New Heads / Cam Running like Cr@p

ChunkFunky · 04-23-2003, 06:49 PM

I know everyone's going to say it's the lashing, which in fact I wouldnt be surprised but here goes.

bolted everything up with the new heads intake and cam, I set the lash acording to the posts people have made about the subject. I started it up for the first time and it ran like crap... very rough. So I shut it off and started it again and it wouldnt start.. it only starts if I press down the gas pedal, all the way.. then it starts and idles awful. My guess is the lashing is not right.

Even though I followed the procedure I found that I could get to the point of ZERO lash by tightening the nut by HAND, then I would do the 3/4 turn with a ratchet, but some seemed to go way too easy with no resistance and others seemed to have a bit of resistance and seemed to even push down the valves as I made that last turn.

I'll pull the valve covers and re do them, is there anything I could have done wrong with the cam install or the harmonic balancer install, it's all kinda keyd stuff it only goes in one way... the cam is a line up the dots thing and the balancer has a groove.

I can do them while it's running I suppose... though that could be a mess I imagine right?

NotchJohnson · 04-24-2003, 12:53 PM

are you using the right pushrods?

NotchJohnson · 04-24-2003, 12:58 PM

Trick flow's use 6.750" pushrods by the way.

ChunkFunky · 04-24-2003, 01:28 PM

I should have doubled checked, but I bought all the stuff used, it was all in really nice shape though.. doesnt look like it had alot of miles... but in anycase.. it all came together, I presume they were the correct ones, though once I pull the valve covers to reset them I'll pull up a rod and check, I do recall they were CRANE and not TFS but I'm sure crane makes a 6.75, I know they arent stock ones.
-as

93GTDIN · 04-24-2003, 02:03 PM

sounds like a timing issue to me. Try moving the distributor a couple of teeth advance/retard.

Advancing the timing should help with a start. Try cranking it and having someone moving the distributor while you crank. Once you get it started, dont turn it off. Let the car idle for 10 minutes so the computer can learn the idle. IF the idle is REALLY bad, you probably have a vacuum leak. If at any time you werent sure you got a vacuum line on there quite right, you probably didn't. Air is very thin and fluid and will leak anywhere it can, guaranteed.

Other things to check:

spark plugs/wries. Make you sure you have all the wires going to the right cylinders. The car will start if you have them messed up, but its best to be firing on all 8. Sounds stupid, but its happened... to me.

EGR: This is a touchy subject. Depending on what year your EEC is, they have different dependencies on the EGR system being set up correctly. My friend disconnected his EGR/SMOG on his 90 and it runs fine. I blocked mine off in my 93 and the car wouldnt start. Hooked it back up and voila... So anyway, make sure your EGR solenoid works, has vacuum, is clean, doesnt leak, etc.

Fuel pressure, if you're adjustable, make sure you've got your FP set upper 30's.

Make sure the MAF is tight and plugged in securely.

Getting it started for the first time is all about timing, find the sweet spot, get it running, let the computer adjust, then go to 12-14 degrees or whatever you want to run.

OF course, all this is considering you have your valvetrain aligned properly.

A word on valvetrain adjustment:
Zzero lash does not mean hand tight. Zero lash is when the rocker begins to put friction on the pushrod, IE when you start to feel resistance, thats zero lash. Then, break out your handy dandy torque wrench and tighten to 20 lbs-ft. If it takes mroe than one full turn, you need shims. simple, right?

have fun
Dino

NotchJohnson · 04-24-2003, 02:16 PM

His rockers are stud mount.

ChunkFunky · 04-24-2003, 02:37 PM

I'm thinking my lifters had collapsed over the time I had the engine apart and that would explain the variance on the rockers, some tighter then others... since I've had it running (barely) I think I shoudl go redo all the rockers and I'm sure I'll be ok.. I just wanted to get other people's ideas on the situation, specialy since I've never done rockers before... well short of just bolting down factory stamped ones.
-as

86GT · 04-24-2003, 03:02 PM

Get the lifters pumped up with oil (prime the oil pump). Make sure the timing is good and then recheck all the valves. Check the plug wires to make sure they're in the right order.

