Ok so my friend came over today and we advanced his timing a tooth. (same guy who has the goerend converter that I posted about before) We also got a metric dial indicator and the adapters to check the timing. It is too far advanced now, we need to back it off but we ran out of time to put the timing tool on it to see where it really is. Here is his sig from DTR so you can see his mods.
1993 w-250 4x4 dual 6'' mitre cut stacks,4 inch dp,Bhaf, ATS Manifold, 435 injectors,62/65/12, new ve pump(tweaked), new A518 trans,Gorend TC, 3200 gov. spring, Raptor 100 eletric pump,AFC lever gone, Isspro Gauges, tach, pyro, boost,tranny, fuel pressure, custom 5 pillar gauge holder
What do you guys think would be a good starting point for setting his timing?
435's and timing
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435's and timing
by SOOT4BRAINS » Fri Sep 11, 2009 8:53 pm
93 D250 Rag 3.54, 4 inch stans downpipe to custom 4 in exhaust, pump cranked with m3 pin, 366 spring, tach,boost,pyro,fuel pressure, ddp 70lpm sticks, 62/65/12 s300, airdog 150, rebuilt getrag, 3250 SBC clutch, helix 2 camshaft, dual redtops, new paint.
- SOOT4BRAINS
- fuel screw!!!!
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by Begle1 » Fri Sep 11, 2009 9:14 pm
Timing is really not a precision operation by the time the engine is molested to that degree...
If the truck's heavy, start with an 1/8" bump. If the truck's a toy, start with the pump to the head. If the truck's a toy with head studs, jump a tooth and go from there.
When it sounds really sharp under acceleration but doesn't pulse or shudder, you got it set good.
If the truck's heavy, start with an 1/8" bump. If the truck's a toy, start with the pump to the head. If the truck's a toy with head studs, jump a tooth and go from there.
When it sounds really sharp under acceleration but doesn't pulse or shudder, you got it set good.
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Begle1 - 14mm rotor
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. The tranny shifts at 23-2400 rpm under full acceleration. We put some springs in the valve body to prolong the shifts and it made low to mid rpm shifting much better, but it still shifts early going full bore. If you hold it in gear manually it feels like its kinda tapering off on top end and I think the tranny is seeing the power taper off and shifts. We already had the timing to the head. Others on DTR have told him that 435's like a lot of timing. He thinks he should be getting more power with these injectors and he has been nagging me daily to help him jump a tooth so we did it today. So now its really advanced.... still sounds ok, a little more "crack" to it, but not bad, no goofy sounds. But now it has 10 psi less boost and is a dog compared to before. So we are going to back it off tomorrow and slap the timing tool on there. Any body know how many mm's a 1/8 inch bump is roughly? How far is too far without having head studs? I know advancing timing will increase your cylinder pressure without nessecarily increasing your boost. 40 psi with a lot of timing could be as bad as 50 psi of boost with normal timing. Either way you can blow a head gasket. Thanks for the input Begle!
