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PostPosted: January 24, 2016, 4:48 am 
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A Ford 302 is a much smaller engine and will help you keep the small size you want. I think I measured about 19", I can check again for you.

I think you mentioned 3800 RPM at 70, I'm not sure that's going to work. The mileage would be really bad because you would use very little throttle and have a lot of manifold vacuum. If you use a little too much pedal, like maybe hit a pothole, it will burn rubber.

How about a 7.5" clutch?

Maybe the proportions will be OK for you with a little more width if you make it longer, like you're thinking.

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PostPosted: January 24, 2016, 5:20 am 
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esp42089 wrote:
I've modeled this car 6inches wider to accommodate a clutch pedal, and I really didn't like the proportions. I'd have to make the car around 8 inches taller to compensate, and then it's getting pretty big visually with the wheels.
Even if not having aas many options available as 225/45r17, going with something like a 245/45r17 would keep some of the really sticky street tires available while adding an inch in both height and width. Or what about with 225/55r17 tires? You won't be able to get the absolute stickiest compounds, but it'll add 2 inches of height and still has some decent performance tires available.

The extra height would also allow you to raise the engine a bit and go with a more conventional (and affordable) transmission-to-engine interface. The associated raised seating position should allow you to move the pedals back a bit, providing a little more foot room as well.

Lengthening the car to move the engine forward a few inches could also be another way to free up some valuable foot room space for a clutch pedal, either as a stand alone option or in conjunction with some widening.

You might even be able to hide some shoulder belt mounts below the top of the boat tail as well. I believe even the SCCA road racing rules allow for as much as a 20 degree downward angle off the shoulders. At least then you only have the head/neck to worry about, rather than the entire upper half of your body. In my head it doesn't seem like a 'double hoop' pair of bars would look that bad.

Again, I think a lot of compromises will come down to how much time/distance you realistically plan to actually spend driving it.

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PostPosted: January 25, 2016, 1:09 am 
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iadr wrote:
I've sold probably close to 25,000 tires in my capacity as a parts manager for various car dealer. Never sold a 225/45r17. Try 215/55r17, maybe?


225-45-17 is an extremely common german car tire size. Tire Rack shows 156 different types. 215-55-17 only show 56 types for comparison.

horizenjob wrote:
A Ford 302 is a much smaller engine and will help you keep the small size you want. I think I measured about 19", I can check again for you.

I think you mentioned 3800 RPM at 70, I'm not sure that's going to work. The mileage would be really bad because you would use very little throttle and have a lot of manifold vacuum. If you use a little too much pedal, like maybe hit a pothole, it will burn rubber.

How about a 7.5" clutch?

Maybe the proportions will be OK for you with a little more width if you make it longer, like you're thinking.


I thought about the ford 302. I don't have as much experience with it, or what transmissions can pair with it. I have way more experience and comfort with gm motors and transmissions. I've also read a few places that the 302 cuts about 1 inch off the width, but I don't know for sure.

I'm not sold on the 5.5, I mostly just wanted the smaller bell housing to get more foot room. Looking at the big parts stores, it doesn't look like there are many small bellhousings available for larger clutches and flywheels.

Driven5 wrote:
esp42089 wrote:
Or what about with 225/55r17 tires? You won't be able to get the absolute stickiest compounds, but it'll add 2 inches of height and still has some decent performance tires available.

........

You might even be able to hide some shoulder belt mounts below the top of the boat tail as well. I believe even the SCCA road racing rules allow for as much as a 20 degree downward angle off the shoulders. At least then you only have the head/neck to worry about, rather than the entire upper half of your body. In my head it doesn't seem like a 'double hoop' pair of bars would look that bad.

Again, I think a lot of compromises will come down to how much time/distance you realistically plan to actually spend driving it.


I thought about going to a 225-60-18. Those suckers are huge! nearly 29" in diameter. Tire selection is pretty slim though.

So here are some new pictures. I've widened it an inch, it has grown 2 inches in height and length, the driver sits an inch higher, the engine moved forward 2 inches and up 2 inches, wheelbase grew 2 inches, and a series of other tweaks to proportions.
Attachment:
Bug-rev2-F34.JPG

Attachment:
Bug-rev2-side-ST.JPG

Attachment:
Bug-rev2-top-ST.JPG

Also, I had the measurements from my rear axle all wonky. Inside bulge to inside bulge is 49", outside edges are 68", not 58". From my measurements, I think I could use a traditional bellhousing with this layout and it would only stick down below the bottom by 1 inch, so if there are smaller bellhousings, that don't resort to going down to a 5.5 clutch, I'm all ears!


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PostPosted: January 25, 2016, 1:28 am 
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Here are some alternative tires, just because we all like pictures.

