N/A Lt1 timing tune.
Thread Starter
Racer
Joined: Jul 2004
Posts: 315
Likes: 15
From: Ornskoldsvik
N/A Lt1 timing tune.
Hi.. I´m trying to determine how much timing i can go with my street Lt1. The car has the following mods.
350ci. With fully balanced and ARP-bolted internals. hi volume pump, Standard pistons and rods with stock fully ported heads, ported intake manifold, 58mm TB, Clevite 77 bearings, msd 6al ignition, 36lb injectors, full lenght stainless headers w, X-pipe and dual 3" exhaust with no catalytic converters, 3200rpm converter, Th700 prepped gearbox. 255l Racetronix fuelpump, Beehive springs, comps retainers, comps hyd roller lifters and pushrods. Comps 1,6 Roller rockers and Comps 07-468-8 camshaft. Revlimit on the MSD is 7000rpm, but i dont rev that much... Dont know if i dare when running stock internals...
I use WB lambda when tuning.. I have been leaning out the fuelmap so the car runs well with the new injectors, i have left the timing stock for the moment. The car punches really good but i think i can get it to push out some more when ramping up the timing a bit. The A/F ratio is fine and i have no reports on any detonation for the moment. I was just thinking if any of you have a similar setup and what timing you use. I remember people running well over 35 degrees on similar setups but cant find where i saw it. On this Lt1 i think the highest timing on the map is 27 deg.. What do you think?
Thanks
/Svante.
350ci. With fully balanced and ARP-bolted internals. hi volume pump, Standard pistons and rods with stock fully ported heads, ported intake manifold, 58mm TB, Clevite 77 bearings, msd 6al ignition, 36lb injectors, full lenght stainless headers w, X-pipe and dual 3" exhaust with no catalytic converters, 3200rpm converter, Th700 prepped gearbox. 255l Racetronix fuelpump, Beehive springs, comps retainers, comps hyd roller lifters and pushrods. Comps 1,6 Roller rockers and Comps 07-468-8 camshaft. Revlimit on the MSD is 7000rpm, but i dont rev that much... Dont know if i dare when running stock internals...
I use WB lambda when tuning.. I have been leaning out the fuelmap so the car runs well with the new injectors, i have left the timing stock for the moment. The car punches really good but i think i can get it to push out some more when ramping up the timing a bit. The A/F ratio is fine and i have no reports on any detonation for the moment. I was just thinking if any of you have a similar setup and what timing you use. I remember people running well over 35 degrees on similar setups but cant find where i saw it. On this Lt1 i think the highest timing on the map is 27 deg.. What do you think?
Thanks
/Svante.
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
At 7000 rpms and the 95kpa MAP range the stock LT1 timing is 27*. But, if you look at 6000 rpms where the stock engine is done, the timing is 35*.
I would try increasing the timing to 35-37* and see how the power feels. My camshaft has 2* advance built in, and have also increased the stock timing by 2* in the upper MAP kpa areas. I see ~40* at WOT in the upper kpa range, and 0 spark retard.
I would try increasing the timing to 35-37* and see how the power feels. My camshaft has 2* advance built in, and have also increased the stock timing by 2* in the upper MAP kpa areas. I see ~40* at WOT in the upper kpa range, and 0 spark retard.
Thread Starter
Racer
Joined: Jul 2004
Posts: 315
Likes: 15
From: Ornskoldsvik
At 7000 rpms and the 95kpa MAP range the stock LT1 timing is 27*. But, if you look at 6000 rpms where the stock engine is done, the timing is 35*.
I would try increasing the timing to 35-37* and see how the power feels. My camshaft has 2* advance built in, and have also increased the stock timing by 2* in the upper MAP kpa areas. I see ~40* at WOT in the upper kpa range, and 0 spark retard.
I would try increasing the timing to 35-37* and see how the power feels. My camshaft has 2* advance built in, and have also increased the stock timing by 2* in the upper MAP kpa areas. I see ~40* at WOT in the upper kpa range, and 0 spark retard.
/Svante.
Thread Starter
Racer
Joined: Jul 2004
Posts: 315
Likes: 15
From: Ornskoldsvik
I have johan09@hotmail.com if you would like to e-mail it for me.
/Svante.
