GSX400 turbo-project

[JJSalo]

Just joined this amazing forum with a lot of experience and expertise, I think. However, there is not so much discussion about smaller Suzys.

I own a dl1000, but bought also a gxr400 twin to use it with a sidecar. For my surprise the gxr has just 20 kw - german-version engine.  The only difference with a full-power version are the camshafts. But those full-power cams seem very hard to find. So, I decided to take a challenge and try boost the bike with a turbo.

I dont want to spend piles of money to this uncertain project and I am going to do most of the job by myself. However, I appreciate advice that I may get from this forum.

This is the plan for blow through system

1. Small-size turbo of a small car

2. Intank fuel pump

3. Inline fuel pressure regulator

4. Stock airbox (will it stand the pressurised air temperature and pressure?)

5. 5 degrees? smaller advance of the ignition

6. Use of alchohol mixed E85 gas

I am also considering of building pressurised extra-fuel injectors to intake manifold to help cold-starts and to prevent detonation when charging the engine hard. I dont have much experience of injection-systems, but a simple push-the button-for-extra-fuel -system may work?

What I allready got is a Borg Warner kp35 turbo clone that is used for example in smaller Renaults and Fiats. It is vety compact, light (just 3,7 kgs), and the inlets and outlets are in suitable positions. It should give enough air to make 50-60 hp.

If somebody has built somerhing like this, I would appreciate sharing experienses.

 

[clivegto]

You need a plenum instead of a air box & it needs bolting on to stop it blowing of. My turbo bikes usually start with no choke at all unless it's very cold. Have a read through this section & others most the information you need has already been covered. 

I built a sidecar as well, but used a 1200 bandit to drag it around. 

[vizman]

2 hours ago, JJSalo said:

 However, there is not so much discussion about smaller Suzys.

 

 

That’s because if you RTFR this site is mainly for big air cooled and oil cooled suzukis....

 

.....a lot of effort to piss against the wind, good luck non the less

[JJSalo]

I was not able to edit the opening of this topic. Anyway, the bike I am dealing with is Suzuki  GSX400 E model 1985. Air-cooled, two cylinders, 4 valves/cylinder, 6-speed, anti-dive system etc. When I bought it, I was astonished because of the very nice and smooth idling, but a proper test-drive was not possible then. Only later, when riding on the road I noticed the lack of power. The "easy" cams make the engine sound smooth and quiet, but when opening the throttle not much happens.

On the other hand, I assume that the easy-timed cams may be even an advantage when speaking about turbocharging?

[Fazz711]

Good luck with your project. 

Hand grenade springs to mind. 

[JJSalo]

May be a grenade. An option for me was to attach a turbo to my Gurls blouse Cx that has a reputation as an ever-mover and also heritage one of the first blower attained cycles. After a while of thinking the result was that after spending together over 80000 kms on the road, it had been an insult to attach any kind of implants on her.

Back to business:

I suppose that using E85 gives cooler burning and the risk of detonation is smaller. For example Saab produced a lot more power from its charged engines by using E85 that stands more pressure without detonation. The problem is though, to get enough vaporised fuel to the cold engine, thats why I wonder if would be a food idea to use manual-controled injection for extra-fuel?

[clivegto]

No, not in my opinion. 

[Gixer1460]

16 hours ago, JJSalo said:

 I assume that the easy-timed cams may be even an advantage when speaking about turbocharging?

They are likely not soft in terms of timing but in lift! If a turbo engine has low lift cams you will have to use more boost to get required mixture in - more boost means more heat and potentially more problems!

43 minutes ago, JJSalo said:

I suppose that using E85 gives cooler burning and the risk of detonation is smaller. For example Saab produced a lot more power from its charged engines by using E85 that stands more pressure without detonation. The problem is though, to get enough vaporised fuel to the cold engine, thats why I wonder if would be a food idea to use manual-controlled injection for extra-fuel?

What the hell does 'manual controlled injection' mean? Some sort of hand cranked pressure pump? Personally I wouldn't use E85 without EFI to meter the fuel - the stuff eats plastics and rubber in carbs that aren't ethanol safe and finding a carb/s able to cope with the wildly varying airflows / pressures from a turbo install will be difficult. Not to mention finding a small enough turbo that won't be laggy as hell with only 400cc to drive it - even a GT15 will likely be too big!

