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Running 11-Second 1/4 mile with 2.56 gears, stock stall, and 225/70-15 Coopers


Dragginwagon467

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Long post, should be entertaining for fellow gear heads.
 
For those not on social media, and maybe for those that are on social media too, what a racing/cruise-in season it has been! My goal for my Monte Carlo has always been a street cruiser first, quarter mile car second, and a sleeper always. Maintaining the factory appearance is helpful considering I’ve been playing around with the idea of running in the FAST Class of the stock appearing racing series. So far, I’ve been able to attend the FAST Test and Tune events in the spring and fall, but I’m only a few details away from becoming class legal and running in the official events.
 
For me, the goal for the car has always been 11-Second quarter mile times. Don’t get me wrong, 12s are still very respectable, but 11s puts you in a different league, even if the division is completely arbitrary. I know it’s not just me, there’s something inherently fascinating about cars which are sneaky fast. Cars that make you wonder, “How did he do that?”
 
I put my own twist on things, as I like to combine mildly sneaky fast with having a car friendly enough your wife can jump in it and drive it anywhere. To that end, that’s why I kept the 2.56 gear and factory converter when swapping in my first big block. It’s also why I’ve chosen to build the new engine to compliment these pieces.
 
This post outlines how I took a car running high 12-Second passes to a car capable of running high 11-Second passes, and doing so with the factory gear, torque converter, stock wheels and tires, and a cam mild enough to work with power brakes. The best part is, anyone should be able to do it, and have their wife drive it. Enjoy!
 
Season Opener
Started off in May with a personal best of 12.92 @ 108.96 mph with my 781-headed 467 at US131 during the FAST Spring Opener.
 
The Engine Build
Then in July, the 496 project I've been working on for two years finally came together:
  • 496 (4.310" x 4.25")
  • Built following Mark Jones (VortecPro videos - 620 hp, 467 build videos)
  • Scat 4.25" cast crank
  • Scat 6.358" I-beam rods
  • MAHLE Power Pack 18cc pistons and rings (1.5/1.5/3.0mm), 10.1:1
  • Isky 275/284 HR cam, 228°/238° @ 0.050", 0.553"/0.578" (ground on 111°, installed at 109°)
  • Isky 8005A springs 
  • Howards 91167 lifters 
  • Factory 049 oval port heads (2.19"/1.88" Ferrea valves, 11/32" stems)
    • Intake guide replaced, bronze liners in intake and exhaust
    • Ported according to VortecPro videos, flowed on a 4.5" fixture
    • Flow Bench Results 049 Casting
      • Lift Good Port/Bad Port/Exhaust
      • 0.200 153.1/152.0/122.2
      • 0.250 192.5/191.1/142.9
      • 0.300 229.3/228.6/161.1
      • 0.350 260.3/260.0/177.8
      • 0.400 283.7/267.7189.4
      • 0.450 297.4/273.3/197.9
      • 0.500 305.4/281.6/204.7
      • 0.550 307.9/288.0/212.0
      • 0.600 303.5/296.1/217.1
  • Scorpion 1.7 Rockers
  • Performer RPM Air Gap
  • 950 ADP carb on dyno (box-stock Holley 3310 750 vacuum secondary on the car)
  • A few issues prevented the engine from reaching its potential on the dyno.
    • Intake valves were floating at 5300 rpm (look at the actual horsepower)
    • Too much oil (7 qt pans only need 5.5 qts), and
    • Incorrect correction factor on the dyno.
       
Dyno video:
 
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The engine came off the dyno July 3rd, July 5th I was at Jegs picking up spring locators and shims. While I was pulling, measuring, and resetting the intake valve spring installed height, my best friend pulled the engine and had it on the ground.
 
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Before coming in that night, the 496 was sitting in the car. Blue Suede Cruise was that Saturday so there were consecutive 11 PM evenings over the course of the next several days, with only one rain out (all car work occurs in my driveway). I proceeded to tie up the loose ends, which involved cutting out the core support for a HD radiator and switching original fan tunnel over to the big block shroud.
 
