Disappointment at the dyno: 227 rwhp with afr165's and custom cam

[thumper460]

right on... sounds like it is just a Carb thing.. in a F/I world!! with the engine right.. ign advance set as I suggested.. the jets and powervalve sound right.. with the AOD and a mild driving.. you should see at least 20-23 MPG.. really consertive ( and driving like an old man..) possibly 25 mpg!! Higher octane will allow the ign timing I suggested and also stop any ping you HAD to have with the 83 stuff!! and compression IS POWER!! you can see as much as 25 HP more with compression... but you HAVE to make the engine compatiable to use it!! and you are on the right track... have fun, and dont get bummed on the stang... remember before there were computers.. we ALL had to tune!! LOL

Just me..................................

Thumper

 

[crazypete]

Ok, I'm running 93 ocane plus acetone now.

It almost seemed like the timing was jumping around a degree or so....I curved it to do 20 degrees at 2200 rpms. I then dialed in 18 degrees base. Took it for a run, felt real powerful. So I bumped it to 24....felt more powerful. I bumped it to 28 degrees and my timing light broke. It almost felt a little slower but I'm not sure.

I do my full throttle runs on the rte2 connector, which is like a highway that follows the highway like a long exit....up a damn steep hill for max engine load...and terminates at a light on the far end. Keeps the speeds down and no place for popo to hide. But it does make it difficult to tell 5 hp differences.

Anyways, I got a new light and set the timing to 30 degrees.

Well, I still cant hear detonation or pinging. I went through this before. I stopped at 30 but it feels like I could still give it more and more and more. I gave it 42 degrees last time before I heard marbles in a can.

Oh yeah, and the car stopped dieseling on shut down around 18 degrees base.

Maybe I ran the dyno test with retarded timing although
...my engine doesnt shake at all
...the TDC determined by sticking a screwdriver down #1 cylinder while hand turning the engine and feeling for piston TDC is damn close to the tdc mark on the balancer so I dont think I have a spun balancer.

50 degrees total? Whats the point of decreasing returns where I am pushing down on the piston on its way up?

 

[r.barn5.0]

yeah something is not right there.

I put down 260rwhp with AFR 165's, stock cam, 1.7rr's, full exhaust, SSI intake
and I thought that was way low.

I also just bumped my timing to 18* and it's running fine still.


are you setting your timing with the spout connector out?
sounds like you are leaving it in and messing with total timing.
you want to mess with "base" timing

 

[crazypete]

Nope, it's carbed and the dizzy is a fresh accel 5200(?) series. It has no vacuum advance just mechanical advance and base timing. Makes things much easier when I know whats doing the advance.

I can achieve full advance by hand revving the engine. Too bad the factory balancer marks only go up to....34 or is it 36? Either way, it's waaaay off the scale.

 

[Dark Knight]

64/66 jetting is way to close together, it's usually 8-10 sizes between primary and secondary side.
Why are you running acetone with the 93?

 

[Dark Knight]

yeah something is not right there.

I put down 260rwhp with AFR 165's, stock cam, 1.7rr's, full exhaust, SSI intake
and I thought that was way low.

Thats what I got too, about normal..

 

[crazypete]

64/66 jetting is way to close together, it's usually 8-10 sizes between primary and secondary side.
Why are you running acetone with the 93?

Really....oh. Most of the folks I've seen talking about jetting had the jets 2-4 sizes apart. Oh well, it's easy enough to toss jets in the secondary. I'll toss some 74's in the secondaries tonight and go climb a few more hills and see if it helps.

I did see a nice puff of black smoke when the car was on the dyno and the dude punched it so the mixture was nominal at least.

The acetone prevents detonation...like octane booster...reduces the surface tension of the gas and increases atomization and makes it burn easier. Good for 1-2 mpg or so. 4 oz per 10 gallons. It seems to be working since I am up to 50 degrees total timing right now with still no detonation.

 

[Dark Knight]

The black smoke didnt mean rich, probably just to big of an acc. pump shot..
No A/F ratio on the dyno?

 

[crazypete]

The black smoke didnt mean rich, probably just to big of an acc. pump shot..
No A/F ratio on the dyno?

I'm kicking myself for not having them do an A/F test. I guess I was way too bummed at the time to ask for it. So now it's plug reading, watching the autometer guage and listening for pinging/feeling power or lack thereof/stumbling or bogging and exhuast sniffing.

 

[tmoss]

if there is no rich or lean stumble associated with the pump shot and that wiff of black, don't worry about it.