Ls1 Trans Am vs. 1979 Firebird
07-18-2012, 09:44 AM
#21
On The Tree
Thread Starter
07-18-2012, 10:08 AM
#23
On The Tree
Thread Starter
I wasn't clear before. He had it tuned when its was a bolt on, M6 car. No tune since the ported heads and cam. The injectors are still stock but he has some 42 lb injectors ready to go in.
07-18-2012, 10:23 AM
#24
My car was tuned when it was aftermarket cam and bolt ons, but different cam and ported heads was still a HUGE change. He will not believe the difference it should make.
07-18-2012, 11:41 AM
#25
On The Tree
Thread Starter
Forgot to say nice kill and I saw you mention that so I had went back and edited the post too
My car was tuned when it was aftermarket cam and bolt ons, but different cam and ported heads was still a HUGE change. He will not believe the difference it should make.
My car was tuned when it was aftermarket cam and bolt ons, but different cam and ported heads was still a HUGE change. He will not believe the difference it should make.
Much nicer than mine! I like very much, yes
07-18-2012, 02:34 PM
#29
Staging Lane
Very, VERY close. I am impressed you could pick that up from the video. Compression is 10.5:1. The cam is a solid roller with the lash at .016/.018, 236/242 @.050 .564/.570 lift and then I put 1.6 roller rockers on. The LSA is 110. Timing is locked out at 35 degrees.
This car was actually a v6 but it does have power brakes. How much weight do you think it would save? I am also ditching the power steering for a manual steering rack.
This car was actually a v6 but it does have power brakes. How much weight do you think it would save? I am also ditching the power steering for a manual steering rack.
I assume you already know this info, but just in case you don't:
As far as the timing goes, "locked out" refers to filling in the slot in the plate that both the mechanical advance and vacuum advance rotate inside the distributor - it's the plate the rotor bolts onto : that point plus the initial idle timing is your total timing. Some guys don't use vacuum advance, and it looks like yours isn't hooked up either. Vacuum advance does help part throttle driveability and fuel efficiency...
Those Trick Flow 195 heads are fairly efficient, I'm thinking you didn't get your timing set on a dyno because I would have put money on it being around 32 degrees where best power is obtained (learned from experience). 36 degrees actual total timing with 10.5 compression even on your big cam setup (big cams help tame knock due to pressure bleed off from the cam overlap) it should be knocking! Or are you running race gas mix?
BTW a great rule to go by: the more efficient the heads, the less timing the engine will need. Old crap GM heads were so bad that I've seen a few well modded small blocks need 38 degrees for full power, while a setup like my current LS2 based 402 likes 26 degrees and some other LS engines even like 24 degrees. Helped do a 367sbc build (400 block, 350 crank- a 8,200rpm combo) with top of the line trick flow heads that liked 30 degrees.
Tossing the power brakes only saves a couple pounds, but it enables you to clean up the engine bay and also not require a vacuum canister to keep brake pressure up. I'd personally go that route again in a heartbeat.
I also had manual steering but damn that was hard work with any kind of normal sized tire on the front. So I installed the close ratio power steering rack out of an '81 Z28 (1980 and up Z28's had the much sought after close ratio) Personally I'd say thats only viable when you are running a big n little setup where the tiny front tire has less resistance to low speed turning.
07-18-2012, 04:04 PM
#32
On The Tree
Thread Starter
Guess I wasn't that close, half point of compression difference is alot AND it wasn't a flat tappet cam but a roller.
I assume you already know this info, but just in case you don't:
As far as the timing goes, "locked out" refers to filling in the slot in the plate that both the mechanical advance and vacuum advance rotate inside the distributor - it's the plate the rotor bolts onto : that point plus the initial idle timing is your total timing. Some guys don't use vacuum advance, and it looks like yours isn't hooked up either. Vacuum advance does help part throttle driveability and fuel efficiency...
Those Trick Flow 195 heads are fairly efficient, I'm thinking you didn't get your timing set on a dyno because I would have put money on it being around 32 degrees where best power is obtained (learned from experience). 36 degrees actual total timing with 10.5 compression even on your big cam setup (big cams help tame knock due to pressure bleed off from the cam overlap) it should be knocking! Or are you running race gas mix?
