B-12(16)T

[rerb]

On 6/21/2021 at 2:39 PM, Chadillac said:

What jets are you running?

[Chadillac]

[IhmeJanneFIN]

Hi all, i thought of starting a new thread, but I may just ask this here.

Been reading through different 1216cc turbo build threads, and on almost everyone is mentioned gen1 pistons and conrods are the way to go on a budget, but I would like to ask though.

Has anyone used gen2 busa conrods and pistons on 1216cc turbo build with success on about 250-300hp range builds?

I know the gen2 busa pistons and rods are "weaker" as they use 18mm piston pins as opposed to 20mm on gen1 busa pistons. I also know the rods are same length, but gen2 has thinner bolts on the big end and smaller small end to accomodate the gen2 piston.

Also the gen2 busa engine is stroked +2 mm from gen1, but block height is the same on both as they can be swapped around. I looked through Wössners catalog and the pistons compression height differs.

Both pistons are 13.5:1 compression ratio;

Gen1 compression height: 25,25mm

Gen2 compression height: 24,00mm

So there seems to be 1,25mm difference in compression height to make room in the busa to add 2mm of stroke in the same available space?

Hypotetically thinking, would this mean, that using gen2 busa parts on a 1216cc build, there wouldn't be need for as thick spacer under the block as opposed to using gen1 busa parts?

I am asking as gen1 busa parts are highly sought after, so are beginning to be hard to find and costly. But gen2 busa pistons and rods are plenty to find and cheap relative to gen1 parts.

I ask, because I have acquired myself an 1992 Gsxr 1100 engine recently, so there might be a 1216cc turbo build on the horizon...

One idea is also to use gen2 pistons if they are good for boost, but use ie. maxpeeding gen2 busa rods with upgraded bolts.

 

[DAZ]

14 minutes ago, IhmeJanneFIN said:

Hi all, i thought of starting a new thread, but I may just ask this here.

Been reading through different 1216cc turbo build threads, and on almost everyone is mentioned gen1 pistons and conrods are the way to go on a budget, but I would like to ask though.

Has anyone used gen2 busa conrods and pistons on 1216cc turbo build with success on about 250-300hp range builds?

I know the gen2 busa pistons and rods are "weaker" as they use 18mm piston pins as opposed to 20mm on gen1 busa pistons. I also know the rods are same length, but gen2 has thinner bolts on the big end and smaller small end to accomodate the gen2 piston.

Also the gen2 busa engine is stroked +2 mm from gen1, but block height is the same on both as they can be swapped around. I looked through Wössners catalog and the pistons compression height differs.

Both pistons are 13.5:1 compression ratio;

Gen1 compression height: 25,25mm

Gen2 compression height: 24,00mm

So there seems to be 1,25mm difference in compression height to make room in the busa to add 2mm of stroke in the same available space?

Hypotetically thinking, would this mean, that using gen2 busa parts on a 1216cc build, there wouldn't be need for as thick spacer under the block as opposed to using gen1 busa parts?

I am asking as gen1 busa parts are highly sought after, so are beginning to be hard to find and costly. But gen2 busa pistons and rods are plenty to find and cheap relative to gen1 parts.

I ask, because I have acquired myself an 1992 Gsxr 1100 engine recently, so there might be a 1216cc turbo build on the horizon...

One idea is also to use gen2 pistons if they are good for boost, but use ie. maxpeeding gen2 busa rods with upgraded bolts.

 

Ooh will this possibly reside in your fabulous gsxf ......I do hope so  it would be an utterly bonkers sleeper

[IhmeJanneFIN]

1 hour ago, DAZ said:

Ooh will this possibly reside in your fabulous gsxf ......I do hope so  it would be an utterly bonkers sleeper

That is the idea at the moment, but it may be sometime before that may happen. Also on my gsxf sleeper build, space is a luxury (only few mm on turbo cold side to fairings), so there is only barely room for current turbo, let alone to a bigger one capable to around 300hp. Current on is GT2052 of a diesel merc, so quite small and smaller than usual GT2052 AR numbers, so very quick to spool, but might be a bit restrictive on high rpm. But hey, it's a streed build so I like the low spool. It is barely run at high rpm and it's got an 40mm external wastegate, so exhaust pressure isn't a problem what I have measured pre turbo exhaust pressure.

Edited March 13, 2023 by IhmeJanneFIN
typo corrections

[DAZ]

6 hours ago, IhmeJanneFIN said:

That is the idea at the moment, but it may be sometime before that may happen. Also on my gsxf sleeper build, space is a luxury (only few mm on turbo cold side to fairings), so there is only barely room for current turbo, let alone to a bigger one capable to around 300hp. Current on is GT2052 of a diesel merc, so quite small and smaller than usual GT2052 AR numbers, so very quick to spool, but might be a bit restrictive on high rpm. But hey, it's a streed build so I like the low spool. It is barely run at high rpm and it's got an 40mm external wastegate, so exhaust pressure isn't a problem what I have measured pre turbo exhaust pressure.

