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It’s time to formalize the challenge: Let’s get the 03 and 04 SSRs from a 0 to 60 time of 7.6 sec (average weight driver, couple gallons of fuel) under 6 seconds, into the high 5s.
Don’t laugh. My own 04 SSR is 2/3, or more, of the way there as I write this.
A stock 03 or 04 SSR with a 160 lb driver and 2 gallons of fuel can, according to Chevrolet, and actual road tests, do the 0 to 60 in about 7.6 seconds. I weigh more than 160 lb (!) and I don’t run around, or do acceleration testing, with only a couple of gallons of fuel, but rather I test with 14 to 15 gallons since that is more typical of the fuel weight load I normally have aboard. Bone stock, my computer modeling software says that I should run 0 to 60 in about 8.1 seconds.
I have done just 3 things to improve my 0 to 60 times so far:
- Changed the rear axle ratio from 3.73 to 4.56
- Had the SSR tuned after the change using a Dynojet dyno and HP Tuner
- Started shifting the automatic transmission manually on testing runs, shifting at 6000 rpm instead of letting it shift automatically at the factory setting of 5600 (I will get this programmed into the ECU via HP Tuner at my local speed shop in the next few days)
Shortly after doing the gear ratio change, I acquired a G-Tech RR computerized vehicle accelerometer that comes with software that installs on your home computer and provides amazingly detailed data on each and every test run you make. My current results as measured by the G-Tech, with my driver weight of 235 lb and 15 gallons of fuel aboard are 0 to 60 in 6.5 seconds. So I am 2/3 of the way towards the 5s – without getting mechanically inside the engine!! And, remember that that is with me and a bunch of fuel aboard.
I got these results for a total expenditure of about $1500, by using an analytical versus “my buddy says” or “experience says” or “that’ll never work” approach. I analyzed the power curve of the 5.3 liter SSR engine, looked very closely at the transmission gearing, and applied a lot of what I have learned doing similar projects on fast motorcycles (10 second ¼ mile machines with 0 to 60 in well under 3 seconds).
Why do this to a heavyweight (4639 lb) cruiser? Because most hotrodders and all of the auto enthusiast media have made a big mistake in writing off the 5.3Liter SSRs as being incapable of nimble performance. Ironically, this has contributed to the difficulty in selling new leftover SSRs despite attractive pricing, because although GM built a “cruiser”, their advertising, and the styling of the vehicle itself, both imply “hot rod”. I am now certain that I can prove the doubters wrong, and in fact, if I am right, some enterprising dealer or speed shop should buy up all those leftover new 04s, apply some of the the same mods that I have done and will do, and sell them as fairly unique performance vehicles!
My computer modeling software says that to hit the high 5s, I need about 10% more average power being applied than I’ve got right now..
To figure out how to GET that power, it’s time to get even more scientific.
Below is a screen captured from my G-Tech’s PASS software. Note the current “baseline” results achieved early last Sunday morning at that secret straight and level test site which was retroactively discovered to be within a fraction of a mile of a police station (see my recent “I THOUGHT I was alone” posting).
(see image attached below. It IS fully readable if you PRINT it!)
This screen shot displays one of many graphs available in this software: the RPM versus time, for a complete ¼ mile run (and slightly beyond).
This graph has acquired new significance for me since I finished reading John Lingenfelter’s book on building Chevy engines. He shows early in that book how this graph can show you pretty precisely what rpm range to focus your improvement efforts upon. Lingenfelter’s advice is to look at what rpm range your engine is spending most of its time during the run, and optimize the power in that range.
Notice how I have dropped vertical lines onto the graph. These lines divide the entire 1/4 mile run into rpm ranges:
Under 4000 rpm (labeled “<4k” on the graph)
4000 to 5000 rpm (labeled “4k-5k”)
5000 to 6000 rpm (and slightly above 6000) (labeled 5k-6k)
It is VERY interesting to look at how much of the 15.07 seconds of the ¼ mile run were spent in each rpm range:
Under 4000 rpm: 1.6 sec or 11%
4000 – 5000 rpm: 8.0 sec or 53%
5000 – 6000 rpm: 4.1 sec or 27%
Shifting & flywheel / torque converter effects: 1.3 sec or 9%
For the 0 to 60 time (instead of the ¼ mile time breakdown shown above):
Under 4000 rpm: 1.6 sec or 25%
4000 – 5000 rpm: 2.4 sec or 37%
5000 – 6000 rpm: 1.7 sec or 26%
Shifting & flywheel / torque converter effects: 0.8 sec or 12%
Makes it pretty obvious where the efforts on getting more power should be concentrated, doesn’t it? The 4000 to 5000 rpm range should be the priority target, with 2nd priority going to 5000 to 6000 rpm. Spending a lot of time and money on the rpm range below 4000 rpm is not going to help the effort much, since even a 25% increase in power there is going to change the time by only 0.4 sec or thereabouts, which is not enough to get into the 5s, AND:
1. Torque converter effects help us at 2000 rpm or below anyway, and
2. We can achieve MORE time reduction with LESS percentage power improvement in the rpm ranges where most of time is being spent.