Blockley 400-19 Replicas with Knock-Offs:
Attachment:
Bug-Blockley-side.JPG

Attachment:
Bug-Blockley-F34.JPG

225-60-18. I'm actually really liking the look of these. I may need to look into just what is available around 29" in diameter. There might be a 19" wheel or something that is common to a bunch of sports cars near this.
Attachment:
Bug-225-60-18-F34.JPG

Attachment:
Bug-225-60-18-R34.JPG

Attachment:
Bug-225-60-18-side.JPG


Also, just so everyone knows, the preview images the site shows you are horribly compressed versions of the originals. Click on the images to see the nice crisp originals with better detail.

Just putting this here as a reminder to model it sometime: 255-45-20. It has a 29" OD and good sticky rubber available. I think it is an OEM size for some sports cars, cause there is a surprising selection! My favorites are available in this size (Michelin Pilot Super Sport and the Continental DWS). I don't like the idea of 20" rims, but I'll give it a shot.


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PostPosted: January 25, 2016, 3:59 am 
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Here's a picture I took of the 302 in my frame with a ruler. Maybe it's a bit deceptive, the factory lists the width of their crate motor as 18.75". Mine has an aftermarket 7.5" deep oil pan, which I think will match the bell housing. When I started I thought it would be easier or cheaper than reality to put a smaller flywheel on it. I think one of the cheapest routes is looking on EBAY for used NASCAR or oval track bellhousings.


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PostPosted: January 25, 2016, 9:57 am 
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esp42089 wrote:
unbolt the transmission in the passenger compartment and pull in back 2 inches, then pull the engine forward 2 inches and straight up and out.

You can make part of the chassis structure removable if necessary. Search "roll bar connectors" for some examples.

R&R of the engine is ordinarily a major operation, possibly one you'd never have to do after final assembly. But if you don't leave room enough for maintenance, that's gonna suck. Head gaskets and throwout bearings aren't maintenance items any more, but Murphy waits, with long pointy teeth...

Quote:
I think the 5.5" clutch is risky.

You need to call and talk to the clutch makers. Hayes, Quarter Master, etc. Most of the micro-clutches are for "non-shifting" applications; they're just intended to disconnect the engine so you can stop. If they do make a "shifting" clutch, it might be a special order item; engagement curve isn't even a consideration on most racing applications.

Quote:
corrections are within the first 90 degrees of travel in either direction

With 1 turn lock to lock you're unlikely to see 90 degrees of travel. Most cars have around 25 degrees at the road wheel.

Quote:
I thought about a paddle, but it ultimately seemed like it would make it difficult to steer and clutch at the same time

They can turn with the wheel. The steering wheel isn't going to move more than a few degrees under normal circumstances anyway.


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PostPosted: January 25, 2016, 10:08 am 
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I'm not sold on the 5.5, I mostly just wanted the smaller bell housing to get more foot room.


Uh... you're normally looking at a big ol' SEMA-style blowproof bellhousing or a Hewland style bellhouding that is either integral with the transmission or has some unique racing transmission bolt pattern. Most of those also require a special rear-mount starter too.

If you're going for minimum bulk on the bellhousing to get more footroom, you're probably going to have to DIY.


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PostPosted: January 25, 2016, 11:28 am 
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FWIW,

you can get a 4.8L LR4 complete pan to manifolds from LKQ for $350-500. with harness and ecu, probably around 5-700 all in. same LSx bolt pattern on the bell housing, so your options are wide open, and its a pretty proven powerplant. (http://www.hotrod.com/how-to/engine/hrd ... ng-theory/)

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PostPosted: January 25, 2016, 7:43 pm 
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There are adapters to mate a chevy to a vw transaxle and the bus transaxle has a removable bellhousing which is fairly small. Kennedy engineering has heavy duty vw clutches in 8 and 9 inch and also have a double disc setup that will allow you to use 2 discs doubling your torque capacity. You may be able to adapt a transmission to the bus bellhousing. Just throwing out some ideas. Hope it helps. Joe


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PostPosted: January 26, 2016, 12:12 am 
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horizenjob wrote:
Here's a picture I took of the 302 in my frame with a ruler. Maybe it's a bit deceptive, the factory lists the width of their crate motor as 18.75"..... I think one of the cheapest routes is looking on EBAY for used NASCAR or oval track bellhousings.

So on my model, the sbc is 21" wide. The 302 is significantly narrower. Hmmmm. I think a 302 is in my future; I just need to find a nice 4 speed to put with it.

The nascar housings all seem to be for 7.25 clutches. I wonder if there is a way to mate the T-10 up to a ford 302. On Richmond's website they say the T-10 is GM only, but I'm not sure what the limiting factor is. The input shaft?

TRX wrote:
You can make part of the chassis structure removable if necessary. Search "roll bar connectors" for some examples.
.....
Quote:
corrections are within the first 90 degrees of travel in either direction

With 1 turn lock to lock you're unlikely to see 90 degrees of travel. Most cars have around 25 degrees at the road wheel.

