Impress Formula 1 build thread

[EvolutionRevolution]

As I mentioned a few weeks ago in the "So what did you get in the post today"-thread, I received a Kyosho Impress wreck as well as some parts for the Impress.

The Impress is Kyosho's mid-1990s electric Formula 1 car, and is an evolution of their earlier 1993 F1 cars. Meant as competition for Tamiya's F101 and F102 chassis, those suffered from soft plastics (especially the plastic chassis) and fragile parts, leading to underwhelming performance. Various options were available, such as a carbon chassis, alloy shock and motor mount, alloy diff, etc., but the car never met the success of its Tamiya equivalents. The Impress is the competition version of that chassis, with many improvements such as a standard FRP chassis, adjustable rear wing, front suspension with variable camber, the steering servo in upright position (like on the Tamiya F103), etc. Further optional parts were brought out, including a link conversion set that also replaced the upper front arms with a fully adjustable version. With all options installed, it was apparently a pretty good car.

This will be a build thread about that car. It will be followed by another build thread in another subforum that will cover its descendant, but more about that later...

What I'm starting with is the wreck shown below:

I mostly bought this because it was a cheap way of obtaining a few of the more expensive options: alloy motor mount and a NIP alloy ball diff set. The car also includes half a alloy t-bar mount, but I already have the complete set sitting in a box somewhere. The chassis included is the optional carbon chassis, which unfortunately has some additional holes drilled into it. The chassis also has some front end damage due to a hard frontal impact. The top deck is broken and one lower arm is damaged.
After taking the wreck apart today to check the condition of the other parts, I discovered both lower arms had cracked screw holes, and so did the broken top deck. The upper arms are somewhat warped. The t-bar and carbon chassis both appear to be slightly warped. Furthermore, wear on the chassis indicates it likely was used on the earlier 1993 model of the car, as some screw holes that aren't used on the Impress have marks. Some of the hardware has stripped heads, so it will also be thrown away. I did however encounter some titanium screws in good condition.

So after discarding the truly broken parts I have the following:
- somewhat damaged front wing with okay front body post
- slightly warped t-bar and optional chassis, chassis has various non-standard holes
- half an alloy t-bar mount set
- used spares for the motor pod rear and left side, upper battery deck + body posts, plastic front t-bar mount, servo mount
- a bunch of screws and nuts
- optional alloy motor mount, a bit dirty
- NIP alloy diff set

In my boxes of spares I should have:
- NIP FJW-4 alloy t-bar mount set
- various front uprights
- two sets of wheels + tires
- possibly a Cross king pin set for the original 1993 chassis
- NIP FJW-23 chassis protector

As mentioned in the other thread I also bought some optional parts:

- NIP white adjustable rear wing
- NIP lower front arms
- NIP FJW-20 suspension kit, which converts the t-bar car to a link car with Trinity Evolution 10-style front suspension

Waiting for transit are:
- NIB Kyosho Impress car kit
- NIP alloy shock set, which I need anyway to be able to use the FJW-20 option

Just bought on Ebay:
- NIP upper front arms
- NIP FJW-21 king pin kit

Things to buy:
- FJW-5 spring set
- carbon axle
- new carbon chassis
- FJW-22 hard (?) diff rings
- a body that fits, which may be problematic because although the front and rear wing mounts are Tamiya compatible the chassis itself has a shorter wheelbase than Tamiya F1's. However, some of the body molds are supposedly still used by manufacturers other than Kyosho...

[EvolutionRevolution]

Just bought on Ebay:
- NIP upper front arms
- NIP FJW-21 king pin kit

Received these. The kingpin kit consists of two titanium kingpins and a set of teflon coated aluminium balls, which saves 1.4 grams of weight. What's less hot is that only one set of springs is included (the same ones as in the Impress chassis kit), meaning I still have to buy another option to get all available spring rates...

[EvolutionRevolution]

This will be a build thread about that car. It will be followed by another build thread in another subforum that will cover its descendant, but more about that later...