Remember, the modeling software says the required power increase to hit high 5s is an AVERAGE of only 10% across the rpm range, and that that power increase would also get us to about 14.7 seconds in the ¼ mile.
As an aside before anyone with a stock SSR gets too excited, remember that the above rpm versus time analysis applies to MY SSR which has been significantly regeared (22.2%!). The time slices are going to be entirely different for a stock SSR, as that crippling stock gearing will drag out the “under 4000 rpm” time slice a LOT, at the expense of mostly the 5000 to 6000 rpm time slices, and a shift at 5600 rpm into 2nd is going to drop the engine way down to 3000 rpm, where it will struggle some more. You’ll need to do your own, different analysis for a stock or differently modified SSR.
BUT, getting back to MY mission to find another 10% average power increase beyond what I have already gotten, very few power increasing methods work that uniformly across the ENTIRE rpm range. A positive displacement screw type engine driven supercharger has that kind of capability (and much greater actually – more like 40% more power!), and is on a dollar per horsepower basis the best “value”, BUT it requires investing ALL the money to do it in one chunk. With a son in college, and too many involuntary simultaneous residences in 3 states right now, coming up with one big chunk like that is not a great idea for me. And vendors don’t offer “easy terms”!
What I AM thinking is some combination of:
- Cold air intake
- Cat-back exhaust
- Headers
- Hi-flow cats
I’m pretty sure that I need some “combination” because no one of these has the potential to make a 10% across the rpm range improvement by itself, despite vendor claims and so-called dyno charts that sometimes imply otherwise.
My need now is very straightforward: I need REAL and RELIABLE “before and after” dyno curves for vehicles with SIMILAR initial states of tune as my SSR has as its starting point. By that, I mean I do NOT want dyno curves that show how a set of headers uncorked an engine and added 40 hp, when the underlying truth is that everything ELSE except headers had been done, and so the exhaust manifold became a “bottleneck” that was preventing the other mods from being fully effective, and so the apparent effect of the headers didn’t just show the results of the headers but rather of ALL the mods!
I am thinking that there are probably a few of you out there who have the same itch as I do here, and so maybe if we all make a concerted effort to find GOOD reports and dyno curves, that describe accurately the effects of ONE of the above potential mods in reasonable isolation, on an engine reasonably similar to our 5.3 liter LM4 engines, we might be able to get to the high5s with a lot less time and money being spent and wasted.
Also, any of you vendors out there monitoring our board: If you have a product that you can back up with a solid guarantee of performance to at least a specified level, let me hear from you. As you can see from the above action and results, I am not just messing around.
So, anyone out there got any solid information they can contribute to this challenge project?
Jim G
[email protected]
Don’t laugh. My own 04 SSR is 2/3, or more, of the way there as I write this.
A stock 03 or 04 SSR with a 160 lb driver and 2 gallons of fuel can, according to Chevrolet, and actual road tests, do the 0 to 60 in about 7.6 seconds. I weigh more than 160 lb (!) and I don’t run around, or do acceleration testing, with only a couple of gallons of fuel, but rather I test with 14 to 15 gallons since that is more typical of the fuel weight load I normally have aboard. Bone stock, my computer modeling software says that I should run 0 to 60 in about 8.1 seconds.
I have done just 3 things to improve my 0 to 60 times so far:
- Changed the rear axle ratio from 3.73 to 4.56
- Had the SSR tuned after the change using a Dynojet dyno and HP Tuner
- Started shifting the automatic transmission manually on testing runs, shifting at 6000 rpm instead of letting it shift automatically at the factory setting of 5600 (I will get this programmed into the ECU via HP Tuner at my local speed shop in the next few days)
Shortly after doing the gear ratio change, I acquired a G-Tech RR computerized vehicle accelerometer that comes with software that installs on your home computer and provides amazingly detailed data on each and every test run you make. My current results as measured by the G-Tech, with my driver weight of 235 lb and 15 gallons of fuel aboard are 0 to 60 in 6.5 seconds. So I am 2/3 of the way towards the 5s – without getting mechanically inside the engine!! And, remember that that is with me and a bunch of fuel aboard.
I got these results for a total expenditure of about $1500, by using an analytical versus “my buddy says” or “experience says” or “that’ll never work” approach. I analyzed the power curve of the 5.3 liter SSR engine, looked very closely at the transmission gearing, and applied a lot of what I have learned doing similar projects on fast motorcycles (10 second ¼ mile machines with 0 to 60 in well under 3 seconds).
Why do this to a heavyweight (4639 lb) cruiser? Because most hotrodders and all of the auto enthusiast media have made a big mistake in writing off the 5.3Liter SSRs as being incapable of nimble performance. Ironically, this has contributed to the difficulty in selling new leftover SSRs despite attractive pricing, because although GM built a “cruiser”, their advertising, and the styling of the vehicle itself, both imply “hot rod”. I am now certain that I can prove the doubters wrong, and in fact, if I am right, some enterprising dealer or speed shop should buy up all those leftover new 04s, apply some of the the same mods that I have done and will do, and sell them as fairly unique performance vehicles!