The Maiden Voyage
The weeklong effort culminated in a local cruise-in Friday night (didn’t even have the clutch fan installed due to time constraints), with a shake down run after installing the fan and lowering the engine oil level. Let's just say, I knew the maiden voyage down the track was going to be epic when the Draggy showed 0-60 as 4.8s with four passengers and a fully loaded trunk (and this was on 15 year old 255/60-15 Kelly Charger radials). 
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Let's just say, it sounds great and drives unbelievable. The 496 idles smoother, with about 13" of vacuum at 840 rpm, than the 467 it replaces. It has more mid-range, more top-end, more everything. That's with keeping the same carb and distributor - no changes at all to these pieces. The car is easy to drive...but when you stand on the throttle, you had better be pointed in an appropriate direction because it picks up speed at a phenomenal pace. The best way to describe it, it feels like a healthy small block Chevy with 3.42 gears, only you’re gobbling up much more real estate with each gear change. It's a unique experience, for sure.
 

 

6:30 AM Saturday morning came quick, as my son and I began our hour and fifteen minute drive to Summit Motorsports Park.

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It was an uneventful drive. We arrived, completed registration, and as we pulled into the car show lot, we noticed a group of first-gen MCs nestled together. To my delight, they said there was space available next door, so the group of three First-Gen MCs belonging Paul and his two sons, Jared and Kaleb, became four. 
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After a quick chat, I figured out that Paul owned the hard-leaving, blue '70 Monte Carlo which caught my eye in another friend's Facebook post (see photo below). 
233263590_Paul1970MC.jpg.fed667c7f0488dcbbc3bba28d064ed6b.jpg
 
After swapping details, I figured (Paul would agree afterward) we'd be a pretty even match as I was guessing my maiden voyage would be in the 12.3-12.4s range, and Paul ran similar times. After Paul and his boys took a short warmup drive through the show (they camped the night before), we paired up in the staging lanes. After a short delay for track clean up, this turned out to be one of the best drag races I've had in a several years (the best was against my best friend a few years ago).

To set the scene a little better, Paul's '70:
  • 489
  • factory iron heads
  • 0.600" roller cam
  • RPM Air Gap
  • Full exhaust w/ cutouts open
  • 3.73 gears
  • 700R-4, 3000 stall
  • 275/60-15 M/T ET Streets
 
On paper, it would appear Paul had the advantage of a similarly built engine but a much better setup car. All I knew is that I had been studying parts, builds, videos, and ported these heads to the best of my ability, and was confident we were going to run similar times, despite what appeared to be an obvious mismatch on paper (and do it with my son riding shotgun, to boot).
 
i won the battle at the tree, but Paul’s better tires, gearing, and converter quickly ate up my initial advantage and pulled ahead. At 330’, my front bumper was even with his rear bumper and it looked like I’d lose for sure, but my horsepower was kicking in, and It was a race out the back door, with the only question, “do I have enough real estate to reel him in?”

Watch for the head-to head battle for yourself, my son was quite excited.
 
 
That was a close race! For a drive in, unload your junk, call out your opponent, and run heads-up, side-by-side with another 1970 MC race, we could not have asked for a better race. Pure awesome!
 
Check out the ETs and margin of victory.
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On the next pass (much more boring race), I came out a little harder (definitely still not flat-footing the throttle as I know the rear end had a tendency to axle-hop on the street at that point so I was doing everything I could to avoid spinning my 255/60-15s at the time). Anyhow, I dropped in 5 gallons of race gas and pass #2 for the fresh 496 netter a 12.29 @ 116.45 at 4275 lbs.
 
As a gear head, Blue Suede Cruise was one of the best events I’ve ever been to. In addition to Paul and his sons, I met Mike ('70 MC) and Jim ( a beautiful, highly optioned '72), who also have first-gens. For those considering coming to Monte Carlo Take Over at BSC next year, the event is incredible and will not disappoint. I plan on camping, just not sure how yet.
 
Regroup and Improve
After BSC, I knew addressing the wheel hop was a high priority so I ordered all new rear control arm bushings and the steel plates to box the lowers.
 