Or maybe not, because said kit (Cross FireForce) is currently AWOL after the parcel went into customs and came back out of it to go exactly nowhere. I know the amount of import taxes I'll have to pay and that I'll need to sign for it, but the parcel is out of customs and not in the postal system yet according to Dutch Post But such a transfer doesn't take them close to a week...guess I'll contact them again tomorrow to ask where the heck the parcel went and whether they can locate it.

Waiting for transit are:
- NIP alloy shock set, which I need anyway to be able to use the FJW-20 option

This on the other hand has been received.

[klavy69]

Dammit, I hate when that happens. Good luck with the package making it into your hands.

Todd

[EvolutionRevolution]

Dammit, I hate when that happens. Good luck with the package making it into your hands.

Todd

Well, it turned up today. Seems like where up to last year import taxes were added to items by the Dutch postal services themselves, it now is directly handled by customs (which results in a needless delay of several days and confusing tracking statuses ).

[klavy69]

but at least the package showed up...good things are better than bad things to hear about

Todd

[EvolutionRevolution]

My Impress kit turned up today, which lets me amend my things-to-buy list:

Things to buy:
- FJW-5 spring set

Bought, received last week.

- FJW-2 carbon axle

...needs to be joined by FJ-12 diff joint set and FJ-50 Diff cone set (both of which I've just bought), because the diff as used by the stock Impress mounts to a Pro-10-style rear axle, uses very small specific diff rings, and has a very strange design overall for a ball diff. Hopping it up requires buying the whole rear axle assembly of the original Kyosho direct drive F-1 car. I also need to check whether it's possible to add a Tamiya-style thrust bearing instead of the single sideways-load-bearing bearing it normally uses.

- FJW-1 new carbon chassis
- FJW-22 hard (?) diff rings

The rear axle thing does mean I can now skip FJW-22, since those diff rings are for the original Impress ball diff and I won't be using that one.

So new list:
- FJW-1 carbon chassis
- FJW-2 carbon axle (might need to check whether I can use a Tamiya carbon axle)
- body

[EvolutionRevolution]

...needs to be joined by FJ-12 diff joint set and FJ-50 Diff cone set (both of which I've just bought), because the diff (...) uses very small specific diff rings, and has a very strange design overall for a ball diff.

Okay, so this assessment was based on the drawings in the manual, which turn out to be pretty inaccurate in their proportions . Now that I am actually looking at the parts, I can see that the diff rings are normal-sized.

- FJW-1 new carbon chassis
- FJW-22 hard (?) diff rings

The rear axle thing does mean I can now skip FJW-22, since those diff rings are for the original Impress ball diff and I won't be using that one.

Scratch that, new new list:

- FJW-1 carbon chassis
- FJW-2 carbon axle (might need to check whether I can use a Tamiya carbon axle)
- FJW-22 optional diff rings
- body

[EvolutionRevolution]

Guess it may be time to show some pictures.

Open box:

Instruction book:

Parts lists:

Exploded view:

Rest of contents of bag with instruction book and exploded view:

Box containing wheels on sprue, foam tires, and FRP chassis:

The FRP chassis is a bit too flexible, much more than a Tamiya F-101 or F-102 chassis.

Included wings:

The rear wing is adjustable in three positions.

And two big bags of parts:

continued next post...

[EvolutionRevolution]

Bag #1 contains these parts:

Close ups of each parts tree:

Besides the servo saver, which is made from white nylon, most parts are either made from tough fiber reinforced nylon or a glossier plastic, fortunately not the extremely fragile plastic Kyosho used on several other kits, even though it looks quite similar.
The diff parts (last picture) curiously include two left diff halves: one for the Impress axle and one for the old direct drive axle, even though the instructions say you can only use the optional alloy diff for the latter axle. Perhaps Kyosho had planned a kit that used the old axle?

[EvolutionRevolution]

The other bag contains various additional bags:

A bag with the axle, t-bar, spurs, and various tools:

As can be seen, the rear axle is Pro-10 style (but 6 mm diameter only), while the original Kyosho direct drive rear axle is basically a Tamiya F-101/102 clone.

Diff parts and ball bearings:

More metal parts:

And a bag containing mostly screws:

So far for the basic kit.


