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Discussion Starter #1
As many may know we recently inherited a bunch of really nice parts, including a Getrag, two 40 DCOEs with manifolds, motors, and more.

All that would get us big penalties in LeMons, most likely, but a while back Jay (LeMons boss) promoted us from C to A class and told us to up our game. I told him we'd be asking for a generous residual (They revalue your car to let you spend more on it.) to accomplish this. Well we never did, but it may be time.

John, at Evil Genius Racing, the main tech guy for LeMons, told us to contact Jay to tell him about our side project, an attempt at joining the 130 MPH Club at the World of Speed even at Bonneville this September. I had wanted to do a run, any run, at Speed Week so we could be the World's Fastest LeMons, at least for a year until any other LeMons car attempted a run and beat us. But alas, the cage requirements and other rules made it impossible to keep the Tinyvette a dual-purpose car. So we'll go for a WOS run to have fun, get video, and PR material for us and for Opels in general.

So here is what we're thinking of doing, and what we'll be asking Jay to let us do.

1. Install the Getrag. We'll need the fifth gear if we are to get much past 120 MPH and keep the revs in a safe range.

2. Install dual 40 DCOE carbs. We'll need the high-end power, but we have to do this so that the car is still streetable and road raceable.

3. WOS requires a few small modifications that we will do. We need to put a strap under the drive shaft so that if the u-joints go the car does not attempt to pole vault itself over, well, nothing, but it certainly wouldn't be landing in soft foam. We need to replace our valve stems with steel one. Easy. And lastly, we need to install a window net, one that would be effective even if the door was gone. (I am sure there is some interesting history behind this rule, as well as many of the other rules.) A window net is not required but seeing as we are running with no side or rear glass we've been asking to install a net.

And for fun, we want to install a drag chute. We've got a rear-facing camera on the car, so we just have to have that in a shot, even if the chute is not really essential. We don't have a chute at this time and are looking for a used one, or a loaner, with launching hardware.

Of course we could just put all that stuff on for the Bonneville event and take it back off for LeMons, but I want to run our car in LeMons trim, plus our next LeMons race is 3 days after the end of WOS and it could easily be a two-day drive to get back to California.

I'll be back with the details of our DCOE conversion, Getrag install, news from Jay, etc. Or, maybe we could get a sub-forum so we could put these in different threads. [hint]
 

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Discussion Starter #2
We just got the go-ahead from Jay for the Bonneville mods.

[quote='Jay"]Hey, Mike: Well, you know, I'm a sucker for anything as ill-advised as this plan. I'm fine with all of it--do the Getrag, do the Weber, do the chute...who the hell cares, it's still an Opel GT, right? Just get some good pictures of your adventures to wow me with--$499.99 when you arrive at the track, welcome to the big time! Have fun and good luck! Best &c J[/quote]

First hurdle overcome.

Jay once told me that his dad bought a GT when they first came out. Jay got to drive and thought it was a terrible car. He still hasn't gotten over it. I wonder if a stint in the Tinyvette would change his mind.

Not sure which "big time" he is referring to. Maybe LeMons stand-outs.
 

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Well, that's interesting. I know I'm behind you, and I'm sure I'm not alone.

If the speed record thing does not work out, Texas has this flying mile thing that would love to see you.

My suggestion, is this:

Would you please, set up a Paypal Account.

Now I'm broke, and most of us are suffering from this economy, but even I could spare five bucks in Paypal money, and if everybody here chipped in five bucks you might have a budget for shenanigans, like speed records.

Of course we'd want something outrageous, (later) like a Tshirt we could "Buy," with a picture of Tinyvette on it. Maybe something stupid like Speed record holder under the pic in small type.

Like I said last time....

Everytime you fire that thing up, there's another seventy or so of us, riding along by proxy.

Guys, you have a fan club, and your fans are hungry.

Just a thought.
 

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Well, that's interesting. I know I'm behind you, and I'm sure I'm not alone.

Everytime you fire that thing up, there's another seventy or so of us, riding along by proxy.

Guys, you have a fan club, and your fans are hungry.

Just a thought.
Yepper there a few Opeler's wishing the best.
Mike I'm afraid that the team will have to build a badace engine to break into the 130mph club.
Right now I've got two 48mm T-body's going into a 60mm+ split intake manifold.
 

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Discussion Starter #5
Yepper there a few Opeler's wishing the best.
Mike I'm afraid that the team will have to build a badace engine to break into the 130mph club.
Right now I've got two 48mm T-body's going into a 60mm+ split intake manifold.
It's humbling, knowing we have fans that would even think of putting in money to further our cause. Did I ever mention our very preliminary plan to attempt a Pikes Peak run? ;) Between LeMons races will will be looking for high profile events we can join.