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With the rear end squared away, my best friend and I rebuilt the front suspension, sandblasting and painting the A-arms and brake hardware as well as exchanging the Hotchkis 1” lowering springs with Moog factory big block replacement 6330s. While we had the car in the air, we installed a drive shaft loop (UMI, and it fit like a glove) for added safety.
 
You can only imagine what a difference the springs made for weight transfer, with the additional stored energy. Shocks are still Bilstein.
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Somewhere in the middle of summer, the factory transmission started taking its sweet old time shifting from first to second, which is a pretty important shift when you’re only using two gears going down the strip.  The transmission was replaced with a TH350 which was rebuilt in the early-2000s, but I kept the original 1970 torque converter.
 
For comparison:
  • Hughes 10”, top
  • 1970 TH350 SB, middle
  • TH400 RV, bottom
 
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With wheel hop gone, weight transfer now working like it should, and the transmission shifting like it should, I replaced the 15 year old mix-matched tires for a full set of 225/70-15 Cooper Cobras (black wall out of course) and switched back to the factory, body-colored hubcaps (from the rally wheel trim).
 
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I was having idle cooling problems with my new (to me hand-me-down) HD two-row aluminum radiator (due to narrow core, it created a large gap with the fan shroud), so I measured the core and a friend and I headed to the local pick-a-part in search of a suitable donor. Electric fans from a 2005 Chevy Equinox were the closest match I could find to the 18”x28” core, so I plunked down $35 for the dual fans and relay setup. I installed them before heading out on the Hot Rod Power Tour, and it’s a good thing I did.
 
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Enjoy!
Having never been on Power Tour before, I can tell you, I was not mentally prepared for the 94°F stop and go traffic between the small towns. It literally took 30-45 minutes waiting in stop-and-go traffic waiting to reach the four-way stop or stop light in these small towns between Norwalk and Dayton. I literally drank a gallon of water between Norwalk and Dayton. Anyhow, the car never got over 175°F, performing well the entire drive. 
 
Enough complaining, what about the racing? Unfortunately, really bad air and poor track prep wouldn’t allow me to dip below 12.46 @ 115. Disappointing! So much in fact, I used the track time at Norwalk to offer those interested in a ride down the track the opportunity for a unique experience (not many people have felt a near 600 hp/615 hp in a street friendly package).
 
A few comments were golden. One father/son pair loved their first 12-Second pass. Actually, it was their first pass down the track, ever, I hope I didn't set the bar too high. A couple other passes included fellow First-Gen Monte Carlo owners (Jim and Joe). 
 

Lucas Oil Raceway in Indy wasn’t any better. After working through one of the most unprepared tech processes I’ve ever seen (I don’t blame them, a whole bunch of things happened quickly to lead to the disorganization), I made two passes, with 12.52 @ 115 mph being the best, with heavy spark knock off the line (so I retarded the timing for the heat and humidity)  

 

Missed Opportunity

Of all the events I did make it to, I was really looking forward to the Airfield Drags in Three Rivers, MI.

https://www.facebook.com/airfielddrags

In the end, the event was rained out, then rescheduled to a day I could not attend.

https://www.facebook.com/events/194336716079579

If you get the chance, check it out, it was way cool!

 

Get it Done!

That brings me to the last chance of the year to run 11s - the FAST fall track rental at US131. I wasn’t taking any chances this time, I reset the timing to 37° and I picked up 6 gallons of CAM2 110 octane race gas the night before and packed it in the trunk.
 

Mentally, I had a plan and was going to stick with it - get there early, let the car cool, air down the rear tires to 25 psi, drop in the race gas, pull the fuse the electric fan, and hope for the best. I left the house at 5:30 AM, stopping only to clear the frost from my windshield and to pick up my Dad and Uncle and proceeded to drive my Monte 3.5 hrs (264 miles) to US131, in an attempt to make the dream became a reality.