Optional parts bought up to this point:

Carbon chassis and aluminium motor mount:

There are several additional holes in this chassis, and it's also missing two holes present in the Impress FRP chassis. The motor mount needs a cleaning session and includes an additional tapped hole because the previous owner apparently ran his car with a swing bar...

FJW-5 spring set:

Also includes optional kingpins for original Kyosho direct drive F-1.

FJW-21 special king pin set:

Can only be used on Impress, preferably in combination with optional suspension conversion set, not suitable for Kyosho's original direct drive F-1 car.

The following two options were originally meant for Kyosho's first direct-drive F-1 car:

FJW-7 Formula oil shock:

The shock body doesn't really look like a Kyosho-designed part, does it? No anodizing, installation requires modification of the top deck.

FJW-8 Ball differential set:

Again, no anodizing. I suspect the spurs are Tamiya-compatible.

These two alloy options are very similar to Cross' early alloy optional parts for Tamiya and Kyosho cars, which, considering Cross did development work on Kyosho's direct drive F-1 cars, probably means they were made by Cross for Kyosho.

[EvolutionRevolution]

Some more wings:

FJW-12W Maisonette wing (white):

Kyosho sold this wing in several different colors (white, black, red, yellow, blue) to replace the all-lexan wings included with their F-1 body sets. The one in the Impress box is exactly the same (but black).

Used alternate front wing belonging to one of Kyosho's body sets:

I'm quite happy I have this, because it gives some more body options.

Finally, the FJW-20 Suspension kit:

This option add Trinity Evolution 10-style adjustable front and rear suspension, replacing the t-bar rear suspension with a linked pod (interesting tidbit: Kyosho Japan was the importer for Trinity in Japan).

The pod-plate is made from graphite (that I'll need to compare with the chassis plates on my Evolution 10, because the stuff looks verrrrry similar).

Anyone familiar with a certain more recent F-1 car will probably recognise certain aspects of the FJW-20 instruction sheet...

[EvolutionRevolution]

Even though I haven't got all of the parts required to complete the car yet, I figured I would get started. This is going to be an entirely out-of-order build. I'll start with the rear pod.

Parts:

Comparison of alloy motor mount with stock plastic part:

Assembling the plastic parts of the pod was quite hard, as the plastics used are very difficult to work with. Each screw had to be threaded into its hole by screwing it in, then backing up, then screwing it in, then backing up, etc.

Anyway:

On the above picture the tabs guiding the parts together can be seen. Still, the pod was assembled on a flat surface to keep it squared. I really recommend first tightening the screws in the left front corner and right rear corner, otherwise the pod will end up tweaked.

Result:

Compared to Tamiya's F-101/102/103 pods I really like the integrated diffuser. Also note that just like the Tamiya F-103 pod, the Impress' pod has the motor offset to the left of the car to diminish torque steer.

[EvolutionRevolution]

The other part that got assembled tonight is the rear wing. Parts:

Assembled:

Quite realistic.

The wing offers three downforce settings: high, medium, and low:

The manual tells you to use the high downforce setting, I went with the medium one.

The plastic (nylon) used by Kyosho for the rear wing is a lot softer than that used by Tamiya (ABS), which means the wing will get damaged less quickly:

Although I wonder what the consequences for downforce will be:

One of the part trees includes an alternate wing mount for a low profile Indycar-style wing:

You'll need to provide the wing yourself. For those that really want to go lightweight, the rear pod has grooves into which wing wire can be inserted (held on with washers and screws):

Again, no wing (or wing wire, or wing buttons...) included for this option.

That will be it for a while. I also rummaged through some parts boxes in search of the two optional parts I should have. I didn't find the alloy t-bar mounts , but did find the Cross kingpin set and also the gear diff parts for Kyosho's 1993 F-1 car (the predecessor of the Impress):

The gear diff mounts to the regular rear axle, just like the alloy diff set. So now I have three options for the diff, two of which go on the same axle. The Cross kingpin set is mostly comparable to Kyosho's own FJW-5 option, but the kingpins are slightly longer.

More later.

[klavy69]

Watching with full intensity

Todd