86 260 Timing

edcourter

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Timed a few cars with timing light. What are the dynamic numbers and setup (if any) for an 1986 Mercruiser 260/V8 (350), 4B Carb and electronic ignition. Where do we call one cylinder? Thanks
 

Bondo

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Ayuh,.... 8* Btc,... #1 is the forward left cylinder, just like every other SBC in existence,....

With the T-Bolt IV, hook up the light, 'n shoot,.... No wires to change or move,...
 

edcourter

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Thanks, Can do. So 8D BTC @ idle, (650RPM). No jumpers no shunts. Should I check it at another RPM to see if its advancing?
 

Scott Danforth

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30 degrees total advance by 2800 RPM (8 degree base, 22 degree advance)
 

edcourter

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On an older engine you would measure the damper diameter, compute the degrees and put a 30 degree mark x inches from TDC. With the electronic ignition (no vacuum, no fly weights), could you just check that its advancing to a visual 30 degrees and assume its probably working as intended? Thanks for the help
 

Bondo

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could you just check that its advancing to a visual 30 degrees and assume its probably working as intended?

Ayuh,... It either works,..... or it don't,.....

I've never checked for the stated full advance, 'n never had a problem,...

T-Bolt is a fine ignition, 1 of the Best,....
 

boatman37

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Most timing lights have a degree dial so tape isn't needed

yep. get a light with an advance dial on it. check it for base then turn the dial to 30 and check it at higher RPM. should read 0 on the damper if your light is set at 30 and your timing is accurate. BTW-i tried one of those tapes years ago and it flew off as soon as i started the engine. went with fluidamper balancers after that. already had the marks on it :joyous:
 

Scott Danforth

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On an older engine you would measure the damper diameter, compute the degrees and put a 30 degree mark x inches from TDC. With the electronic ignition (no vacuum, no fly weights), could you just check that its advancing to a visual 30 degrees and assume its probably working as intended? Thanks for the help

older Volvos came with timing tape. for the $3 its a good investment.

all performance dampers have timing info engraved the outer diameter. stock does not, however like many have stated, most timing lights have an advance knob.

I only check full advance if there is a problem. the dizzy either advances or it doesnt.
 
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