Long story short, melted the 2 rear wires next to my DP, replaced them, dynoed the car, and its all of a sudden 100rwhp short. I made 507rwhp on 13.5psi, and now im making 408 or so.
So im thinking the 2 plugs in the back crapped out on me from the wires being melted. Changed all 8 plugs expecting to feel an immediate difference, but car feels the same.

Car doesn't seem to be missing and drives fine, pulls hard. doesnt crank weird or anything which I would think it would do if it was low on compression on a cylinder, no weird noises, nothing.

I havent redynoed but I would imagine 100rwhp would be easy to notice.
Both pulls were done on dynojets, different ones, but dyno jets have on calibration or anything.'

Any ideas?

 

May have washed the cylinders down. Fuel kept being injected without being burned. How long did you let this go before you replaced the wires?

 

just highjacking this post...

if you suspect the cylinders have been washed down what do you do?

 

do a compression test. If it's low, put some oil in the cylinder and see if the compression comes back. If so, it's rings/wall that's the issue. If not, put compressed air via compression tester hose with check valve removed into cylinder. With both rockers backed off, see where the air comes out. Valve cover breather = piston/rings. Throttle opening/intake = intake valve or seat. Out the exhaust = exhaust valve.

 

Welcome to the fabulous world of dyno numbers!

 

Was just thinking this too.

Have you ever run her down the track? Personally I think this is a better comparison if there's any span of time between tests.
Dyno runs back to back are fine for seeing differences in tune or trying different parts, but I trust the track more.

 

Routed the two wires to the wrong plugs? Swapped them?

 

Doesn't 507 sound kinda high for a 306 with 13.5 psi? Or was that with the meth injection? Did the injector quit working?? can you monitor the amount of methanol in the reservoir and see if its dropping?

 

Yeah I know dynos can be off... but two dynojets being off 100rwhp?.. thats a bit odd. Also, the torque was only off like 50ftlbs.

Unfortunately I never took the car to the track so can't go off of that.

The 507rwhp was with straight pump, the lower HP was with the meth... but an adequate amount of fuel was taken out.... and Im definitely spraying methanol now, or it would've grenaded by now lol.

I don't think 507 on 13.5lbs is a lot? I dont know... it has afr 185s, 9.5:1 and a 66mm with an S wheel.

 

i guess 507 isnt that high. But 408 is definitely low.... you have any way to check AF ratio and iat temps?

 

Umm, I think you'd notice if your car dropped 100 hp just by driving it. Does it feel any different behind the wheel or are you just talking dyno #'s

 

AF ratio is 11.8:1 or so. IAT i do not know.

Yeah its 408/456 now and was 507/510

 

It dynoed 507, never drove it with 507, It was missing and what not, fixed the misfire, and put it on a different dyno closer to home and it made 408. both dynojets

Changed plugs thinking plugs were shot, but didnt feel a SOTP difference... which I would imagine would be more than noticeable with 100hp added.

 

Heres the original dyno
#ad


and the 2nd dyno...
#ad


^the second dyno is actually higher PSI than I thought..hmm..

 

Could it be that you have slowed the burn down with meth and still running a pump gas tune caused a drop in HP ?

Dont really know ............. just thinking out loud .

Can you get it to a track ? MPH would give you a pretty close estimate of what its making .

Also , what gets me is that it made more HP with a miss

 

Don't think it was missing on that pull...that was one of the first.

 

were the first #'s without meth and the second dyno #'s with that tells ya whats wrong

my freinds 408 non intercooled blowthrought dose not like meth at all till we push the boost past 15 psi
it lost power with the meth on at 10 psi .6 10th in the 1/4

 

If anything it should be a cooler intake charge no?

 

If you got a radical drop in IAT (and increase in octane) from the meth injection you would need to add timing advance to get the combustion started earlier than with low octane pump.

 

I was already at 19degrees though...