Burning rubber
Thread Starter
Cruising
Joined: Jul 2015
Posts: 14
Likes: 0
This is what I found on that cam.
http://usaperform.com/street-fighter...ift-p-497.html
That's an old school grind. Low intensity ramps on those lobes. This means that the valves are open longer but not in a useful way.
Your over lap (time both intake and exhaust valves are open) is 71*. This is probably pared with a late intake closing. All boils down to less torque off idle but higher RPM capability.
The valve lift is normal for a flat tappet, but low compared to a roller cam. You will make power but it's gonna be later on. Maybe 2500-3000 +RPM range. A stall converter would definitely help here. Your stock 1800ish stall converter makes it a dog off the bottom.
That or different gearing.
Or....a different cam. Hmm. Depends on your mechanical aptitude.
http://usaperform.com/street-fighter...ift-p-497.html
That's an old school grind. Low intensity ramps on those lobes. This means that the valves are open longer but not in a useful way.
Your over lap (time both intake and exhaust valves are open) is 71*. This is probably pared with a late intake closing. All boils down to less torque off idle but higher RPM capability.
The valve lift is normal for a flat tappet, but low compared to a roller cam. You will make power but it's gonna be later on. Maybe 2500-3000 +RPM range. A stall converter would definitely help here. Your stock 1800ish stall converter makes it a dog off the bottom.
That or different gearing.
Or....a different cam. Hmm. Depends on your mechanical aptitude.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
Thread Starter
Cruising
Joined: Jul 2015
Posts: 14
Likes: 0
This is what I found on that cam.
http://usaperform.com/street-fighter...ift-p-497.html
That's an old school grind. Low intensity ramps on those lobes. This means that the valves are open longer but not in a useful way.
Your over lap (time both intake and exhaust valves are open) is 71*. This is probably pared with a late intake closing. All boils down to less torque off idle but higher RPM capability.
The valve lift is normal for a flat tappet, but low compared to a roller cam. You will make power but it's gonna be later on. Maybe 2500-3000 +RPM range. A stall converter would definitely help here. Your stock 1800ish stall converter makes it a dog off the bottom.
That or different gearing.
Or....a different cam. Hmm. Depends on your mechanical aptitude.
http://usaperform.com/street-fighter...ift-p-497.html
That's an old school grind. Low intensity ramps on those lobes. This means that the valves are open longer but not in a useful way.
Your over lap (time both intake and exhaust valves are open) is 71*. This is probably pared with a late intake closing. All boils down to less torque off idle but higher RPM capability.
The valve lift is normal for a flat tappet, but low compared to a roller cam. You will make power but it's gonna be later on. Maybe 2500-3000 +RPM range. A stall converter would definitely help here. Your stock 1800ish stall converter makes it a dog off the bottom.
That or different gearing.
Or....a different cam. Hmm. Depends on your mechanical aptitude.
Thread Starter
Cruising
Joined: Jul 2015
Posts: 14
Likes: 0
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
Longtubes will get you some low end and SOP. 2-1/4 would work fine with shorties and I'd go 2-1/2 with longtubes. http://www.exhaustvideos.com/faq/how...pipe-diameter/
What kind of intake? Dual plane would get you some low end or at least adding a 4 hole spacer will help.
Plenty of ways to achieve the same results, heck you could even go to a smaller tire. What size do you have?
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
Things to consider using a stall converter is the increased heat of using one. I have a 2600 stall and use an additional transmission cooler mounted up front to provide additional cooling for the transmission. Heat is the killer of the trans.
Torque converter manufacturers can give you a decent recommendation for the stall you might need based on your specs and the kind of driving you do. If I were to guess I would say around 2800 RPM with that 3.08. Maybe 2500 with a 3.55.
As augie pointed out your RPMs at cruise will rise with the use of a lower ratio gear in the back and the TH350. This calculator can help in guessing how much.
http://www.crawlpedia.com/rpm_gear_calculator.htm
If I put in my specs with 27 inch tires it tells me 2500 RPM at 65 MPH. I know from my own observation that it is more like 2700 RPM. So an auto has slippage via that torque converter.
Good torque converters will not have much slippage 2-3% at stall. Cheaper ones have more slippage and may be less durable. I would hesitate to get the cheap ones offered by on line dealers that do not build those converters. A fragged converter takes the transmission with it.
Keep in mind that an advertised stall of 2500 may vary depending on the torque developed by your engine at that RPM. My torque converter was advertised as a 2200 stall. After rebuilding the engine it stalls at 2600 due to the increased torque to the converter. This is where places that can build your toque converter can help out a lot. Some even offer to adjust your stall for free if it's not what they said it would be.
Torque converter manufacturers can give you a decent recommendation for the stall you might need based on your specs and the kind of driving you do. If I were to guess I would say around 2800 RPM with that 3.08. Maybe 2500 with a 3.55.
As augie pointed out your RPMs at cruise will rise with the use of a lower ratio gear in the back and the TH350. This calculator can help in guessing how much.
http://www.crawlpedia.com/rpm_gear_calculator.htm
If I put in my specs with 27 inch tires it tells me 2500 RPM at 65 MPH. I know from my own observation that it is more like 2700 RPM. So an auto has slippage via that torque converter.
Good torque converters will not have much slippage 2-3% at stall. Cheaper ones have more slippage and may be less durable. I would hesitate to get the cheap ones offered by on line dealers that do not build those converters. A fragged converter takes the transmission with it.
Keep in mind that an advertised stall of 2500 may vary depending on the torque developed by your engine at that RPM. My torque converter was advertised as a 2200 stall. After rebuilding the engine it stalls at 2600 due to the increased torque to the converter. This is where places that can build your toque converter can help out a lot. Some even offer to adjust your stall for free if it's not what they said it would be.
Last edited by REELAV8R; Jul 23, 2015 at 11:31 AM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
Corvettes hook pretty fair with the independent rear, but you should still be able to spin the tires. If the stall doesn't match up to the power range it won't want to spin. Remember spinning isn't winning though.