Looking to make more low end power
TECH Fanatic




Joined: Aug 2009
Posts: 1,841
Likes: 252
From: Coast of San Mateo County Between Pacifica & HMB
FAST LSXRT definitely, MAMOFIED if funds allow, advance cam
2-4*, if thats not enough (should be 20-30 lb ft from 1500-4500
compared to now. don't know specs on v2 but Cam Motion stage II
truck cam would help a bunch more as well.
Alternately TBSS Intake ported by Peak Speed,
would be close to Fast in performance out of the box,
for much less than 1/2 of LSXRT price, + the cost of shave & dip,
don't know what that would be.
i
2-4*, if thats not enough (should be 20-30 lb ft from 1500-4500
compared to now. don't know specs on v2 but Cam Motion stage II
truck cam would help a bunch more as well.
Alternately TBSS Intake ported by Peak Speed,
would be close to Fast in performance out of the box,
for much less than 1/2 of LSXRT price, + the cost of shave & dip,
don't know what that would be.
i
Play with EOIT injection timing in your tune as well. That cam is big enough you can pick up a lot from delaying when injection timing starts. It makes little to no difference up top since the injector is open most of the time anyway. But down low, it can have a huge impact on performance in the range where that stall is likely to be slipping during street driving. It also improves the idle.
Play with EOIT injection timing in your tune as well. That cam is big enough you can pick up a lot from delaying when injection timing starts. It makes little to no difference up top since the injector is open most of the time anyway. But down low, it can have a huge impact on performance in the range where that stall is likely to be slipping during street driving. It also improves the idle.
It's a parameter for when to fire the injector in the cycle.
Delaying it can really boost low-end torque on larger cams. They are "later" than stock in terms of the overlap cycle, and spraying later will ensure you maximize time on a hot intake valve. Otherwise, you're spraying earlier than you need to (at low speed).
Honestly, you're probably see more power from that than the intake change. Or do both and really up the torque.
Delaying it can really boost low-end torque on larger cams. They are "later" than stock in terms of the overlap cycle, and spraying later will ensure you maximize time on a hot intake valve. Otherwise, you're spraying earlier than you need to (at low speed).
Honestly, you're probably see more power from that than the intake change. Or do both and really up the torque.
It's a parameter for when to fire the injector in the cycle.
Delaying it can really boost low-end torque on larger cams. They are "later" than stock in terms of the overlap cycle, and spraying later will ensure you maximize time on a hot intake valve. Otherwise, you're spraying earlier than you need to (at low speed).
Honestly, you're probably see more power from that than the intake change. Or do both and really up the torque.
Delaying it can really boost low-end torque on larger cams. They are "later" than stock in terms of the overlap cycle, and spraying later will ensure you maximize time on a hot intake valve. Otherwise, you're spraying earlier than you need to (at low speed).
Honestly, you're probably see more power from that than the intake change. Or do both and really up the torque.
Not sure if I did something wrong or what but I didn't notice any real change with my EOIT settings.
To be fair though I think at the time I was also fighting a corrupted tune file and am not sure if the current tune I am running has the changes to the EOIT table.
To be fair though I think at the time I was also fighting a corrupted tune file and am not sure if the current tune I am running has the changes to the EOIT table.
http://www.circledspecialties.com/p-...converter.aspx
Subbing to this thread. Can't wait to see some good, real world results.
BTW - yes a TBSS manifold is almost as good as a FAST and yes, it is ugly as F. But what about running it and then putting an engine cover on it? Could custom paint one cheap and have it look really nice for not much money.
I was making 400hp with the stock exhaust in my 99TA and it ran awesome from bottom to top end. I raced a bunch of modded street cars and I can't remember ever losing. I raced a highly modded yellow limited edition TA, on the bottom I walked away from him like he turned off the key. After we stopped to talk, he was pissed I took him so badly with minimum mods. He had full headers blaa blaa blaa.
My 01 WS6 has the stock exhaust with a stainless flow master welded in. Its not the loudest, its not the best flowing BUT it matches the engine and street driving PERFECTLY. The car MOVES HARD from bottom to top and makes me smile every time I touch the skinny pedal.
We'll I'm ditching the turbo 350 and going with a 4l80e that I just had built. Looking for a converter now. Probably going with a Yank 3400 stall. Plus I'm still doing the fast 102 lsxrt and building some type of cold air kit because my ait were pretty high. Is that 4l80 gonna rob power compared to the turbo 350?
Joined: Aug 2007
Posts: 24,241
Likes: 89
From: Turnin' Wrenches Infractions: 005
Pretty poor terminology.
Choking it will cause you to lose low end. Don't believe me? Clog a converter.
I think the term you're looking for is proper scavenging, and it really only applies to headers. You want the exhaust to leave the head at optimal velocity so that it is forced out fast enough to create a low pressure area or "dead zone" behind it. That way it will be far enough from the valve to prevent it from sitting on the back of the valve and creating problems the next time that the valve is open.
With proper headers, there isn't any need for more exhaust at all. You could run open headers and retain all low end power.
Taking a mild setup or low-cube small cam engine and throwing on 1 7/8" or 2" headers with a dual 3" exhaust and straight-through mufflers is going to make it struggle down low.
Choking it will cause you to lose low end. Don't believe me? Clog a converter.
I think the term you're looking for is proper scavenging, and it really only applies to headers. You want the exhaust to leave the head at optimal velocity so that it is forced out fast enough to create a low pressure area or "dead zone" behind it. That way it will be far enough from the valve to prevent it from sitting on the back of the valve and creating problems the next time that the valve is open.
With proper headers, there isn't any need for more exhaust at all. You could run open headers and retain all low end power.
Taking a mild setup or low-cube small cam engine and throwing on 1 7/8" or 2" headers with a dual 3" exhaust and straight-through mufflers is going to make it struggle down low.
Pretty poor terminology.
Choking it will cause you to lose low end. Don't believe me? Clog a converter.
I think the term you're looking for is proper scavenging, and it really only applies to headers. You want the exhaust to leave the head at optimal velocity so that it is forced out fast enough to create a low pressure area or "dead zone" behind it. That way it will be far enough from the valve to prevent it from sitting on the back of the valve and creating problems the next time that the valve is open.
With proper headers, there isn't any need for more exhaust at all. You could run open headers and retain all low end power.
Taking a mild setup or low-cube small cam engine and throwing on 1 7/8" or 2" headers with a dual 3" exhaust and straight-through mufflers is going to make it struggle down low.
Choking it will cause you to lose low end. Don't believe me? Clog a converter.
I think the term you're looking for is proper scavenging, and it really only applies to headers. You want the exhaust to leave the head at optimal velocity so that it is forced out fast enough to create a low pressure area or "dead zone" behind it. That way it will be far enough from the valve to prevent it from sitting on the back of the valve and creating problems the next time that the valve is open.
With proper headers, there isn't any need for more exhaust at all. You could run open headers and retain all low end power.
Taking a mild setup or low-cube small cam engine and throwing on 1 7/8" or 2" headers with a dual 3" exhaust and straight-through mufflers is going to make it struggle down low.
The problem comes from the guys with small cam 4.8s or stock cam 5.3s running 1 7/8" race headers with a 3.5" collector and dual 3" exhaust complaining about lack off performance when they mash the throttle at cruising speeds. Lots of noise, but you don't really go anywhere.