I think removable chassis structure will definitely be employed to make maintenance and repair more accessible. I was talking about 90 degrees of steering wheel movement, not tire movement.

TRX wrote:
If you're going for minimum bulk on the bellhousing to get more footroom, you're probably going to have to DIY.

The thought crossed my mind. Seems like the most effective way to make sure the bellhousing is as compact as possible.

1055 wrote:
you can get a 4.8L LR4 complete pan to manifolds from LKQ for $350-500.

I didn't know about that one in specific, though I knew many of the truck engines were good alternatives to the sell-like-hot-cakes LS motors. Thanks!

factorypartsjoe wrote:
There are adapters to mate a chevy to a vw transaxle and the bus transaxle has a removable bellhousing which is fairly small. Kennedy engineering has heavy duty vw clutches in 8 and 9 inch and also have a double disc setup that will allow you to use 2 discs doubling your torque capacity. You may be able to adapt a transmission to the bus bellhousing. Just throwing out some ideas. Hope it helps. Joe

Interesting idea. I don't think I will need the double disk though. I'm hoping not to make too much torque, otherwise I'll need more tire, then the car will be too fast and I'll need more safety equipment because it'll scare my wife more than it already does... We're all familiar with that one, right?

Here is the pimped out rimz: 255-45-20
Attachment:
Bug-255-45-20-side.JPG

Attachment:
Bug-255-45-20-R34.JPG

Doesn't look too bad in CAD. Those tires aren't cheap though and I'm not sure about finding wheels that I like that are that big.


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PostPosted: January 26, 2016, 7:24 am 
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Ford used the t-10 from the factory. You could find it in falcons as well as some other models like the A/C Cobra so the bellhousings and other parts are out there. Its a really nice shifting transmission i have one in my 61 Studebaker Hawk. Pretty much everyone used it at one time from the factory.


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PostPosted: January 26, 2016, 7:34 am 
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As far as wheels im not sure what bolt pattern youll be using but jeep ram pickups and the dodges come with some pretty nice 20 inch wheels.


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PostPosted: January 26, 2016, 3:26 pm 
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Quote:
I'm hoping not to make too much torque, otherwise I'll need more tire, then the car will be too fast and I'll need more safety equipment because it'll scare my wife more than it already does... We're all familiar with that one, right?


I'm glad your on board with this. Almost any modern engine is capable of a silly amount of power in our cars. V8 engines evan more so with the added problem of a lot of torque at low RPM. Landing up with a project your wife doesn't want to go near will take away a lot of the fun...

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PostPosted: January 26, 2016, 9:44 pm 
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factorypartsjoe wrote:
Ford used the t-10 from the factory. You could find it in falcons as well as some other models like the A/C Cobra so the bellhousings and other parts are out there. Its a really nice shifting transmission i have one in my 61 Studebaker Hawk. Pretty much everyone used it at one time from the factory.


Everyone who has one says they shift really nicely. I'll look into the Ford T-10 support a bit to see what is available. I was just going off the Richmond website.

factorypartsjoe wrote:
As far as wheels im not sure what bolt pattern youll be using but jeep ram pickups and the dodges come with some pretty nice 20 inch wheels.


I'll look into that. I also glanced at some aftermarket wheel options and if I don't look at the price, I can find some I like. :shock:

horizenjob wrote:
I'm glad your on board with this. Almost any modern engine is capable of a silly amount of power in our cars. V8 engines evan more so with the added problem of a lot of torque at low RPM. Landing up with a project your wife doesn't want to go near will take away a lot of the fun...


Yep. I hold no delusions that any stock V8 will be anything less than terrifyingly fast or a tire-shredder in this light of a car, which brings me around to my latest thought:

Direct-drive powerglide with a lever operated bypass valve to prevent stalling. My understanding is that this is not exactly a rare setup, and many race cars use a setup like this. My interest is piqued but personal experiences and talk about it on the web seems pretty limited. Anyone here have any experience with this?

If I run a powerglide with a 2.73 rear, I would likely have an easier time managing torque. The direct drive could satisfy my love of engine braking (I actually don't much care about working a clutch, I just want the feeling of engine braking that every auto I've driven lacks). And cruising at highway would be tolerable with an easy 3k rpm at 80 with the 225-45-17s. It gets even better if I go to the monster 255-45-20s (2600rpm to turn 80).


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PostPosted: January 26, 2016, 10:43 pm 
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If youve got any circle tracks near you you can talk to some of the guys there its a pretty popular set up. Theres a book by carl munroe all about powerglides you should get if you want to do it yourself. I believe TCI has a special valve body that will do what you need as far as a valve. Or you could just use an external valve. Hope that helps you some. Joe


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