BTW a great rule to go by: the more efficient the heads, the less timing the engine will need. Old crap GM heads were so bad that I've seen a few well modded small blocks need 38 degrees for full power, while a setup like my current LS2 based 402 likes 26 degrees and some other LS engines even like 24 degrees. Helped do a 367sbc build (400 block, 350 crank- a 8,200rpm combo) with top of the line trick flow heads that liked 30 degrees.
Tossing the power brakes only saves a couple pounds, but it enables you to clean up the engine bay and also not require a vacuum canister to keep brake pressure up. I'd personally go that route again in a heartbeat.
I also had manual steering but damn that was hard work with any kind of normal sized tire on the front. So I installed the close ratio power steering rack out of an '81 Z28 (1980 and up Z28's had the much sought after close ratio) Personally I'd say thats only viable when you are running a big n little setup where the tiny front tire has less resistance to low speed turning.
I assume you already know this info, but just in case you don't:
As far as the timing goes, "locked out" refers to filling in the slot in the plate that both the mechanical advance and vacuum advance rotate inside the distributor - it's the plate the rotor bolts onto : that point plus the initial idle timing is your total timing. Some guys don't use vacuum advance, and it looks like yours isn't hooked up either. Vacuum advance does help part throttle driveability and fuel efficiency...
Those Trick Flow 195 heads are fairly efficient, I'm thinking you didn't get your timing set on a dyno because I would have put money on it being around 32 degrees where best power is obtained (learned from experience). 36 degrees actual total timing with 10.5 compression even on your big cam setup (big cams help tame knock due to pressure bleed off from the cam overlap) it should be knocking! Or are you running race gas mix?
BTW a great rule to go by: the more efficient the heads, the less timing the engine will need. Old crap GM heads were so bad that I've seen a few well modded small blocks need 38 degrees for full power, while a setup like my current LS2 based 402 likes 26 degrees and some other LS engines even like 24 degrees. Helped do a 367sbc build (400 block, 350 crank- a 8,200rpm combo) with top of the line trick flow heads that liked 30 degrees.
Tossing the power brakes only saves a couple pounds, but it enables you to clean up the engine bay and also not require a vacuum canister to keep brake pressure up. I'd personally go that route again in a heartbeat.
I also had manual steering but damn that was hard work with any kind of normal sized tire on the front. So I installed the close ratio power steering rack out of an '81 Z28 (1980 and up Z28's had the much sought after close ratio) Personally I'd say thats only viable when you are running a big n little setup where the tiny front tire has less resistance to low speed turning.
The timing I set at 35 degrees. I am not sure if they changed the timing or not when I left the car at a local shop to be tuned. He is pretty meticulous but never mentioned adjusting the timing. I will have to look into that.
As far as knocking goes I haven't heard any at all. I run just pump 93 octane. Like I said above I'll check with the guy who tuned my car if he adjusted the timing cause now I am curious.
Yes, I will be running a big and little set up as soon as it is the budget.
07-18-2012, 04:06 PM
#33
On The Tree
Thread Starter
07-18-2012, 06:19 PM
#35
On The Tree
Thread Starter
07-18-2012, 08:40 PM
#36
Staging Lane
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D79..great runs, loved it, but was it me or was your 'bird not upshifting as quick as possible..i had a problem with my '79 as well...it just seemed stuck in a lower gear...maybe it was just my perception of the race...love your car and that color.
07-19-2012, 12:31 AM
#37
It's not that nice in person, but thanks man
{snip}
I really can't wait to rebuild the rear end and make the car MUCH more fun. My first gear runs up to about 60-65 mph, and second gear is good to 120-130 mph, third gear... well I know what the math says but I am never going to find out. I hope the gear change will help keep the cars momentum going.
This car was actually a v6 but it does have power brakes. How much weight do you think it would save? I am also ditching the power steering for a manual steering rack.
{snip}
I really can't wait to rebuild the rear end and make the car MUCH more fun. My first gear runs up to about 60-65 mph, and second gear is good to 120-130 mph, third gear... well I know what the math says but I am never going to find out. I hope the gear change will help keep the cars momentum going.
This car was actually a v6 but it does have power brakes. How much weight do you think it would save? I am also ditching the power steering for a manual steering rack.
I've got a 3.23 in mine now, that will be swapped out for a 3.73 this weekend. When I replaced my stock front brakes with Wilwood 12.19" Dynalites, the car probably lost 20 pounds of unsprung weight off each corner. BIG difference in handling.