Wrench, we've hit 115 on a closed course (5500 rpm in 4th, 5000 rpm = 105 mph per the dyno). With a little more power and one more gear 130 might be possible. But on salt, and possibly a bumpy run, who knows. But if we fail, no big deal. It will have been fun.

Regarding the Paypal/take up a collection thing, I really think we should get behind RallyBob's serious Speed Week effort. He's going need something a bit north of $10k, and that is a lot, but it's not like we don't owe him for all the help, info, even parts. We've been discussing this out here in Nor Calia. Keith had some good ideas on how to do this so that it minimizes the tax pain.
 

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Discussion Starter #10
Thanks Gary.

We just heard back from Judge Phil, the guy who handles the whole BS Inspection and car classing thing. He also gives the OK on the extra safety upgrades Bonneville requires and the Getrag but is not so sure about the Webers so he told us to bring our old intake and carb set up with us to the next race because the LeMons Supreme Court may hand down a final decision not allowing the side-drafts. Jay interjected, "Aw, I already told them to go for it. And what's the worse that could happen. They win?" Anyway, Phil he gave us an out, either bring Sabine Schmit (Bernhard is currently in Germany. He is a friend of a friend of Sabine. He now has team orders to get her into to accept a seat in the Tinyvette for the Sept race.) to the race, or promise him a LeMons Opel Kapitan in the near future.

I told Phil about OpelWasp's on and off again effort to bring a Manta to LeMons. Phil is dieing to have a Manta in LeMons. We need to get Chris on this project again.
 

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Discussion Starter #11
An update.

The engine is not back together yet, but should be soon. When it is done it will be the same as before, no improvements, but this is the 2.0L motor with a torquer cam, heads shaved (by the PO), and valves and hardened seats, and a Weber 32/36. But, it will be getting dual Weber 40 DCOEs within the month.

That said, here are some numbers I am crunching.

First, here is the dyno plot from our previous motor. The dots are from the dyno plot and the lines I calculated to fit the dots. Our new motor probably had another 10 hp. We'll see. I do plan to dyno it when we are done.


Second, here is our speed over time. I think it is a bit optimistic but can't figure out what I have done wrong. It shows that our 1/4-mile time should be 14.2 seconds (97 mph) but if I add a half second per shift and maybe a second or two for launch that new number would be believable.


Next, speed over distance. I think I recall that we will get a mile to get up to speed before we start passing the timing stations. So, we have to be able to get to 130 mph within a mile. This chart shows that we can, assuming Cd = 0.39, frontal area = 12 sq ft, and shifting at 6000 rpm.


I think this may also be optimistic, but it is at least encouraging. By the way, aero is a big factor here. With a Cd of 0.45 the calculated distance to reach 130 mph doubles.

Last, here's where our power goes, pushing the wind. After 40 seconds we are down to 12 hp and less remaining accelerate the car. The wind is eating up the rest of it.


I have not factored in increased rolling resistance of the salt. Plus, the dyno numbers to not include the power required to turn the front wheels. That's OK for now. Mostly what I can do with the number I have is make comparisons if I change the aero or something else, and it lets me fantasize. Besides, my main goal is to run, have fun, and bring home pictures. If I actually get to 130 mph, wow!

BTW, we have been up to 115 mph on a closed course, so 130 mph is not impossible with the car we already have.
 

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Don't forget to figure in altitude. Bonneville is at a little over 4000 ft above sea level. You will have roughly 16% less power at that altitude. Bring jets with you since an engine jetted at sea level will be very rich at 4000 ft.

And the salt really makes a big difference in total drag. I know a guy with a 270 hp streamliner and so far his highest speed at Bonneville is only 140 mph. He's been trying for the past 6 years to go faster!
 

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An update.

The engine is not back together yet, but should be soon. When it is done it will be the same as before, no improvements, but this is the 2.0L motor with a torquer cam, heads shaved (by the PO), and valves and hardened seats, and a Weber 32/36. But, it will be getting dual Weber 40 DCOEs within the month.

That said, here are some numbers I am crunching.

First, here is the dyno plot from our previous motor. The dots are from the dyno plot and the lines I calculated to fit the dots. Our new motor probably had another 10 hp. We'll see. I do plan to dyno it when we are done.


Second, here is our speed over time. I think it is a bit optimistic but can't figure out what I have done wrong. It shows that our 1/4-mile time should be 14.2 seconds (97 mph) but if I add a half second per shift and maybe a second or two for launch that new number would be believable.


Next, speed over distance. I think I recall that we will get a mile to get up to speed before we start passing the timing stations. So, we have to be able to get to 130 mph within a mile. This chart shows that we can, assuming Cd = 0.39, frontal area = 12 sq ft, and shifting at 6000 rpm.


I think this may also be optimistic, but it is at least encouraging. By the way, aero is a big factor here. With a Cd of 0.45 the calculated distance to reach 130 mph doubles.