Thing is the torque will probably be instantaneous ( big twist and go ) and if your not bothered about revving the thing to the moon it may well be just what you want , if it's  to restricted at higher rpm look for another turbo in the same family with bigger wheels,

[DAZ]

@IhmeJanneFIN reading your question regarding the compression height of the pistons and spacers , I think the gen 2 pistons would require less of a spacer as you say, but many on here have or claim 250+ hp with std rods, what would the cost of gen 2 pistons +new rings ( y / n / ?) + maxspeeding rods +spacer plate be vs 1216 mtc 10:1 turbo pistons ? How do you think your turbo would be with that compression ? 

[IhmeJanneFIN]

48 minutes ago, DAZ said:

@IhmeJanneFIN reading your question regarding the compression height of the pistons and spacers , I think the gen 2 pistons would require less of a spacer as you say, but many on here have or claim 250+ hp with std rods, what would the cost of gen 2 pistons +new rings ( y / n / ?) + maxspeeding rods +spacer plate be vs 1216 mtc 10:1 turbo pistons ? How do you think your turbo would be with that compression ? 

Std used gen2 rods and pistons I could find around 250-300€ with postage on flebay. Bare gen2 pistons for around 150€.

Some guy here in Finland is selling unused gen2 pistons with rings for 250€. Has multiple sets to sell.

Maxspeeding rods for gen2 cost around 400€ with postage. About the same for 1100/1200 oil boiler with 20mm piston pin.

New mtc 10:1 turbo pistons with 20mm pin, to get them here in Finland would cost around 800€.

So, by quick math;

Gen2 used parts would cost around 300€ and would be ok for around 250hp?

Gen2 NEW pistons and gen2 maxpeedingrods would be around 650€. Pistons good for around 300hp?? Conrods advertised to be 600-800hp, but I am skeptical of that. Carillos would cost me a liver and an arm, so they are out off the question.

New MTC turbo pistons and oil boiler dedicated maxpeeding conrods would be around 1200€. Would definately be good for 300 hp.

So going busa gen2 parts it would be about half the price, even with beefier maxpeedingrods.

Spacer I can make myself, have done already multiple spacers with my handtools in my garage. Took some time, but managed to make them .

I am bit spectical if the MTC 10:1 compression would be too high and still need to run a spacer plate to lower comp to around 8.5:1. That's what I currently have in my Frankenstein 988cc and it's got good torque off boost. I do have the primary breather valves* on the plenum, so the engine breathes through those valves when not on boost so it definately helps with the off boost driving.

(*The primary breather valves are big 2-stroke reed valves, so when there is vacuum in the engine, it draws air through them and not all the way through turbo and boost piping. But when plenum sees positive pressure they automatically seal closed as in 2-stroke engine. Seem to work great as with my first engine, turbo started to spool around 1000 rpm lower that without the reeds on plenum.)

[IhmeJanneFIN]

10 hours ago, DAZ said:

Thing is the torque will probably be instantaneous ( big twist and go ) and if your not bothered about revving the thing to the moon it may well be just what you want , if it's  to restricted at higher rpm look for another turbo in the same family with bigger wheels,

Well, when driving around 100 km/h 6th gear on highway, it is on the brink of spooling at the moment at 3000rpm. Twist to full throttle and under 1 sec there is full boost on the gauge and off we go.

Turbo is somewhat special as it's from a Mercedes diesel engine with 3 bolt pattern, so there is no bigger version of that specific turbo family that I can found. Only one with the same bolt pattern is GT2256V, also from a diesel merc, but is fysically bigger also and with variable geometry so might melt the vnt system on petrol engine. I am tempted to try as the idea of vnt sounds fun with low spooling and big flow at high rpm.

From my current turbo I may need to build a hybrid with custom wheels but sounds expensive and not worth the money. Been thinking of using some maxpeeding GT2860 or similar. GT2252/GT2256 would possibly be better, but I can find only expensive oem garretts and not cheap aftermarket versions.

As this is a street build, I rather have the low rpm spool as opposed to max power at redline where it cannot never be used on public roads.

[DAZ]

From your description of how your current set up runs you may be at the limit of your current turbo ,it sounds ideal as is ,boosting down at 3000rpm, perfect for a street bike, and your reed valve idea is superb, but I wonder how it will cope with an extra 20/25% capacity. Do you have a turbo reconditioning shop that could advise on a hybrid turbo build? It might be that different Garrett parts maybe suitable . On a separate point,don't forget that the 1127 motor is taller (and a spacer plate will add a bit more) than your 750 based engine, so your plumbing may need tweeking to suit 

[IhmeJanneFIN]

3 hours ago, DAZ said:

From your description of how your current set up runs you may be at the limit of your current turbo ,it sounds ideal as is ,boosting down at 3000rpm, perfect for a street bike, and your reed valve idea is superb, but I wonder how it will cope with an extra 20/25% capacity. Do you have a turbo reconditioning shop that could advise on a hybrid turbo build? It might be that different Garrett parts maybe suitable . On a separate point,don't forget that the 1127 motor is taller (and a spacer plate will add a bit more) than your 750 based engine, so your plumbing may need tweeking to suit 

I am also thinking it will be too small for 1216cc engine. I have two of those reed valves on the back of the plenum an they are quite big. 

