I definitely liked it better than the TH350, but I wanted a manual and the 700R4 is not a manual.
L82 upgrade thread
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Melting Slicks
Joined: Oct 2011
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From: Sacramento California
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Advanced the timing to 16 initial, 32 with mechanical. Runs 32 degrees at idle with manifold vac on the advance can.
Really woke the car up 4 degrees....wow
Do I need to re adjust the mixture screws after adjusting the idle speed and advance?
Really woke the car up 4 degrees....wow
Do I need to re adjust the mixture screws after adjusting the idle speed and advance?
Last edited by DucatiDon; Mar 26, 2013 at 11:23 PM.
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St. Jude Donor '08-'09
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From: San Jose CA
Yes, you should. Especially the idle speed; you'll be using more(or less) of the transition slot.
Le Mans Master
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From: Las Vegas - Just stop perpetuating myths please.
Nothing wrong with the 5spd but it is alot more work converting and alot more $$$. While the 700R4 has a steep 1st gear with an overdrive - should be just as much fun to drive - even daily.
Good luck,
cardo0
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About 30 years ago I first heard a guy say that and I couldn't figure out what he was talking about. It wasn't until recently when I saw it written I realized why I couldn't understand him, I thought he was saying "rape dape". I thought "What's a rape dape? I don't get it."
Thread Starter
Melting Slicks
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From: Sacramento California
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Did I mention that I have 3.90 gears? Ugh. Gas guzzler!
But fun to launch!
Really need an od next.....
But fun to launch!
Really need an od next.....
Le Mans Master
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From: Saskatoon Saskatchewan
Don, what size motor do you have in your 63 and how much hp do you think its putting out? Reason I ask is I've got an RS400 waiting to go in my 79, it has 3.70 gears and I'm planning modifying the motor to put out 325-350 hp and I'm wondering how much tire spin I'll get and If I can get it to launch decently.
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Melting Slicks
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From: Sacramento California
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my 63 has the stock 340hp 327 with a slightly bigger solid cam. I dont know if its been bored or not. Its possible, Ive never had the heads off....yet.
Id guess the 63 327 makes less than my 350 in the 78, although it revs much quicker over 3k. With that combo, you will get a lot of spin.
If I was drag racing, Id like a slightly taller 1st than what the RS500 has...as folks have mentioned. As it is for cruising its fine. Keeps the rpm up so it doesnt bog, while going real slow in traffic or cruising...
For the 78 I will definitely want a taller first, due to the 3.90s. (or change the gears)
Id guess the 63 327 makes less than my 350 in the 78, although it revs much quicker over 3k. With that combo, you will get a lot of spin.
If I was drag racing, Id like a slightly taller 1st than what the RS500 has...as folks have mentioned. As it is for cruising its fine. Keeps the rpm up so it doesnt bog, while going real slow in traffic or cruising...
For the 78 I will definitely want a taller first, due to the 3.90s. (or change the gears)
Le Mans Master
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From: Saskatoon Saskatchewan
That sounds nice. I find with my 3.70 rear and close ratio four speed I have to rev the motor fairly high and ride the clutch more than I like to get it moving and it won't drive slow enough in 1st with the clutch out for my tastes.
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Melting Slicks
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Did I mention that my advance is all in by 1700? I think the mech advance may be sticking causing a slight hesitation. Im considering a new distributor....
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Have you pulled the weights to see if they're corroded or anything like that?
Thread Starter
Melting Slicks
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Recent update....
Didnt like the lazy throttle response and boiling fuel, so i ordered a 4 hole gasket and heat shield.
Pulled the carb off, and the shop had installed an open gasket.
I replaced that with a 4 hole gasket and a steel insulator plate.
AMAZING what a difference a gasket can make!
Car is much more fun to drive and has immensely better throttle response.
Carb fuel is a little cooler too!
Didnt like the lazy throttle response and boiling fuel, so i ordered a 4 hole gasket and heat shield.
Pulled the carb off, and the shop had installed an open gasket.
I replaced that with a 4 hole gasket and a steel insulator plate.
AMAZING what a difference a gasket can make!
Car is much more fun to drive and has immensely better throttle response.
Carb fuel is a little cooler too!
