LS road race/autox Motor choices
#61
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So it looks like I'm only looking at about another $1000 to build a 408 vs the 366. Seems kinda silly to leave that type of power difference on the table if we are only talking 1K difference.
What do you guys think? Based on my calculations the 366 would make around 485rwhp/439rwtq whereas the 408 would make 540rwhp/488rwtq.
Those are pretty big differences for just 1k. Plus I could run a less aggressive cam, so we potentially have more longevity with this setup due to being not as hard on valvetrain parts.
I am all for "learning to drive" with a nearly stock hp level car, then as you progress as a driver moving up to something that makes better power. But in this situation, the cost to remove/rebuild the stock cube LS2 after a couple years, to move to the 408, just seems like a waste. It would be way more costly to R&R that vs the 1K difference to build the 408 to begin with.
Am I stupid for looking at it this way?
What do you guys think? Based on my calculations the 366 would make around 485rwhp/439rwtq whereas the 408 would make 540rwhp/488rwtq.
Those are pretty big differences for just 1k. Plus I could run a less aggressive cam, so we potentially have more longevity with this setup due to being not as hard on valvetrain parts.
I am all for "learning to drive" with a nearly stock hp level car, then as you progress as a driver moving up to something that makes better power. But in this situation, the cost to remove/rebuild the stock cube LS2 after a couple years, to move to the 408, just seems like a waste. It would be way more costly to R&R that vs the 1K difference to build the 408 to begin with.
Am I stupid for looking at it this way?
The drag racer mentality is STRONG in this one.
Save the $1000 and buy you some brakes, ducting, and sheet metal spindle ducts from Blaine Fabrication.
Watch this vid, and understand WHY 540 to the wheels won't help you. The only thing a lot of power teaches you is to WAIT on the next straight to play catch up and set your brakes on fire.
This is at NOLA Motorsports Park in La, my first time at this track. This track is VERY slick. Pay particular attention from 9:55 on, thats when school starts.
At the end of day 2 I could pass the Miata, but was still very very close.
http://youtu.be/q0qkpqNwLvM
Last edited by FASTFATBOY; 07-15-2012 at 08:40 PM.
#62
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Geebus, some of the **** you see posted on the internet puked up by someone who read it somewhere.
RPM KILLS engines. The end.
In a autox or HPDE car you want tabletop flat TORQUE.
Most autox events in our cars should be run in 2nd gear.
I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.
The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.
Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.
IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.
Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.
If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.
This was my first weekend at this track.
http://youtu.be/qCNDermGiwg
RPM KILLS engines. The end.
In a autox or HPDE car you want tabletop flat TORQUE.
Most autox events in our cars should be run in 2nd gear.
I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.
The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.
Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.
IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.
Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.
If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.
This was my first weekend at this track.
http://youtu.be/qCNDermGiwg
FWIW, my motor we are building is going to peak around 6300, I plan on using the IR baffle, and potentially an accusump to control oil, the use of LS2 was because that is what we had available (spare LS2 block from spun rod bearing in TBSS). While more HP is certainly not needed on autox, since I was going to have to build a motor I opted to go a little bigger (408ci), and have a broader powerband (so I wouldn't have to lean on it as much to make power). I'm sure it will be way more power that I need for my limited driving skills, but hopefully I can "grow" into the power with practice. On the bigger courses during HPDE/road course events, the power of the 408 should be useful.
#63
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Ouch. Lets keep the comments on track. I have an extra grand to put towards the build, AND still have aftermarket brakes, blain fab ducts etc. This car is NOT going to be just a track car. It will see significant street duty as well. I don't drag race. I feel like my rationale is justified in doing the bigger motor. Cost/benefit favors it. To say that more power is harmful may be true in my hands, but a properly setup car in hands of someone who CAN drive wins. Sure tight courses it won't reallly help, and could actually be a detriment on Autox, but its the decision I'm sticking with.
How did you like the NT05's in your application?
How did you like the NT05's in your application?
#64
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Ouch. Lets keep the comments on track. I have an extra grand to put towards the build, AND still have aftermarket brakes, blain fab ducts etc. This car is NOT going to be just a track car. It will see significant street duty as well. I don't drag race. I feel like my rationale is justified in doing the bigger motor. Cost/benefit favors it. To say that more power is harmful may be true in my hands, but a properly setup car in hands of someone who CAN drive wins. Sure tight courses it won't reallly help, and could actually be a detriment on Autox, but its the decision I'm sticking with.
How did you like the NT05's in your application?
How did you like the NT05's in your application?
I can tell you this, the guy in the second video that passed me on the first lap in the black F body had a head cam deal that made 460rwhp and weighed 3300 ready to race.
His power to weight will be similar to yours EXCEPT, your brakes are gonna FRY with that much power. His C6 Brakes with ducts and hoses would KILL brake pads, a $250 set of fronts would do good to last 1 or 1.5 events. With that said, put 18 inch wheels on and buy the biggest brakes that will fit inside them.
He drove my car the last session of the day, went home and took his engine apart to make it a LS6 like I have, he saw the light. Instead of buying 18 inch wheels and the more expensive tires to go with them JUST to put bigger brakes on the car he decided to pull some power out of it and DRIVE the car better.