Upon arriving at the track, the fuel tank was nearly empty, which was perfect as I dropped in the race gas to work with the timimg. From there, I checked the fluids, lowered the rear tires to 25 psi, and removed the last fuse for the electric fans (each fan is individually fused, under 75°F, only one is needed, it was a cool day at the track so I could get away without any fans at all). 

First pass, I was cautious and smooth on the accelerator. It came out smooth and hard, but I didn’t have my Draggy set up and the guy I raced took both time slips so I wouldn’t find out what I ran until after the second pass.
 
I knew the air was going away quick so I connected my Draggy and hot lapped it
 
Well, it happened! 

Video of my first confirmed 11-second pass (second 11-Second pass, actually). Yes, I was excited!
 
 
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And yes, I did it without a tach or shift light in the car.
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After the second pass, I hunted down the first time slip, which turns out, was also an 11-Second pass.
 
Knowing that the traction was there, on the third pass, I completely flat-footed the launch to a 1.88s 60', running a 11.86s.

In summary, three 11-Second passes in a row:
  • 11.93 @ 119.46 (soft launch, best air)
  • 11.84 @ 119.27 (a little harder launch, wrose air)
  • 11.86 @ 119.27 (completely flat footed the launch, but the air was a going away)
 
Knowing I gave it all that it had, the air was going away, I needed to be home for the kids, and most importantly, I had not broken anything, I decided to call it a day. Project "Run 11-Seconds with 2.56 gears, stock stall, and 225/70-15 Coopers" an unequivocal success! Race weight was about 4100 lbs, give or take. 
 
Many people to thank, my friends (Scott, Mark, Doug, and Will), my wife (for her patience), Mark Jones (VortecPro) for great general advice and videos on how to port the 781/049 heads, and Mike Graham (Graham Performance Engines) for the performance headwork, machining/assembling, flow bench and dyno testing.
 
Stay tuned:
There’s a legit VortecPro engine in the wings for next year. It should be exciting, I plan on trying to run 11.50s with a little more torque and horsepower, using the same basic drivetrain.
 
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496 Photo.jpg

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  • Dragginwagon467 changed the title to Running 11-Second 1/4 mile with 2.56 gears, stock stall, and 225/70-15 Coopers

Great write up for sure, I'm going to have to go back and re-read it a few more times. I saw your last post on the FB page, (they made it private again and I don't do FB🤪)

What app are you using for the video ? Its crystal clear. I was thinking of getting Dr Dial in for next season, so much fluctuation in temps I'm tired of breaking out lol 

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8 hours ago, MC1of80 said:

Love the write up! Great job on your build! 

Thanks man. There has to be people who would enjoy hearing about the adventure - I know I love to read about other’s adventures. 

16 minutes ago, DragCat said:

Great write up for sure, I'm going to have to go back and re-read it a few more times. I saw your last post on the FB page, (they made it private again and I don't do FB🤪)

What app are you using for the video ? Its crystal clear. I was thinking of getting Dr Dial in for next season, so much fluctuation in temps I'm tired of breaking out lol 

Thanks. It’s long, but I’m a detail guy…what can I say. 

There were too many spammers, and Facebook was taking away the member approval process for public groups. 

It's the Draggy app, which works with the Draggy Performance Meter.

dragy 10Hz GPS Based Performance Meter https://www.amazon.com/dp/B077KKPMTB/ref=cm_sw_r_cp_api_glt_fabc_YZPFF5CVMW0GQASMF91W

I mount my iPhone 10 with extended battery using this phone mount.

Car Phone Mount - Cell Phone Holder for Car Windshield Compatible with iPhone X XS Max XR 8 Plus 7 Plus 6S Plus 6 Plus SE Samsung Galaxy S9, S8, S8 Plus, Note 8, S7, S6, S5, Google Pixel XL by DaVoice https://www.amazon.com/dp/B00Q3I8H8...abc_HQSMNHCWPHABC5K8HYMY?_encoding=UTF8&psc=1

My car does not leave hard so your mileage may vary. 

