460 timing and tuning help

Hello all!

Like the title states I need help with the timing and tuning of my 460. It is suffering from pinging / detonation after it reaches 200 dresses (reaches this temp when at stop light) and at around 2000 rpms under load. If the temp is under 190 I'm good.

Here are some specs: 79 block dove-c heads dyno at 525 hp and 550

Dove-c heads
.30 over flat top pistons,
stock crank,
Dove c heads,comp cam(hydraulic flat tapper rpm range 2000-6000 valve timing .006)
magnum roller rockers,
mighty demon carb,
msd distributor
on 79 block 460.

Does any oh have a setup similar to this and if so where do you have your timing set at to avoid pinging / detonation?????

Also would running to lean and carbon cause this?
Your help is greatly appreciated!!!!!

https://www.429-460.com/t22813-total-timing-with-10-51-compression Check this thread, it has a lot of good info.

Depending on how things stack up you could be up over 11.5:1 compression which will give you a lot of trouble running on the street with pump gas at real world 200 degree operating temperatures. I don' t think it's practical.

DaveMcLain wrote:Depending on how things stack up you could be up over 11.5:1 compression which will give you a lot of trouble running on the street with pump gas at real world 200 degree operating temperatures.  I don' t think it's practical.

X2

Any recommendations?

I her retarding the timing and using a 160 thermostat so keep the engine hitting 200.

If it doesn't hit 200 I'm good. I know I have to tune that carb. It stinks like gas. Lol



By the way supervel45 thanks. I will check it out.

There was an article in Car Craft magazine (Aug. '99) where they were power tuning a 429 in a '69 Cougar, they found an extra 18.8hp and 29ft lb just by changing the T-stat from a 195 to a 160. I realize there are many other factors/parameters involved to see such results, but a positive result power-wise none the less from such a simple change.

DaveMcLain wrote:Depending on how things stack up you could be up over 11.5:1 compression which will give you a lot of trouble running on the street with pump gas at real world 200 degree operating temperatures.  I don' t think it's practical.

I don't know how its running on pump gas now with D0VE-C's and flat tops

Put in better gas and see how it works.

nice! I had no idea by changing the stat to 160 who increase the hp that much. If I keep the temperature under 190 it won't ping is what I noticed.

Regard gas. I run 93 octane but then started adding octane cuz I heard that might help but still running hot at stop lights. One thing I noticed is that it stinks of gas to the point where it Botha my eyes sometimes.

[quote="Tigger!"]nice! I had no idea by changing the stat to 160 who increase the hp that much. If I keep the temperature under 190 it won't ping is what I noticed.

Regard gas. I run 93 octane but then started adding octane cuz I heard that might help but still running hot at stop lights. One thing I noticed is that it stinks of gas to the point where it Botha my eyes sometimes. [/qu                                                                                       "But then started adding octane cuz", You would not be refering to octane booster, would you?

I will be changing my thermostat to 160 today. Lol.

I'm guessing it'll still get hot when not cruising. When they run hot at rest, it usually indicates an airflow problem....shroud, fan or a combination of the two. You're running an electric fan or fans, right?

I have a big dual fan with shroud.

Would running to lean cause this because I'm almost 100% sure I'm running lean.

Tigger! wrote:nice! I had no idea by changing the stat to 160 who increase the hp that much. If I keep the temperature under 190 it won't ping is what I noticed.

Regard gas. I run 93 octane but then started adding octane cuz I heard that might help but still running hot at stop lights. One thing I noticed is that it stinks of gas to the point where it Botha my eyes sometimes.

Are you running octane booster? If it's burning your eyes, I doubt it's running lean.

What I meant to say is the it stinks of unburt gas. Sorry.

Might to check your manifold vacuum and power valve. It may be bad, or not a low enough one to close because of not enough vacuum caused by a large cam.

supervel45 wrote:Might to check your manifold vacuum and power valve. It may be bad, or not a low enough one to close because of not enough vacuum caused by a large cam.

SUCCESS!!!!!!!

Set distributor to run without vacuum advance and set timing at 36 degree total.