My computer modeling software says that to hit the high 5s, I need about 10% more average power being applied than I’ve got right now..
To figure out how to GET that power, it’s time to get even more scientific.
Below is a screen captured from my G-Tech’s PASS software. Note the current “baseline” results achieved early last Sunday morning at that secret straight and level test site which was retroactively discovered to be within a fraction of a mile of a police station (see my recent “I THOUGHT I was alone” posting).
(see image attached below. It IS fully readable if you PRINT it!)
This screen shot displays one of many graphs available in this software: the RPM versus time, for a complete ¼ mile run (and slightly beyond).
This graph has acquired new significance for me since I finished reading John Lingenfelter’s book on building Chevy engines. He shows early in that book how this graph can show you pretty precisely what rpm range to focus your improvement efforts upon. Lingenfelter’s advice is to look at what rpm range your engine is spending most of its time during the run, and optimize the power in that range.
Notice how I have dropped vertical lines onto the graph. These lines divide the entire 1/4 mile run into rpm ranges:
Under 4000 rpm (labeled “<4k” on the graph)
4000 to 5000 rpm (labeled “4k-5k”)
5000 to 6000 rpm (and slightly above 6000) (labeled 5k-6k)
It is VERY interesting to look at how much of the 15.07 seconds of the ¼ mile run were spent in each rpm range:
Under 4000 rpm: 1.6 sec or 11%
4000 – 5000 rpm: 8.0 sec or 53%
5000 – 6000 rpm: 4.1 sec or 27%
Shifting & flywheel / torque converter effects: 1.3 sec or 9%
For the 0 to 60 time (instead of the ¼ mile time breakdown shown above):
Under 4000 rpm: 1.6 sec or 25%
4000 – 5000 rpm: 2.4 sec or 37%
5000 – 6000 rpm: 1.7 sec or 26%
Shifting & flywheel / torque converter effects: 0.8 sec or 12%
Makes it pretty obvious where the efforts on getting more power should be concentrated, doesn’t it? The 4000 to 5000 rpm range should be the priority target, with 2nd priority going to 5000 to 6000 rpm. Spending a lot of time and money on the rpm range below 4000 rpm is not going to help the effort much, since even a 25% increase in power there is going to change the time by only 0.4 sec or thereabouts, which is not enough to get into the 5s, AND:
1. Torque converter effects help us at 2000 rpm or below anyway, and
2. We can achieve MORE time reduction with LESS percentage power improvement in the rpm ranges where most of time is being spent.
Remember, the modeling software says the required power increase to hit high 5s is an AVERAGE of only 10% across the rpm range, and that that power increase would also get us to about 14.7 seconds in the ¼ mile.
As an aside before anyone with a stock SSR gets too excited, remember that the above rpm versus time analysis applies to MY SSR which has been significantly regeared (22.2%!). The time slices are going to be entirely different for a stock SSR, as that crippling stock gearing will drag out the “under 4000 rpm” time slice a LOT, at the expense of mostly the 5000 to 6000 rpm time slices, and a shift at 5600 rpm into 2nd is going to drop the engine way down to 3000 rpm, where it will struggle some more. You’ll need to do your own, different analysis for a stock or differently modified SSR.
BUT, getting back to MY mission to find another 10% average power increase beyond what I have already gotten, very few power increasing methods work that uniformly across the ENTIRE rpm range. A positive displacement screw type engine driven supercharger has that kind of capability (and much greater actually – more like 40% more power!), and is on a dollar per horsepower basis the best “value”, BUT it requires investing ALL the money to do it in one chunk. With a son in college, and too many involuntary simultaneous residences in 3 states right now, coming up with one big chunk like that is not a great idea for me. And vendors don’t offer “easy terms”!
What I AM thinking is some combination of:
- Cold air intake
- Cat-back exhaust
- Headers
- Hi-flow cats
I’m pretty sure that I need some “combination” because no one of these has the potential to make a 10% across the rpm range improvement by itself, despite vendor claims and so-called dyno charts that sometimes imply otherwise.
My need now is very straightforward: I need REAL and RELIABLE “before and after” dyno curves for vehicles with SIMILAR initial states of tune as my SSR has as its starting point. By that, I mean I do NOT want dyno curves that show how a set of headers uncorked an engine and added 40 hp, when the underlying truth is that everything ELSE except headers had been done, and so the exhaust manifold became a “bottleneck” that was preventing the other mods from being fully effective, and so the apparent effect of the headers didn’t just show the results of the headers but rather of ALL the mods!
I am thinking that there are probably a few of you out there who have the same itch as I do here, and so maybe if we all make a concerted effort to find GOOD reports and dyno curves, that describe accurately the effects of ONE of the above potential mods in reasonable isolation, on an engine reasonably similar to our 5.3 liter LM4 engines, we might be able to get to the high5s with a lot less time and money being spent and wasted.
Also, any of you vendors out there monitoring our board: If you have a product that you can back up with a solid guarantee of performance to at least a specified level, let me hear from you. As you can see from the above action and results, I am not just messing around.
So, anyone out there got any solid information they can contribute to this challenge project?
Jim G
[email protected]
