A buddy is here with me that knows these 350's really well. He's stumped too.

It's running so badly you would swear we were missing spark plugs. It's really rough, I almost have to have it floored in order for it to stay running, and when it is running, it's backfiring like crazy.

We checked timing, it's dead on and on the correct compression stroke (verified).

What else might we start checking?

Thanks,
Shayne :cheers:

 

Ok did you set the timing to 6* BTDC with the EST disconnected? I can't remember if we went over that or not yet. Superrams are notorius for vacuum leaks. You can get a can of ether and spray it around the gaskets. If your RPM go up you have a leak. Flooring it though definitely isn't right, thats not good. Make sure you have everything connected, TPS, MAF, etc.

 

With that EST disconnected, I can't even get it stable enough to run. I mean it is really, really bad.

 

Ok, then you didn't really "set" the timing yet. :) Do you have a timing light? Get that unplugged vacuum line taken care of first. :)

 

One of the 1st things I do on a fresh power-up, is get yourself a spray bottle with water in it.... let the motor warm up for a few minutes, even though its running poorly, power down and spray each header primary with water mist right away, if it steams off immediately, that cylinder is firing, if it doesn't, and just pools and takes 5-10 seconds to slowly evaporate, that cylinder is not firing. If you find a cylinder not firing... it gets easy troubleshooting from there.

Yeah, timing is very important... are you sure its right ? its easy to get the distributor off a gear when putting it in, as you know you line up the rotor to cylinder # 1 when # 1 is TDC on the compression stroke.... if whoever put this together didn't do this right, you'll be wayyy off and would account for your poor performance. Because the distributor will move over due to the cam gear you actually have to move the distributor over when sliding the distributor down.

Any codes ? Did the MAF wire get damaged while off the car ?

Set your TPS to .56 idle give or take a hair.

Too much valve lash can cause some very rough performance as I have found out... I recommend 1/4 to 1/2 turn below zero.

lots of little things.... pay attention to the details even if you think you've gone over them once before....

Also as Scorp said, the SR is prone to leaking, especially on the initial installation.... check it closely.

good luck
Beach Bum

 

Listen to Beach, he da man!

 

Did you reset your IAC and TPS sensors??? If not, check tech tips it's there somewhere.

 

Reset idle air control too?

 

If he didn't mess with the throttlebody while it was off the car it "should" still be ok. Mine needed no readjustment when I put my SR on.

 

Correct, I didn't mess with it.

I'll tell you what I did do that I'm now not thrilled about the prospects. I might have to take this all apart anyway to get a vacuum leak out. We got it running with the pedal at half throttle and sprayed some carb spray right near the runners where the fuel injector lines sit. It smoothed right out for a second and then it was right back to the same 'ol crap.

Vacuum leak somewhere right?

 

Its possible, yes. Get as many of the other things set before you come to that conclusion since its a pain. I promise it gets easier every time. :)

Did you tighten all of the runner bolts before putting the plenum in place?

 

I agree with Beach Bum
I think the distributor off a tooth (or even out by 180º) is the most likely.


Do this....pull all spark plugs so the motor is easy to turn over by hand (by ratchet or breaker bar on crankshaft bolt.) Now, remove the distributor cap and mark a line on the bottom half of the distributor where No.1 spark plug wire position is.

Next you place your finger/thumb over the No.1 spark plug hole while your helper slowly turns the crankshaft in the normal rotation direction (clockwise when looking at the motor from the front of the car). When you feel air pressure forcing out past your finger from the No.1 cylinder, stop turning when the timing mark lines up to zero degrees.

Now, you are at TDC of the compression stroke on No.1 cylinder. Make sure the distributor rotor is directly on the mark you made where the No.1 spark plug wire terminal is, and you should have no problems from this point with timing.