Without me in it, the car weighs around 2950 (factory non-AC with considerable weight reduction). Stock weight was 3465.
One bit of advice: don't ditch the factory PS box without doing some research. A "performance" factory PS box is 10:1 (2.5 steering wheel turns, lock to lock). The best bolt-in manual box will be something like 18:1 and most are 24:1 - you'll feel like steering an ocean liner. This is fine for drag racing, but if you'd like to take corners without having to plan way in advance, you might think twice about this.
07-19-2012, 11:04 AM
#38
On The Tree
Thread Starter
At least yours is all one color
I've got a 3.23 in mine now, that will be swapped out for a 3.73 this weekend. When I replaced my stock front brakes with Wilwood 12.19" Dynalites, the car probably lost 20 pounds of unsprung weight off each corner. BIG difference in handling.
Without me in it, the car weighs around 2950 (factory non-AC with considerable weight reduction). Stock weight was 3465.
One bit of advice: don't ditch the factory PS box without doing some research. A "performance" factory PS box is 10:1 (2.5 steering wheel turns, lock to lock). The best bolt-in manual box will be something like 18:1 and most are 24:1 - you'll feel like steering an ocean liner. This is fine for drag racing, but if you'd like to take corners without having to plan way in advance, you might think twice about this.
I've got a 3.23 in mine now, that will be swapped out for a 3.73 this weekend. When I replaced my stock front brakes with Wilwood 12.19" Dynalites, the car probably lost 20 pounds of unsprung weight off each corner. BIG difference in handling.
Without me in it, the car weighs around 2950 (factory non-AC with considerable weight reduction). Stock weight was 3465.
One bit of advice: don't ditch the factory PS box without doing some research. A "performance" factory PS box is 10:1 (2.5 steering wheel turns, lock to lock). The best bolt-in manual box will be something like 18:1 and most are 24:1 - you'll feel like steering an ocean liner. This is fine for drag racing, but if you'd like to take corners without having to plan way in advance, you might think twice about this.
I actually just weighed mine a few weeks ago. 3300 with out me in it. I did remove the factory A/C and the stock fuel tank for a 12 gal fuel cell.
It has power steering now but the belt never stays on. I know you look real funny pulling into a parking spot turning your wheel 3 or 4 times. The car will be used for drag racing and Sunday drives.
07-19-2012, 01:18 PM
#39
TECH Fanatic
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I gotta get me one of those. You guys with the late '70s birds can go which ever way you want with them, and I love how they look when brought back up and finished paint. I would love to have a black one with the gold rims (gold edition-I think?) and drop an LS powerplant in her. I'd do the phoenix in gold but ghosted on, and some dark DARK purple/plum added to the black. Either way nice cars (even the one with the mismatched colors 
) and great runs. Thanks for posting, it was nice to see something different.
) and great runs. Thanks for posting, it was nice to see something different.
07-20-2012, 11:40 AM
#40
Tossing the power brakes only saves a couple pounds, but it enables you to clean up the engine bay and also not require a vacuum canister to keep brake pressure up. I'd personally go that route again in a heartbeat.
I also had manual steering but damn that was hard work with any kind of normal sized tire on the front. So I installed the close ratio power steering rack out of an '81 Z28 (1980 and up Z28's had the much sought after close ratio) Personally I'd say thats only viable when you are running a big n little setup where the tiny front tire has less resistance to low speed turning.
I also had manual steering but damn that was hard work with any kind of normal sized tire on the front. So I installed the close ratio power steering rack out of an '81 Z28 (1980 and up Z28's had the much sought after close ratio) Personally I'd say thats only viable when you are running a big n little setup where the tiny front tire has less resistance to low speed turning.
aluminum front bumper and mounts (saved 40 pounds)
plastic/aluminum radiator (saved 15 pounds)
LS1 replacing SB 305 (saved 125 pounds)
T56 + light flywheel and clutch replacing TH350 and TQ converter (50 pounds)
Wilwood Dynalite front brakes (40 pounds, unsprung)
Aluminum drive shaft (20 pounds)
Wilwood manual brake master cylinder (10 pounds)
LTH + new exhaust (30 pounds)
Fiberglass hood and trunk lid (100 pounds)
Lexan glass all around (50 pounds)
Corbeau fixed back racing seats (30 pounds)