IMO the NT-05 is THE best tire for the money out there, grip is good and they last very well on track.
A word of advice, don't get on sticky tires for a while, stay on cheap street tires for at least 4-5 trackday events(8-10 days) before even moving up to a NT-05.
HPDE is not racing, it's learning how to drive and do it well. The F Body platform can be setup to handle very well, the weight is the killer.
#65
If Miatas are anything more than a rolling chicane, you don't give advice.
#66
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The last set of corners at NOLA I couldn't figure out, he pulled out a lot of ground in that section.
To put that into perspective, my car runs 115mph in the 1/4 mile. Spec Miata's make maybe 150 rwhp.
Again, the typical drag racer mentality. Road course racing is about grip and corner speed. I was trying to point out with my 385 rwhp car with a lot of suspension and a decent driver has a hard time dealing with a 4 cylinder car on slicks. It's all about momentum and learning how to keep it, not about having a lot of power to go fast.
Do you road course race?
EDIT
I just realized you are the OP.
You are in for a RUDE awakening when you get on track with all that power and you have to point a Spec Miata by and watch him LEAVE you, all of the things I said will come into clarity.
Most all of us who came from the drag racing world have this kick in the nuts happen early on.
Drag racing 90% car, 10% driver.
Road racing 30% car, 70% driver.
And just so you don't think I am a no driving NERD.
I did the Hot Rod Power Tour Long Haul this year on street tires and cheap brake pads.
At the Muskegon autocross I finished 11th out of 68 cars.
I also did the Optima Batteries Ultimate Street Car Faceoff at the end of the Power Tour. Also on 300 treadwear street tires, but I had my Carbotech Pads but no brake ducts. I put the Carbotechs on in the hotel parking lot the night before Eagles Canyon Road Course.
Here is where I finished, Car 36 David Driver A Lambo Gallardo was only .2 quicker in the autox and 2 seconds faster on the road course at Eagles Canyon
http://www.optimainvitational.com/Fa...%20Results.pdf
SO take what I am trying to help you with and do what ya want with it. Just trying to steer you down a road I already been down.
Last edited by FASTFATBOY; 07-16-2012 at 09:13 AM.
#67
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I would build the more powerful engine now, you can easily tune it down if you want. If you build the low power engine, it will always be low power unless you take it apart. Some people I know run second gear in auto cross events to calm the engines power, you could also restrict the intake very quickly in this type of car.
Kurt
Kurt
#68
I'm not the OP.
I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.
Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back.
Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks.
I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.
Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back.
Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks.
Get out on the track with a Spec Miata and try and keep up LMAO. Many a "bad ***"car has had their asses waxed by a well driven Spec Miata.
Do you road course race?
EDIT
I just realized you are the OP.
You are in for a RUDE awakening when you get on track with all that power and you have to point a Spec Miata by and watch him LEAVE you, all of the things I said will come into clarity.
Most all of us who came from the drag racing world have this kick in the nuts happen early on.
Do you road course race?
EDIT
I just realized you are the OP.
You are in for a RUDE awakening when you get on track with all that power and you have to point a Spec Miata by and watch him LEAVE you, all of the things I said will come into clarity.
Most all of us who came from the drag racing world have this kick in the nuts happen early on.
#69
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I'm not the OP.
I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.
Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back.
Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks.
I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.
Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back.
Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks.
It was my first time at that track LOL.
Slicks are worth 4-5 seconds at least over street tires, probably more than that..... the NT-05 arent slicks by any stretch.
I will probably never get on slicks, NT-01 or RA1 or R888 is as close as I will get. I have another year or two on these tires till I move up in grip, I have a lot to learn on these tires. I am not ready to run slicks and won't be for a good long time.
#70
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I would build the more powerful engine now, you can easily tune it down if you want. If you build the low power engine, it will always be low power unless you take it apart. Some people I know run second gear in auto cross events to calm the engines power, you could also restrict the intake very quickly in this type of car.
Kurt
Kurt
#71
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Geebus, some of the **** you see posted on the internet puked up by someone who read it somewhere.
RPM KILLS engines. The end.
In a autox or HPDE car you want tabletop flat TORQUE.
Most autox events in our cars should be run in 2nd gear.
I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.
The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.
Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.
IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.
Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.
If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.
My car ran 137 MPH at the end of the front stretch and weighs 4000 lbs with instructor in the car.
RPM KILLS engines. The end.
In a autox or HPDE car you want tabletop flat TORQUE.
Most autox events in our cars should be run in 2nd gear.
I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.
The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.
Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.
IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.
Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.
If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.
My car ran 137 MPH at the end of the front stretch and weighs 4000 lbs with instructor in the car.
However, one reason the C6.R especially the old 7.0 GT1 cars run such low RPM is they have restrictors on the air intake. Like the high rpm motors they are running what the rules give them.
#72
Just go with the big cube motor. For $1000, that's well worth the money. Just put a medium sized cam in it that is specialized for mid range torque.
I've used NT05s at a few track events and they are great but can get greasy when in extended sessions. That's where the Hoosiers shine. With 500+whp, not sure how long you'll want to stick with street tires.
I've used NT05s at a few track events and they are great but can get greasy when in extended sessions. That's where the Hoosiers shine. With 500+whp, not sure how long you'll want to stick with street tires.