Monday, November 3, 2008

Toyota Unser 7K Engine

The Toyota K series was a straight-4 engine produced from 1966 through 1988. It was a 2-valve pushrod engine design, a rarity for the company.
All K series are non-crossflow engines — the inlet and exhaust manifolds are on the same side. They have cast iron blocks and aluminium alloy heads, with a crankshaft supported by 5 main bearings. With the exception of the 5K, all K engines have solid lifters and 1.5 ratio rockers with an adjustment thread for tappet clearance.

Toyota Unser in Malaysia is the latest K-series in Toyota. The 1.8 L (1812 cc) 7K was produced in 1983. Cylinder bore was 80.5 mm (3.17 in) and stroke was 87.5 mm (3.44 in). Output was 76 hp (57 kW) at 4600 RPM and 103 ft·lbf (139 N·m) at 2800 Was available with a 5 speed manual & 4 speed automatic transmission.

The 7K was the final revision of the Toyota K series engine before it was dropped from production in 2002. Boasting 1800cc and plenty of torque, this was an engine designed for and destined to be used in Toyota's Commercial series mini-vans. These can be found by searching for any later model Toyota Vans whose chassis codes begin with KR4xxxxxx

Essentially the 7K block was just a revised 5K (1500cc) design with identical piston width and specs? but the 7K was "stroked" ~300cc larger overall. This meant an engine with plenty of torque (pulling power) but not intended for huge revs or racing.

There was also a 7K-C (Carburettor) version earlier on, with the main difference being crank diameter was a couple of millimeters larger in the EFI engines to handle the higher torque. Also there are some holes in the 7K-E head that don't exist in any of the other K engines.

With a bonus for people with KExx chassis id'd cars, these engines are a much more straight forward "bolt-in" option (compared with Twin cam installations) with the promise of Bigger Torque, Bigger Power and the best benefit of EFI !

The 7K-E inlet setup features a much shorter and efficient runner design than the 4K-E did.


topek said...

at malaysia.. where place can i get this engine??

Goh Kong Chee said...

I think if you go to find the "Kedai Kereta Potong" in Malaysia, they should have this item in store.

eiza1984 said...

i have a question about my unser 2003...using 7K- E engine with EFI. what is suitable turbo system could fit on it? do you have any suggestion about it..thanks

Goh san said...

I can't recommend any Turbo System for your 7K engine as I'm not in the technical field, we are just selling parts.

Just in my very own opinion, the designer of one engine will design the engine as such the performance is in its best suitable condition, any modification that resulting higher pressure or temperature force to the engine, like install additional Turbo system, will sure harm the engine in some way.

Moh Kiki said...

Can i use 7k metal head gasket and put it on my 5k engine?i hope it will fit in bcus the carbon gasket wont last longer as it burned easily

Goh san said...

Yes, you may use the 7K metal head gasket on the 5K engine, 7K cylinder bore diameter is slightly larger than the 5K engine.

Moh Kiki said...

Thx for the instant reply there's no modifications needed la if i wanna put the 7k metal head gasket on my 5k..the extra 3 nut on 7k head wont "kacau" the gasket bro?

Goh san said...

Actually if you find extra 3 nuts you may ask the technical person on this, may I know where you get the 7K metal head gasket?