04-23-2003, 06:49 PM	#1
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	New Heads / Cam Running like Cr@p I know everyone's going to say it's the lashing, which in fact I wouldnt be surprised but here goes. bolted everything up with the new heads intake and cam, I set the lash acording to the posts people have made about the subject. I started it up for the first time and it ran like crap... very rough. So I shut it off and started it again and it wouldnt start.. it only starts if I press down the gas pedal, all the way.. then it starts and idles awful. My guess is the lashing is not right. Even though I followed the procedure I found that I could get to the point of ZERO lash by tightening the nut by HAND, then I would do the 3/4 turn with a ratchet, but some seemed to go way too easy with no resistance and others seemed to have a bit of resistance and seemed to even push down the valves as I made that last turn. I'll pull the valve covers and re do them, is there anything I could have done wrong with the cam install or the harmonic balancer install, it's all kinda keyd stuff it only goes in one way... the cam is a line up the dots thing and the balancer has a groove. I can do them while it's running I suppose... though that could be a mess I imagine right? __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

04-24-2003, 12:53 PM	#2
NotchJohnson Registered Member Join Date: Oct 2001 Location: Florida Keys Posts: 593	are you using the right pushrods? __________________ 89 notch-finally not stock!! ported gt40's, ported cobra intake, 65mm tb, 75mm maf, mac cai, lt's,prochamber, fms 1.6 rr, 125 shot.

04-24-2003, 12:58 PM	#3
NotchJohnson Registered Member Join Date: Oct 2001 Location: Florida Keys Posts: 593	Trick flow's use 6.750" pushrods by the way. __________________ 89 notch-finally not stock!! ported gt40's, ported cobra intake, 65mm tb, 75mm maf, mac cai, lt's,prochamber, fms 1.6 rr, 125 shot.

04-24-2003, 01:28 PM	#4
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	I should have doubled checked, but I bought all the stuff used, it was all in really nice shape though.. doesnt look like it had alot of miles... but in anycase.. it all came together, I presume they were the correct ones, though once I pull the valve covers to reset them I'll pull up a rod and check, I do recall they were CRANE and not TFS but I'm sure crane makes a 6.75, I know they arent stock ones. -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

04-24-2003, 02:03 PM	#5
93GTDIN Registered Member Join Date: Jan 2001 Location: Live music capital of the world, TX Posts: 324	sounds like a timing issue to me. Try moving the distributor a couple of teeth advance/retard. Advancing the timing should help with a start. Try cranking it and having someone moving the distributor while you crank. Once you get it started, dont turn it off. Let the car idle for 10 minutes so the computer can learn the idle. IF the idle is REALLY bad, you probably have a vacuum leak. If at any time you werent sure you got a vacuum line on there quite right, you probably didn't. Air is very thin and fluid and will leak anywhere it can, guaranteed. Other things to check: spark plugs/wries. Make you sure you have all the wires going to the right cylinders. The car will start if you have them messed up, but its best to be firing on all 8. Sounds stupid, but its happened... to me. EGR: This is a touchy subject. Depending on what year your EEC is, they have different dependencies on the EGR system being set up correctly. My friend disconnected his EGR/SMOG on his 90 and it runs fine. I blocked mine off in my 93 and the car wouldnt start. Hooked it back up and voila... So anyway, make sure your EGR solenoid works, has vacuum, is clean, doesnt leak, etc. Fuel pressure, if you're adjustable, make sure you've got your FP set upper 30's. Make sure the MAF is tight and plugged in securely. Getting it started for the first time is all about timing, find the sweet spot, get it running, let the computer adjust, then go to 12-14 degrees or whatever you want to run. OF course, all this is considering you have your valvetrain aligned properly. A word on valvetrain adjustment: Zzero lash does not mean hand tight. Zero lash is when the rocker begins to put friction on the pushrod, IE when you start to feel resistance, thats zero lash. Then, break out your handy dandy torque wrench and tighten to 20 lbs-ft. If it takes mroe than one full turn, you need shims. simple, right? have fun Dino __________________ 96 Cobra - a bit too stock. 14.0 @ 101

04-24-2003, 02:16 PM	#6
NotchJohnson Registered Member Join Date: Oct 2001 Location: Florida Keys Posts: 593	His rockers are stud mount. __________________ 89 notch-finally not stock!! ported gt40's, ported cobra intake, 65mm tb, 75mm maf, mac cai, lt's,prochamber, fms 1.6 rr, 125 shot.

04-24-2003, 02:37 PM	#7
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	I'm thinking my lifters had collapsed over the time I had the engine apart and that would explain the variance on the rockers, some tighter then others... since I've had it running (barely) I think I shoudl go redo all the rockers and I'm sure I'll be ok.. I just wanted to get other people's ideas on the situation, specialy since I've never done rockers before... well short of just bolting down factory stamped ones. -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

04-24-2003, 03:02 PM	#8
86GT Sniffed too much n20 Join Date: Oct 1998 Location: Ont, Canada Posts: 1,018	Get the lifters pumped up with oil (prime the oil pump). Make sure the timing is good and then recheck all the valves. Check the plug wires to make sure they're in the right order.

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