Le Mans Master
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From: RI, Now Franklin/Nashville TN
Don,
Are you going to get it on the dyno again since you have fine tuned the L-82 and rev it to at least 6,000 RPM? I would like to see the real potential of the L-82 with your changes. Below is my best dyno run with my mostly stock L-82-only changes are a 4175 Holley 650 CFM Q-jet replacement, comp cams roller TIPPED 1.5 rockers, no emissions, 2.5 duals with Monze Turbo Mufflers, McJacks, and K&N air cleaner in stock dual snorkel housing-everything else is original GM internally to the engine including big valve 882 heads and L-82 cam. Best RWHP was 233! I also have a weak #6 cylinder compression which I think is from a leaky valve. Motor has 66,000 miles on it. I was thinking that you should be somewhere around 300 RWHP with your combo compared to my stock 233 RWHP.
[IMG]
[/IMG]
http://s894.photobucket.com/user/jba...01781.mp4.html
Are you going to get it on the dyno again since you have fine tuned the L-82 and rev it to at least 6,000 RPM? I would like to see the real potential of the L-82 with your changes. Below is my best dyno run with my mostly stock L-82-only changes are a 4175 Holley 650 CFM Q-jet replacement, comp cams roller TIPPED 1.5 rockers, no emissions, 2.5 duals with Monze Turbo Mufflers, McJacks, and K&N air cleaner in stock dual snorkel housing-everything else is original GM internally to the engine including big valve 882 heads and L-82 cam. Best RWHP was 233! I also have a weak #6 cylinder compression which I think is from a leaky valve. Motor has 66,000 miles on it. I was thinking that you should be somewhere around 300 RWHP with your combo compared to my stock 233 RWHP.
[IMG]
[/IMG]http://s894.photobucket.com/user/jba...01781.mp4.html
Last edited by jb78L-82; May 19, 2013 at 06:17 AM.
Thread Starter
Melting Slicks
Joined: Oct 2011
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From: Sacramento California
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It looks like I have about a 30 hp gain over yours across the range.
Id like to get it back on the dyno this spring, when I do Ill post the results.
I dont know if the few tweaks Ive made will translate to dyno HP, but by the seat of the pants, its a huge improvement.
As far as comparisons go:
4175 Holley 650 CFM Q-jet replacement, vs Edelbrock AVS 650
comp cams roller TIPPED 1.5 rockers, vs Scorpion Full Roller 1.5
no emissions, vs full emissions. (OK, EGR is disconnected, and AIR injection is inoperable awaiting diverter valve rebuild)
2.5 duals with Monze Turbo Mufflers, vs 2.5 duals with Magnaflows and Dual Cats.
McJacks, vs McJacks
K&N air cleaner in stock dual snorkel housing vs Open element Spectre air cleaner.
Stock L82 cam vs Howards full hydraulic roller .500/.510 230@ .050
Stock L82 intake vs Performer RPM.
Stock 882 heads vs AFR 195cc 2.05/1.60 with thin head gasket. (10.25 compression)
???? vs 3.70 Posi
??? vs stock Turbo 350 Auto
Best RWHP was 233! vs ??
220 hp @ 4500 vs 245 @ 4500
I also expect some disparity between dyno's...never get the same numbers from different runs on different dynos. But the curves look about right.
Id like to see at least 300 at the wheel....It certainly looks doable.
Id like to get it back on the dyno this spring, when I do Ill post the results.
I dont know if the few tweaks Ive made will translate to dyno HP, but by the seat of the pants, its a huge improvement.
As far as comparisons go:
4175 Holley 650 CFM Q-jet replacement, vs Edelbrock AVS 650
comp cams roller TIPPED 1.5 rockers, vs Scorpion Full Roller 1.5
no emissions, vs full emissions. (OK, EGR is disconnected, and AIR injection is inoperable awaiting diverter valve rebuild)
2.5 duals with Monze Turbo Mufflers, vs 2.5 duals with Magnaflows and Dual Cats.
McJacks, vs McJacks
K&N air cleaner in stock dual snorkel housing vs Open element Spectre air cleaner.
Stock L82 cam vs Howards full hydraulic roller .500/.510 230@ .050
Stock L82 intake vs Performer RPM.
Stock 882 heads vs AFR 195cc 2.05/1.60 with thin head gasket. (10.25 compression)
???? vs 3.70 Posi
??? vs stock Turbo 350 Auto
Best RWHP was 233! vs ??
220 hp @ 4500 vs 245 @ 4500
I also expect some disparity between dyno's...never get the same numbers from different runs on different dynos. But the curves look about right.
Id like to see at least 300 at the wheel....It certainly looks doable.