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9 minutes ago, 714024SPEED said:

Great story. Love the sleeper look with the hub caps 

Thanks. Putting the hubcaps back on is probably my third favorite modification (locker, engine, hubcaps). I’m always worried about losing one in a pothole and not realizing it. They’d be challenging to replace. 

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1 hour ago, Dragginwagon467 said:

Thanks man. There has to be people who would enjoy hearing about the adventure - I know I love to read about other’s adventures. 

Thanks. It’s long, but I’m a detail guy…what can I say. 

There were too many spammers, and Facebook was taking away the member approval process for public groups. 

It's the Draggy app, which works with the Draggy Performance Meter.

dragy 10Hz GPS Based Performance Meter https://www.amazon.com/dp/B077KKPMTB/ref=cm_sw_r_cp_api_glt_fabc_YZPFF5CVMW0GQASMF91W

I mount my iPhone 10 with extended battery using this phone mount.

Car Phone Mount - Cell Phone Holder for Car Windshield Compatible with iPhone X XS Max XR 8 Plus 7 Plus 6S Plus 6 Plus SE Samsung Galaxy S9, S8, S8 Plus, Note 8, S7, S6, S5, Google Pixel XL by DaVoice https://www.amazon.com/dp/B00Q3I8H8...abc_HQSMNHCWPHABC5K8HYMY?_encoding=UTF8&psc=1

My car does not leave hard so your mileage may vary. 

Thanks for the links , I'll have to do more research since I mainly run 1/8 mile track.

As far as details, I'm all in. Being on the low end of the learning curve the more the better lol. 

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That’s awesome, I got a dragy earlier this year for my 402/400/12 bolt 70 Monte. Basically stock engine and headers it was running 15.1x’s quarter and 2.5x’s 60 foot on the street. Changed from some worn out 255/70/15 BFGs to a pair of used 275/60/15 MT-ET radial pros and dropped to 2.06 60ft and 14.23 quarter just by learning how to launch and drive the car. I’m putting together a 496 for mine too, 049 heads, comp .601/6.10 custom hydraulic roller cam and 9.5:1 scat rotating kit. I can only hope it’ll run like yours!

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3 hours ago, 70MC402 said:

That’s awesome, I got a dragy earlier this year for my 402/400/12 bolt 70 Monte. Basically stock engine and headers it was running 15.1x’s quarter and 2.5x’s 60 foot on the street. Changed from some worn out 255/70/15 BFGs to a pair of used 275/60/15 MT-ET radial pros and dropped to 2.06 60ft and 14.23 quarter just by learning how to launch and drive the car. I’m putting together a 496 for mine too, 049 heads, comp .601/6.10 custom hydraulic roller cam and 9.5:1 scat rotating kit. I can only hope it’ll run like yours!

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Sweet car! Love the Draggy, interesting data.
 

Good luck with your build, you got the right bones. The biggest single difference you can make is the heads. Don’t just watch the VortecPro videos, study them and  understand what he is saying. Use your wits, I showed it works. Find a local performance machinist, who has the skill and tooling to do good head work - I skipped two machine shops because they didn’t understand why I wanted new intake guides, bronze liners, 11/32 valves, a 5-angle valve job, or what a bowl hog was. Getting those things right is the foundation to build on, buy a Harbor Freight die grinder and a double cut 6” flame bit and follow the videos. Take notes, write them down. Have a plan and execute on it.  I was lucky to find a machinist with a flow bench, who has the Brzinski fixtures and adaptors and knows how to use them. 

The head gasket matters, and needs planned out before you take the block to the machine shop. The 1037 gasket is helpful, it improves cooling (requires drilling a couple more holes, hint: do this before boring with a plate) and is friendly to the small bore. You will want to use this gasket for relieving the tops of the bores, and to de-shroud the valves in the head. 
 

All pistons are not created equal. Ring thickness is part of it, but dome shape is important too, as is weight and material. MAHLE Power Pack pistons flat out work, especially with the chamber mod Mark shows in his video. 
 

Keep the cam small, it not only improves torque and idle vacuum for brakes, it allows you to use a simple vacuum secondary carb, and it works flawlessly. It also makes the car more fun to drive, especially with less gear.  Besides, do you want to run 10s or 11s?

