I lost 82 RWHP, Need Help!

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Jul 3, 2009 | 08:45 AM

khenry

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From: Brazoria, Texas

I lost 82 RWHP, Need Help!

I have a LS1 bottom end PRC stage 2.5 heads, MS3 cam 42 lb injectors/255 pump, MSD coil packs. In January this year I got a dyno tune and made 439hp.I installed a 150 shot wet kit and NGK TR-6 plugs and took it back to the tuner to tune it for the nitrous, he pulled 4 degrees of timing and before the spray it only hit 358hp.Is this 82 hp loss possible from just different plugs,and pulling 4 degrees of timing, and or possibly the temperature difference on the dyno from January to June?(I checked compression and everything looks great)Any wisdom would be great!

Jul 3, 2009 | 09:41 AM

Intercooler2

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Well does your *** dyno say it lost that?

Jul 3, 2009 | 09:47 AM

Patrick G

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Check your plugs, wires, and coils. Most likely you have dead spark in one hole. Are your wires and coils stock GM or aftermarket?

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Jul 3, 2009 | 10:41 AM

black01_WS6

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I had a similar problem, turned out that my MSD wires were all reading differently, and one was completly shot.

If you lost that much HP you should be able to tell by the seat of your pants- if you know what I mean.

Jul 3, 2009 | 01:02 PM

thunderstruck507

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Wouldn't he have a noticeable or at least scannable miss if he had a dead hole?

Curious because I'm trying to find about 40-50rwhp in my car.

Jul 3, 2009 | 01:08 PM

khenry

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My plugs are new, and the coils and wires are MSD that look all to be good.

Jul 3, 2009 | 01:30 PM

Duffster

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wires are funny. . . do resistance checks on ALL of them. Should be low low resistance (maybe 3-15 Ohms each) It's a free check.

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Jul 3, 2009 | 01:49 PM

black01_WS6

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Most likely the problem is in the MSD coils. Put some stockers back in. also check to make sure all the wires are reading correctly, and plugs are good before buying or replacing anything.

Jul 3, 2009 | 01:52 PM

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Old SStroker

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Quote:

Originally Posted by khenry

Were both dyno runs on the same dyno? Can you post graphs of both runs?

Last edited by Old SStroker; Jul 4, 2009 at 08:20 AM.

Jul 3, 2009 | 01:58 PM

#11

Redlinez

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You could have joined the non-stock bottom end club like myself. Mine let a rod bearing go at the 430 mark.

Jul 3, 2009 | 02:11 PM

#12

thunderstruck507

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How much resistance would a plug wire have to have before it starts to cause a power loss? I have stock replacement truck wires on mine. I'm going to ohm them in a bit.

Jul 3, 2009 | 03:11 PM

#13

JScamaro

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I read that MSD shipped out a bad batch of plug wires. You could look into that depending when you got them.

Jul 3, 2009 | 03:56 PM

#14

02*C5

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The LS1 coils are great for being able to handle great power. The MSD coil packs have been known to be crap specially for LS engines. I had one of the guys I respect very much tell me that really you only want to add that to your LS1 engine when your 700+ RWHP. Go back to the stock coils you'll find those lost ponies.

Jul 3, 2009 | 06:31 PM

#15

austinsguitardude

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yea my car sat for over a year (joined the marine corps) and now that i drive it again it just doesnt feel the same, and i have not changed anything

Jul 3, 2009 | 06:41 PM

#16

squale iii

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4 degrees will hurt you n/a, but not that much I wouldn't think.. Get a timing tuner too btw, flick of a switch and you got all your timing when you're n/a..

Jul 3, 2009 | 06:44 PM

#17

Patrick G

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I didn't want to say it unless you had them, but go immediately and take off the MSD coils and wires and replace them with stockers. I have seen an insane amount of wires and coils by that company give a dead hole. No lie. If you still have your stock plugs and wires, replace them and redyno. You should find your problem.

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Jul 3, 2009 | 06:59 PM

#18

khenry

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I'll sure try it, thanks for the info guys!

Jul 3, 2009 | 07:08 PM

#19

mike13

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Like Patrick G said. Also you need to look at both graphs and see what's going on, does the powr aned torque climb slower or does the power fall flat at a lower rpm? All those things will give you a clue to what is going on.