Timing Chim 4.0 1996 serp

[Chim326]

Just a couple of quickies as bored at work with naff all else to do! Does 26 degrees @ 4000 rpm sound write for timing with the vacume pipe disconnected. Or should it be around the 30-32 as someone suggested. Also if the precats are removed would you expect to here what i can only descibe as an exhaust leak around the main cat although everything is airtight. And last of all is it common for the timing chain to tick on decel considering new manifold gaskets, new cam and followers and cam chain and sprocket.

cheers.

[V8 Animal]

Chim326 said:

Just a couple of quickies as bored at work with naff all else to do! Does 26 degrees @ 4000 rpm sound write for timing with the vacume pipe disconnected. Or should it be around the 30-32 as someone suggested. Also if the precats are removed would you expect to here what i can only descibe as an exhaust leak around the main cat although everything is airtight. And last of all is it common for the timing chain to tick on decel considering new manifold gaskets, new cam and followers and cam chain and sprocket.

cheers.

How do you set the degrees?
Ive adjusted mine by sound and a drive as i don't understand where the degree starts.
The car is much more responsive now infact pretty scary.

[CRE]

Timing should be set at 32 deg's with vaccuum off @ 4k, unless it starts pinking.

HTH

Jamie

[Chim326]

Have been using a dynamic strobe so you can set the amount of degrees on the gun,ie;26 degrees, once you have found your TDC mark it with tipex then rev engine to 4000 rpm and turn dizzy until tdc lines up with mark on the block.

[Chim326]

Cre, If I adjust to 32 deg's it's not pinking but as i said earlier it sounds like exhuast is leaking around main cat, and wondered if this was normal for a car that has had the pre cats removed, Have read some other threads which say that the under bonnet engine noise increases with pre cats removed.

cheers
Steve.

[CRE]

You do tend to find that there is a slight increase in noise under the bonnet, the noise that you would normally hear sounds just a little deeper and little more "hollow", which is exactly what I would expect from removing pre-cats. As for the exhaust sounding like its blowing by the cat, its not something I would expect to hear, but one mans exhaust blow is another mans tappet noise! By that I mean your definition of exhaust blowing could be different to mine.
Do you get the noise at all rpm / load conditions? Or only at high load and / or rpm's?

HTH

Jamie

[Chim326]

From idle up to about 2000-2500 rpm in neutral and in under load it sounds like if you took a standard 4 cyl car and split the exhaust at the middle box is what i would descibe the noise around my main cat although it is not leaking. under load above 2000-2500 rpm sounds awesome.

[That Daddy]

Yes the exhausts ring more when precats are removed dont mistake this for blowing,the header pipes just ring more,i can give you this info 1st hand because i have heard before and after,if you think you have blowing then hold a metre length of fuel hose to your ear then go round the pipes and joins while its running

[Chim326]

Maybe a direct line to you Daddy would be useful for me but a pain in the a... you, Thanks appreciate your comments. Have you tried exhaust wrap or webbing, do you think it might take out the ringing. Did not get a chance to do before and after when i took pre cats out as the engine was on the bench for a few weeks when i did the cat removal, Just thought I was doing somthing wrong as in timing because when you retire the timing so much the ringing dissipates. Thats why I questioned the timing value besause at 32deg's it sounds worse than ever.

Thanks
Steve.