Its - I think - a foolhardy mission and a potential money pit! If the bike is low powered - sell it and buy something with more!

[JJSalo]

Thanks a lot for encouraging! Manual control means a button that gives a signal to injectors to release pressurised fuel to the intake maniifolds. The lift of the valves is not lower compared to the full-povered version, but the timing is not. I  allready have enough bikes, dont need more, my aim is to piss against the wind of wishdom and try something new.

[vizman]

Well I hope you like stinking of piss

[JJSalo]

11 hours ago, vizman said:

Well I hope you like stinking of piss

After 45 years on bikes, I am afraid the odour of my piss is like gasoline.

The size and the type of a turbo for a certain type of a bike is not easy to estimate, but there are some common facts that may help, I think. If specs, dimensions, and other facts are available, then the estimation should be not so hard. When dealing with the turbos of cars, those facts may not be easily found. Nevertheless, some information is available allways:

Water- or oilcooling. This is vety simple. If your bike is watercooled, both will fit, if it is aircooled, be sure that the turbo does not need water circulation.

Dimensions and ports. There is a huge variation. Also the weight is important when you are hanging the blower somewhere infront of cylinders or under the saddle, your ass is also in the dangerous area! The plumbing is easier if the ports and pipes are originally showing in suitable directions.

Then the difficult aspect: Capacity of the turbo. When  fuel is burned, it produces certain amount of gases. In my case, GSX400 consumes about 4 l/100 km and I was looking for a car with around the same consumption, what was not so easy when speaking about turbo-charged automobiles. Also the primary goal, increased power, counts. My goal is around 50-60 hp which should be achieved easily with a small charger designed for a car. No matter of the number of the cylinders, if it is two or more. This has been proven scientificly.

All above is still just theory. The thing that I am worried with the GSX400 is, if it will take the boost without breaking apart. I consider, I learnt my lessons years ago after several craters and holes in the pistons lf my bikes, but i am not sure yet.

My mother tongue is not English and all the stupidities are results of that fact. Readers have all of the responsibility by themselves ;-)

[vizman]

Most of what you said is a mix of nonsense and stating the obvious.

[clivegto]

Water cooled car turbo's don't need water cooling when hanging of the front of a bike in the open air. 

[Gixer1460]

46 minutes ago, clivegto said:

Water cooled car turbo's don't need water cooling when hanging of the front of a bike in the open air. 

Or hung anywhere actually!

[Reinhoud]

The VF20 is a pretty small (ball bearing) turbo, primairy turbo from a Subaru Leagacy.

Edited November 17, 2020 by Reinhoud

[vizman]

Vf20 will be too big for a 400 twin

[Reinhoud]

8 minutes ago, vizman said:

Vf20 will be too big for a 400 twin

You reckon? It's pretty small, the exhaust turbine is small.

What kind of car would have a smaller?

[vizman]

A shit one.

[vizman]

I had a legacy turbo on my blandit engined chop

[vizman]

2 minutes ago, vizman said:

I had a legacy turbo on my blandit engined chop

Actually, I think it was a forester one.....was long ago from a scrap yard far far away

[yantosh]

might have been VF20's from a forester loopy fitted to my slabby, still got a pair on the shelf 

[Gixer1460]

The turbo from a Smart car may work but even that is for an engine at least 50% larger than the OP is using! And regarding the VF20's, I personally wouldn't fit a BB turbo to an aircooled engine without some form of liquid cooling!

[Blubber]

The new fiat 500 has a 900cc aircooled twin and a turbo. Dont know about the rev range of the fiat but it might work out on the motorcycle of the topic starter?

[vizman]

[MeanBean49]

6 hours ago, Gixer1460 said:

The turbo from a Smart car may work but even that is for an engine at least 50% larger than the OP is using! And regarding the VF20's, I personally wouldn't fit a BB turbo to an aircooled engine without some form of liquid cooling!

Been working fine on mine for 6 years