I know there is somekind of turboshop in city next to my town, might be worth a visit at somepoint.

My current engine is actually only 5mm lower than a stock 1127 as I have 12mm of spacer under the current 748 block, so not that much will change I hope, but time will tell when I begin the engine build.

[Arttu]

7 hours ago, IhmeJanneFIN said:

Turbo is somewhat special as it's from a Mercedes diesel engine with 3 bolt pattern, so there is no bigger version of that specific turbo family that I can found. Only one with the same bolt pattern is GT2256V, also from a diesel merc, but is fysically bigger also and with variable geometry so might melt the vnt system on petrol engine. I am tempted to try as the idea of vnt sounds fun with low spooling and big flow at high rpm.

I don't think you need to worry about melting the VNT system on bike application. At least mine didn't show any problems after few years in road use. And it probably had pretty high exhaust temps based on how the exhaust valves and ports were looking...

Yes, the VNT can provide some benefits but getting the control system working properly may take some effort. And benefits compared to normal turbos might be smaller than you would expect. Mainly because if you try to make the turbo to spool-up early it results high exhaust pressure and typical bike engine really don't like that, especially at low revs.

[IhmeJanneFIN]

46 minutes ago, Arttu said:

I don't think you need to worryabout melting the VNT system on bike application. At least mine didn't show any problems after few years in road use. And it probably had pretty high exhaust temps based on how the exhaust valves and ports were looking...

Yes, the VNT can provide some benefits but getting the control system working properly may take some effort. And benefits compared to normal turbos might be smaller than you would expect. Mainly because if you try to make the turbo to spool-up early it results high exhaust pressure and typical bike engine really don't like that, especially at low revs.

Good to know Arttu. I have also been thinking smart way to control those vanes and it would involve some type of vane opening system for cruising and idle to not cause high exhaust pressure. Adjusting the vane position to just at the tip of spooling one change, but sounds sketsy. Might give a try on my SV build for vnt turbo, as there is more room for turbo as no side fairings.

 

But before this goes totally offtopic, about my original question of using gen2 busa parts, anyone has any input on that?

[Arttu]

17 minutes ago, IhmeJanneFIN said:

But before this goes totally offtopic, about my original question of using gen2 busa parts, anyone has any input on that?

Only piece of info that I can provide is that stock rods and pistons should be good for at least 300hp. There are quite many gen2 turbo builds around that power range using stock engine internals.

[Gixer1460]

3 hours ago, Arttu said:

Only piece of info that I can provide is that stock rods and pistons should be good for at least 300hp. There are quite many gen2 turbo builds around that power range using stock engine internals.

But most are using management for accurate fueling and timing, both go a way to avoid detonation.

[clivegto]

I've used MK1 busa rods and pistons on 2 turbo engines with spacer plates, 2nd set I had supper finished . The busa MK2 rods fit as well, you just need to do a dry build to see what's what. I reckon they would be good for 300hp+ easy but not done this mod myself yet .

[IhmeJanneFIN]

9 hours ago, Gixer1460 said:

But most are using management for accurate fueling and timing, both go a way to avoid detonation.

Planning on going efi this time around, as I want to try to work that out also. Also dreaming of using E85 as flexfuel setup, as the ecu I am planning, will support it. Speeduino UA4C (Sea Fox) by the way. Very cost effective and is tuned with tunerstudio, same like mega-/microsquirt but is cheaper.

 

8 hours ago, clivegto said:

I've used MK1 busa rods and pistons on 2 turbo engines with spacer plates, 2nd set I had supper finished . The busa MK2 rods fit as well, you just need to do a dry build to see what's what. I reckon they would be good for 300hp+ easy but not done this mod myself yet .

Dry build is a must, did it with my current engine also to work out ie. spacer thickness and valve clearance when timed the stock cams.

Well it seems that if I cannot find mk1 busa parts "cheap enough", I might as well go with the gen2 busa parts and maybe mix it up with rods from maxpeeding. Hopefully I am not aiming to the moon with my power levels, as it seems they should be sufficient strenght at 300ish hp levels. Idea of a around 300hp stock looking, facelifted model gsxf with selfbuild oil boiler sounds just a bit more sweeter than a modern looking superbike bought off the shelf.

[clivegto]

B12 rods are good for 300hp+ can not see MK2 busa one's been weeker.

[Froggyv8]

I built a Saab 2.3 engine with a large Vgt turbo from a dodge ram , no heat issues even at 2 bar 500+ hp . Controlling the vane is the hard bit . Needs to be open on cruise \light throttle then close when boost is requested to spool fast whilst opening back up as pressure and flow rise , a lot use a simple spring to hold the vane closed and let turbine inlet pressure push the vanes open but as soon as you lift and lose pressure the vane shuts you lose a lot of turbine speed as the holset  had a speed sensor .