Dwarf Car Project

Make yourself a jig for tube A-arms,they do get bent. :laugh:
With the tube arms you can use some beefy threaded heim joints on inner arms to make it easier to make front end adjustments for different tracks/conditions

racer54 wrote: I'm just trying to figure out how a KZ motor is going to move all that weight at any reasonable amount of speed. That looks awfully heavy for what torque these motors put out.

Its the low ass gearing in the old Toyota truck rearends combined with a 5 speed motorcycle trans,from what I remember it also had a lot to do with track length on the old dwarf cars as to what it took to keep up. :laugh:

wireman wrote:

racer54 wrote: I'm just trying to figure out how a KZ motor is going to move all that weight at any reasonable amount of speed. That looks awfully heavy for what torque these motors put out.

Its the low ass gearing in the old Toyota truck rearends combined with a 5 speed motorcycle trans,from what I remember it also had a lot to do with track length on the old dwarf cars as to what it took to keep up. :laugh:

They don't use the truck rearends anymore. Most use 10 bolt Toyota (a lot lighter weightwise). The current trend is toward the 8 bolt Toyota or quickchange rearends. Same deal though; motorcycle transmission and rear end gearing. I have seen speeds of 125 mph on some of the road courses with the legends cars.

Sorry about the double post

OK, first question:
I was looking at some parts on the OldKawMan's site. Still can't wrap my head around the low oil pressure situation on the KZ engine. He has oil pumps for the 1981-83 KZ1000J and KZ1100A models and claims "nice upgrade for older models". Is this an upgrade I should pursue for my engine?

I am adding an oil cooler and the "gate", or trap door, to the oil pan. Trying to keep as much oil around the pump and help cooling as I can. I have toyed with a top end oiling upgrade as well. They use them on the legends car engines (Yamaha 1100, 1200 and 1250 FJ/XJ). Anyone have thought on this?

Steve

The old z motors were designed to run on the lower oil pressure,you could try finding a deep sump oil pan and pickup to keep some extra oil in there if youre really worried about it.
Maybe check the classifieds on dragbike.com .

Thanks Jim!
I know you told me that they run low pressure. Still just hard to wrap my thinking around that. I think I have covered what I can for now on the oil pressure and oiling situation. I'll try to move on. lol!

Steve

That's the beauty of roller bearings.

Am thinking the trap door may not be as beneficial in the dwarf car application as it is in drag racing.

Sufficient engine cooling may be a problem, especially with less air flow over the engine, but the oil cooler should help, and the suggested deep-sump pan would provide additional oil supply.

Imo, any net benefits of additional top end oiling would be questionable.

Large Kaw fours are designed to function with low oil pressure, however the volume of oil flow is impressive.

Would concur as to retaining the stock air box.

Good Fortune!

The way those cars are constantly in/out of the throttle and being thrown side/side the trap door is definitely a good idea to keep oil around pick up tube/screen.
The motors are front mounted and sit sideways with cylinder to left side of car.
It would be complicated to keep stock airbox but anything is possible I guess

justfreaky wrote: OK, first question:
I was looking at some parts on the OldKawMan's site. Still can't wrap my head around the low oil pressure situation on the KZ engine. He has oil pumps for the 1981-83 KZ1000J and KZ1100A models and claims "nice upgrade for older models". Is this an upgrade I should pursue for my engine?

I am adding an oil cooler and the "gate", or trap door, to the oil pan. Trying to keep as much oil around the pump and help cooling as I can. I have toyed with a top end oiling upgrade as well. They use them on the legends car engines (Yamaha 1100, 1200 and 1250 FJ/XJ). Anyone have thought on this?

Steve

ALL the KZ900 thru to GPZ1100A oil pumps flow exactly the same.
There is no std swap upgrade from another model.
The only advantage of using a newer one is maybe less internal wear.
The only true upgrade is to buy a 40% extra flow billet pump and deep sump from TURBOMAXX-http://www.turbomaxx.de/oelpumpenkit.html - Price around 1250 euro.(I have one for my 1428 motor - Nice bit of kit).
You may also want to re-think the oil pan gate as it only stops oil surging away from the pump when the engine is mounted with the gearbox orientated to the rear.
Having the engine mounted sideways changes the direction of the surge to the side and renders the normal type oil pan gate largly useless.
You will need to fit a baffle plate to the sump floor at 90 degrees to the crank, preferably in conjunction with either a Turbomax/egli etc type deep sump or modded sump floor below the pump and a downwards extended oil pump pick-up.

Here's a link to my (How to) top end oiler/Dry block thread i posted a while ago.
kzrider.com/forum/2-engine/324427-how-to...block-your-kz9001000
Hope it helps.

Wow! Thanks for all the replies and thoughts.

So here is where I am at. I have a fairly large oil cooler, fittings and hoses. I bought the trap door. May try it out. On the upside, it may help with sharp righthand turns. On further thinking, and thoughts from others; Sharp lefthand turns could be an issue, and perhaps a reason not to use it. For now, I will have to go with the stock pan. Going to skip expensive billet oils pumps and deep sump pan for now. Budget just doesn't allow me to do that right now. I have selved the idea of a top end oiler.

I have ducts and cooling fans. Should be able to move sufficient amounts of air around the engine.

My air cleaner (air filter) idea is very similar to the stock air box. Stock air box would fit. It has rubber velocity stacks inside of it. What I propose to do is use an aluminum top and bottom plate, oval air filter and metal velocity stacks. I could use the rubber ones from the stock air box. Basically, it is very similar to the stock air box minus the sides. My thinking is better air flow.

Planning to stick with the stock 28mm carbs for now. Stage 3 jet kit, and will be looking for a header very soon. The header is going to have to be cut up and reconfigured to fit the chassis. I have 2 different collectors to choose from, a Stinger and the stock USLC (old 600 Racing) collector. Not sure what I am going to do for the muffler yet.

Gasket set came in today. Haven't gotten into the engine yet. Weather is not playing in my favor at the moment. I need to be giving thought as to clutch and ignition system also.

Hope to get my new tow vehicle next week. So chassis should be off to my welder next week as well. Some much needed trianulation to the roll cage and build my door bars also. I am going to go with the new INEX rules and use a shorter height door on the right side and the added bracing in the right side door.

Things are comming along. Just wish I had more time. Season starts in about 1 1/2 months. So still a lot of work to do.

Steve