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Discussion Starter · #1 ·
I just had my 160 P-pump rebuilt and the timing pin was set at 18*. I am wanting to pin time it because I don’t have the tools to set timing myself and would like to set it and just be done with it. I am worried 18* is too much and will risk blowing a head gasket. Engine is a 95’ 12 Valve with BHAF, DDP economy injectors, Steed Speed Exhaust Manifold, Stealth 64 turbo and 4” exhaust, all stock internals. I’m also running an NV4500. What do you guys think? Will this setup last or am I asking for trouble at 18* timing? Here are the pump specs below. I’m not too savvy on pump numbers so not too sure what they mean.
Pump info:
0402736838
SN: 46800 19826
131 dv's
stock dv holders
high lpc setting (timing lift charts not accurate)
0 plate
modified afc (45 psi full travel)
3500 rpm kit
pinned at 18* btdc

max- 360cc
4- 340cc
3- 300cc
2- 250cc (set)
1- 200cc

0 psi boost- 110cc (afc in middle +0 preboost)
25 psi boost- 250cc

Thanks
 

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Not a pro on the P7100 but most articles I've read say 16 deg is where most set the pump. That's probably the one that is considered very safe. Have also read of owners running higher levels with no issues but I always lean to the safe side. Sort of curious why you are running a 0 torque plate. The most popular seems to be a #10 which gives a good mix of mild manners and high performance. Have read lots of arguments about the 0 and the 100. I guess which one you select depends on the overall performance goal.
 

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Discussion Starter · #3 ·
I did not spec the pump, I told the builder I had a goal of 300hp with the mods that I have and would like to prioritize reliability over power. Again I’m not a pro on p-pump specs this is just what was built for me.
 

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You may have more turbo than needed for 300 HP but don't guess it will hurt. It really doesn't take much to get a P pump to that power level. Don't really know about your injectors. I'd shy away from companies who rate them by HP gain. That's just sales hype. Stock injectors can do more HP but simply turning up the pump and turbo. Injectors should show a rating as to hole size and quantity in the tip. I'd almost be a 5x.012 Bosch injector would do what you wanted and cost less.
 

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Discussion Starter · #5 ·
I’m running DDP Economy injectors, they are supposed to be a slight performance gain over stock, it think like 10hp. It’s advertised as a quality stock injector replacement. I went with the stealth turbo because it also said it was suitable as a stock replacement with room for performance boosts and boost is set at 35psi. My concern was that I’ve read a lot of posts that say 16.5* is the most timing that you want on a stock head gasket.
 

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That timing number is pretty much what you find as the standard most go with. There are always people who run more and say they have no problem at all. If you wanted to be absolutely sure you could have the head O ringed and install studs instead of the head bolts. The studs would be recommended even with a stock gasket setup. Your injectors just sound like basic stock units. 10 HP is nothing. Stock units can do that with no sweat and a whole lot more. Stock 160 injectors are 5x.095. The 215 HP was 5x.01025. The 330 HP marine was 5x.011. The 370 HP marine was 5x.012 and the 435 HP were 5x.014. So most engines in the 160-190 HP used essentially the same size injector.
 

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The general rule of thumb in the 12v performance world is 16* is as far as you want to go if you really want to not have to worry about head gaskets. Beyond that, you're risking losing the head gasket if you are on stock bolts. You can re-torque the stock bolts however. I did that with mine. I'd double check the number to be sure. But I believe I went to 135ft/lb and it held a lot of abuse for a lot of years before I had studs installed. I was only at 15.5* of timing, but a dumped a shit load of fuel and air in it lol.

One thing to keep in mind, more timing also slows turbo spool. So with that big 64mm turbo and an nv4500, you're sacrificing spool up a bit at 18* of timing. More timing does help control EGT's in the higher rpms. So it's a give and take. If you don't ever want to pull the head? I'd back it off to 16* and leave it there. If you aren't worried about doing a head gasket at some point, leave it at 18* and hammer down.
 
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