[Modified by BBA, 11:13 PM 7/10/2003]

 

I assume your referring to an Accel / Lingenfelter Super Ram on an L-98.
if so It sounds like you may be a tooth off on the distributor. I had had to mount my distributor twisted from the stock position to get it to fit. I also found a serious leak between the passenger side rear runner and the intake manifold. The EGR slot in the runner was milled below the gasket line. It showed up on the dyno runs. Check for a major vacuum leak. :banghead: :banghead: :banghead:

 

Do what BBA said. :yesnod:

The center bolt on the crank pulley is 16mm so you know what to use. I PURPOSEFULLY install my distributor so that it is twisted 1/4" counterclockwise than normal. This gives me lots of room to move it for adjustments. If I install it "correctly" the damn thing is slamming into the back of the superram by the booster connection.

 

Hate to ask! :rolleyes: You said the timing was dead on, but are you sure you
don't have some wires crossed? :rolleyes:

 

Also you HAVE to get that EGR solenoid plugged into those vaccum lines. otherwise all bets are off!! Your fuel pressure will be screwed up and be too high at idle also if the correct vaccum can't be created with that leak.

 

All very good responses. I will check more into it in on Saturday when I have a chance to go through it -- I have the kids tomorrow (not that anyone needs to know this, but I'm going through a really nasty divorce at the moment. I married someone going on 9 years, with three young kids who wants a divorce. Bishop calls a Molly Mormon or "Mormon Orthodox." :D :D Being LDS myself, it's a tough time to live with someone who is that fanatical about religion, no matter what faith you are. I'm religeous I guess you could say, but not nearly to the level she is and that is worth breaking up a marriage with kids over :confused: :confused: :confused:) Anyway it's been on my mind a lot. I finally had had enough and moved out over a month ago.

I'll try to find some of these leaks and get them taken care of before bothering anyone else with posts.

Yep, no question about it.

I didn't mention this but my buddy builds race cars, works as a manager from AutoZone, and this is about the first thing we tried since it was soooo rough. I have a surprising amount of twist room on the distributor as well which is cool, it's now just finding that leak(2).

Yes, Accel/LPE. Did you diliberately have to point the rotor off a tooth in another direction? The guy from AutoZone thought it looked really good. More than anything, a leak between the passenger side rear runner and the intake is about the right spot. I had to use some JB weld on that runner to put a corner of it back on because it cracked when tightening Is there a tightening sequence to those 16 or so bolts? I let it sit 24 hours but maybe it's cracked worse than I thought. I used a generous amount but will still check it again. It was on the flat piece of the runner that connects up to the SuperRam, and it seemed to go back into place nicely. I used a C-clamp with my lid off to hold it overnight.

Is there any way to check for vacuum leaks while the car is off? My guess is probably not.

Thanks,
Shayne


[Modified by sspackman, 2:27 AM 7/11/2003]

 

Sounds to me like the wires got mixed up when you were installing them. For it to shake that bad. I did it once :bb Lapse of memory I guess. :jester

 

Quote: I had to use some JB weld on that runner to put a corner of it back on because it cracked when tightening

:skep: :banghead:

 

well having installed the super ram many times durring testing IM BETTING ON A SERIES OF SMALL VACUME LEAKS
check for a loose ,cracked, or disconnected vacume hoses or a vacume leak at the runner/plenum or runner /base gaskets, running a garden hose over all suspect leak points works but is messy and can screw your ignition, as the engine tends to drop rpm if it starts sucking water into a vacume leak but waters messy


the way I find vacuum leaks is clean and easy with no mess. get a propane torch,


(DONT LIGHT IT) just SLIGHTLY open the valve so its allowing gas to flow at a low voluum,start the engine and let it idle at the lowest speed you can then place the tip of the UNLIT torch at any suspected vacuum leak and listen for the rpms to increase and watch the tach, gas flowing into a vacuum leak will increase engine speed. JUST USE COMON SENCE AND DON,T CATCH THINGS ON FIRE IF YOU SOMEHOW MANAGE TO GET THE TORCH LIT


[Modified by grumpyvette, 2:23 PM 7/11/2003]