Last, here's where our power goes, pushing the wind. After 40 seconds we are down to 12 hp and less remaining accelerate the car. The wind is eating up the rest of it.


I have not factored in increased rolling resistance of the salt. Plus, the dyno numbers to not include the power required to turn the front wheels. That's OK for now. Mostly what I can do with the number I have is make comparisons if I change the aero or something else, and it lets me fantasize. Besides, my main goal is to run, have fun, and bring home pictures. If I actually get to 130 mph, wow!

BTW, we have been up to 115 mph on a closed course, so 130 mph is not impossible with the car we already have.
I noticed that there is a set of 40 DCOE with Cannon intakes on eBay currently.
 

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BTW, we have been up to 115 mph on a closed course, so 130 mph is not impossible with the car we already have.
Which camshaft do you have? This may be the limiting factor. You might have the hp to do 130 mph, but do you have the rpms?

5500 rpms with a 205/50-15 tire and 3.44 rear axle is roughly 115 mph. To run to 130 mph you'd have to hit 6200 rpms in top gear. A stock camshaft makes peak power at 5200 rpms and is falling fast by 6000 rpms.

So unless your camshaft is making its peak power near 6000-6200 rpms, 130 mph would be tough to hit. Maybe eventually, but not in a mile.

I figured that to hit my own designated 170 mph goal at Bonneville, I need to have a cam that will run to 10,200 rpms as my shift points and hit peak power at about 9500 rpms. If I had more distance or was on asphalt that's another thing entirely. My cam has about .600" valve lift and rougly 90 degrees more duration than stock!
 

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Discussion Starter #16 (Edited)
Bob, I have been reading about the salt, how it does create more rolling resistance, and I guess not so surprisingly, less grip. Normally one thinks of grip as a problem when leaving the line but some cars and motorcycles have a difficult time getting speed because of wheel spin, at high speeds. That sure explains the stories of spins at speeds like 200 mph I have heard about, and which is why the salt flat folks are recommending not coming out with an LSD. With a car like ours pushing 80 hp worth of wind at 100+ mph even we could have that problem. We may have to actually use our wing. ;)

I do plan to bring jets, and arrive early enough that I can retune. Our A/F meter will also help.

rmelchiori - Thanks. We already have a pair of these, with manifold. I hope they help.

Edit - I wonder if a NOS system could be rigged up, one designed to merely compensate for altitude, providing a flow rate of NOS that follows engine RPM, and probably just a trickle.
 

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Bob, I have been reading about the salt, how it does create more rolling resistance, and I guess not so surprisingly, less grip.
As an example of this, I know of a gentleman on another forum who has been trying for years to have the fastest Kawasaki KLR650 motorcycle in the world. I ride a KLR as well, and while I haven't explored the top end of this bike, I've heard that it will hit 105 mph or so on pavement in stock form. Stock hp is about 43.

The gentleman who has run at Bonneville has spent thousands on aero upgrades, skinny tires, alternate gearing, and is putting out about 70% more power than a stock KLR650. His best speed to date is 108 mph on the salt. Apparently it goes like stink to 100 or so within the first mile, then it takes over 2 miles to hit 108 mph. The salt is brutal....:yup:

Another analogy may be easier to fathom. Try running on a beach, and compare the ease of this to to running on pavement! That's the thing, the salt might be as hard as concrete in some places, mushy like dry sand in other places, or even covered in water.
 

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Discussion Starter #19
Which camshaft do you have? This may be the limiting factor. You might have the hp to do 130 mph, but do you have the rpms?

5500 rpms with a 205/50-15 tire and 3.44 rear axle is roughly 115 mph. To run to 130 mph you'd have to hit 6200 rpms in top gear. A stock camshaft makes peak power at 5200 rpms and is falling fast by 6000 rpms.

So unless your camshaft is making its peak power near 6000-6200 rpms, 130 mph would be tough to hit. Maybe eventually, but not in a mile.

I figured that to hit my own designated 170 mph goal at Bonneville, I need to have a cam that will run to 10,200 rpms as my shift points and hit peak power at about 9500 rpms. If I had more distance or was on asphalt that's another thing entirely. My cam has about .600" valve lift and rougly 90 degrees more duration than stock!
We've got a torquer cam, nothing radical, but not stock, and your numbers match ours for speed. Our driver reported hitting 5500 rpm at Buttonwillow last year. Our dyno run told us that we would be at 105 mph at 5000 rpm, and with simple ratios we calculated 115 mph.

We will be running with a Getrag 5 speed so we have the revs for 157 mph in 5th at 6000 rpm. ;) In 4th the limit would be 128 mph. We'll have to see what the dyno says on this motor as to where peak power it.

The charts above show exactly what you are talking about. Once we get to about 120 mph the acceleration drops off rapidly. I picture myself sitting in the car and watching the RPM slowly climb, and listening for trouble or wheel spin.
 
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