattern, bouncing from side to side when each piston is at TDC

ok so what I want to do is let all the lifters pump up by running the truck, then hurry up and take the pre-load off the rockers then start adjusting them going by the chart?

After running the truck try to get the preload off all the rockers fast so they don't bleed down. They will only bleed down under spring pressure.

Originally Posted by smity901

I would give it a 2, my other buddy john did the lashing and torquing, but like I said he didn't follow the charts he just kept turning the crank until the lifters looked like they where off the cam lobe, he even looked at me at one point and said I think I saw the spring start to compress a tad, so tomorrow when its not negative outside lol, were going to reset all them.

funny how easy it is when you just take your time. my speed shop dist and reinstalled these rockers. ONCE. f-ed them up pretty bad. i looked closely at them after i had the truck back and the mini shaft from one side to the other was out of level. on one stud the axes was higher than the other. they didnt pay attention to setting the mini shaft in the saddles, had one of the mini shaft up-side-down, bent a allen key stud, mushed a few of the saddles over, expected the shaft system to index itself and just started torquing down at 35ft lbs. had to call hughes and he sent out replacement components at my cost.
to answer your questions, about the lifters, and setting the lash, it takes awhile for my lifters to bleed off. hours. actually some of my valves are still open cold since over night. its ok to run the truck and warm it up alittle. the engine heat isnt all that bad to work with.
no it is not just good enough to visually watch the lifters close and set the valve lash. it depends on the cam, when how critical the adjustments are made. you and i can make adjustments at tdc or to be safe use the chart. at tdc FOR EACH CYLINDER the lifters are down and the combustion chamber is closed for an ignition stroke. some cams with a huge duration may be just hanging open too long to set at tdc. and with out knowing you might not be on a compression stroke! ramp angle on some cams is so slight, it can fool the eye and it isnt easy to watch and set the valve lash.
the object is to set the lash on the base circle. when the cam has no lift applied.
to be absolutely sure, use the chart.
when using the chart, the cam has the lift on the opposite side.
and there's still other methods. to adjust the exhaust valve when the intake just closes. then adjust the intake valve when the exhaust just opens. but i dont want to confuse. just use the chart.

No I get what your saying spun, I'm going to follow thee chart, I knew there was a pattern, but I didn't wasn't to question my buddy cause hes built a pretty nice engine........lesson learned, just glad I got the fuel sync out of the way!

i had problems with my lifters the first time i did them also
it happens

One way is to adjust the exhaust valve when the intake just closes. then adjust the intake valve when the exhaust just opens. but i dont want to confuse.
I did it that way for years.
On every thing from Corvairs to 9000 RPM sprint car motors.
Works good.

well my buddy just text me and said he already adjusted the rockers....said some were way to tight at 0 lash and others wernt tight enough....last time john touches my motor...he can take his 700HP lightning and cram it up his.......any who, said the same back firing at 1400rpm is still there, like I said at 1400 RPM the computer jumps the timing to 28-30 degrees.....Sean said 28 is normal....my buddy said he was looking online and said that it should only be around 16-20 at 1400rpm so i asked Sean no word back yet. were going to pull the tune out of the engine and see what happens.

Also going to set it at TDC and take a pic of the rotor and post it on here let you fellas be the judge on the dizzy timing!