What gear and converter are you going to run?

I hear 2.56 gears aren’t too bad :)

 

PS here’s a few of my Draggy screenshots for comparison. 

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The machine shop we have here in town is pretty good, they’ve being building this same 496 build with a slightly bigger cam since the early 2000s, netting right around 600 horsepower and a bit more torque.

 

I was going to have them do the intake port work to try to get into the 300-310 range for the intake ports, without getting too big with the port itself. They already did the 2.19/1.88 valves and valve job as well as some unshrouding in the combustion chamber. I bought the heads from them with the intent to have them finish them once I can afford to do so. I hadn’t done as much thought on the head gasket as I was waiting to figure out the exact thickness until I can get a burette on the heads and figure out the chamber size, then I was going to have the machine shop 0 deck the block and go for a .040 quench to try to help with detonation. With that compression and iron heads do you have any issues with detonation?

 

The gear that I have in it now is a 3.73, true trac rear diff with 33 spline axles. Chromoly front and rear yoke and a better driveshaft from a local shop. I’m not sure what converter yet, I was going to get the engine together and that way I have the dyno to refer to and call around. I’ve heard ATI, PTC, Jake’s, and a handful other places are all reputable.  

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I have a PTC in Big Red. No complaints at all. Actually love it! Acts like a stock converter on the street and  flashes to 4k at the track. Kinda the best of both worlds. Well, as close as possible. Lolol. Have had other name brands and recommend the PTC. 

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2 hours ago, 70MC402 said:

The machine shop we have here in town is pretty good, they’ve being building this same 496 build with a slightly bigger cam since the early 2000s, netting right around 600 horsepower and a bit more torque.

 

I was going to have them do the intake port work to try to get into the 300-310 range for the intake ports, without getting too big with the port itself. They already did the 2.19/1.88 valves and valve job as well as some unshrouding in the combustion chamber. I bought the heads from them with the intent to have them finish them once I can afford to do so. I hadn’t done as much thought on the head gasket as I was waiting to figure out the exact thickness until I can get a burette on the heads and figure out the chamber size, then I was going to have the machine shop 0 deck the block and go for a .040 quench to try to help with detonation. With that compression and iron heads do you have any issues with detonation?

 

The gear that I have in it now is a 3.73, true trac rear diff with 33 spline axles. Chromoly front and rear yoke and a better driveshaft from a local shop. I’m not sure what converter yet, I was going to get the engine together and that way I have the dump to refer to and call around. I’ve heard ATI, PTC, Jake’s, and a handful other places are all reputable.  

Zero deck

1037 is 0.039”, but it allows better cooling to stave off detonation

-18cc dome

049 milled 0.010” to get them back to 120cc (laying back the chamber to improve exhaust flow, polishing, and de-shrouding had them up to 122cc)

93 octane Shell 

I’ve only heard detonation on a 94-95°F day, after extended idling in the staging lanes and then pulling on the race track, right off the line. Think Hot Rod Power Tour, which is not a normal occurrence. Keep in mind, my converter and gear super load the engine at low rpm, which is the worst possible condition. My chambers are polished, and valve reliefs ground into the tops of the bores, so I’ve lost a few cc there too. A larger cam would not build the same compression, especially down at low rpm, and a looser converter and deeper gears will not load the engine in the vulnerable rpms.

In any case, I’ll run a few gallons of race gas on track day, it’s cheap insurance. 

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Had another opportunity to make a few laps at MIS yesterday for their 13th annual MIS Cares Track and Toy Drive. Good times for a good cause. 
 

Track was a little frosty, tires breaking loose at 50 mph 😂 settled down and had some fun. 
 

 

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36 minutes ago, 1970mcss said:

Looks like a good time. You needed to get the pickups and suv s out of the way. Happy holidays

Yeah, the issue was two fold, slick track and traffic. I could have easily been at 125+ but then I would need a non-slick area to slow down before catching up with the traffic. I’m a pretty calculated kind of guy, the math wasn’t adding up 😂 

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