36 degrees timing, 15 lbs and no detonation on 91 octane?

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Sep 29, 2008 | 07:10 AM

#11

Spoolin

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Damn that's a lot of timing!!

how fast are you spinning that motor?

Sep 29, 2008 | 04:58 PM

#12

parish8

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From: omaha ne

Quote:

Originally Posted by Spoolin

Damn that's a lot of timing!!

how fast are you spinning that motor?

it is a lot for a ls motor. no idea if it is a lot for an hemi or whatever they call that engine series. i hear of a few motors needing 30deg even under a fair amount of boost.

i have been told a more efficient heads needs less timing. not to slam dodges but i am betting that that engine set up is not nearly as efficient as something like the afr headed 408 i had in my truck.

Sep 29, 2008 | 10:52 PM

#13

MikeGyver

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From: Suburban Chicago

Quote:

Originally Posted by 408 Sleeper

The shop doing the dyno work uses EGT, wideband O2, the dyno and audible and years of tuning to detect detonation.

Quote:

Originally Posted by parish8

^^^ with race gas i hope

It astounds me that F.A.S.T. doesn't have some kind of knock control. If detonation is indeed kept in check the old fashioned way, I would have race gas in it all of the time.
On the same note, is it possible that F.A.S.T. is using knock sensors, and retarding the timing a lot?

Sep 30, 2008 | 12:22 AM

#14

408 Sleeper

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From: St George UT

I spin the engine to 5800
The F.A.S.T. does not have any knock control for the Dodge
I checked with Kenny Dutwiler today. He said the timing needed and the higher EGT's are due to the 7:5-1 compression ratio. He reccomended going with 8:5-9:1 on the next engine.

Oct 1, 2008 | 08:56 PM

#15

hemidup

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Quote:

Originally Posted by 408 Sleeper

I take it your running a 1975 year or later LA block? Your pushing it with 600 hp even with a partial fill. An R block is much better suited for your needs. Who's heads and valvetrain are you using?

Oct 1, 2008 | 10:16 PM

#16

Hawk179

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Quote:

Originally Posted by parish8

i can give some insight to an ls motor.

i tried 15deg of timing and as much boost as i could before knock. then i uped the timing to 19 or 21 deg and worked the boost up till i got knock. there was significantly more power at 15deg and more boost then 21deg and less boost.

i did gain power adding timing from 15deg up to 21 so it isn't that 21deg was just to much.

i think you could make more power droping the timing back a little are running more boost. that being said i dont know that i would try it. you are running parts that are as far as i know not proven at those power levels. it would be best to run some race fuel and ensure that there is no detonation and then turn it up. that way if it blows up you know you found the limit of the parts and it wasn't detonation that took them out.

if your set against race fuel then maybe some meth?

Thats common. Boost will always make power over timing.

Oct 2, 2008 | 06:20 AM

#17

408 Sleeper

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From: St George UT

I am using the 1997 block that came in the truck. It was decked, line honed and bored .030 and then sonic checked. It has ARP main and hear studs. Using JE forged pistons(7:5-1), Childs & Albert rods and a SCAT cast crank. The heads are Fastman Magnum RT's(iron), with extensive porting, Crower roller rockers and an M1 4b intake that was ported.

My new engine assembly uses a 1999 5.2 bock that has been modified to 440 cid. It is a Speedomotive UMBR block, http://www.speedomotive.com/news.aspx
Has Crower billet rods, Mopar Performance forged crank(early US made model), Ross turbo pistons, coated (8:25-1), Milodon gear drive, Edelbrock Magnum RT heads with Hughes Engines Stage 5 CNC porting 2.06-1.60 valves. I will be using a Comp Cam 236-236 .580-.572 with a 114 LS and installed at 112. I will keep the existing intake manifold and rocker arms.

Last edited by 408 Sleeper; Oct 3, 2008 at 12:38 PM.

Oct 9, 2008 | 02:30 AM

#18

mrkindweiler

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From: Cypress, Ca

Quote:

Originally Posted by 408 Sleeper

My new engine assembly uses a 1999 5.2 bock that has been modified to 440 cid. It is a Speedomotive UMBR block, http://www.speedomotive.com/news.aspx
Has Crower billet rods, Mopar Performance forged crank(early US made model), Ross turbo pistons, coated (8:25-1), Milodon gear drive, Edelbrock Magnum RT heads with Hughes Engines Stage 5 CNC porting 2.06-1.60 valves. I will be using a Comp Cam 236-236 .580-.572 with a 114 LS and installed at 112. I will keep the existing intake manifold and rocker arms.

sounds like one hell of a motor!!! any pics of your current set up??