Upgrading Bender stage 2 GT2554r to GT2560r front mounted

[Jabakanada]

Fuel is European 98 or USA 94.

 

[rxrider]

Jabakanada - You can run 16 with 3 stacked head gaskets but I recommend you remove the cams and retork the stock head studs to max 51Nm it's about all they can take. In the correct sequence loosen one nut at the time a 1/4 turn and tighten it back to 51Nm in one movement. For the best result; remove one nut and washer at the time in the correct sequence and apply moly lube/grease on both sides of the washers and on the contact surface of the nut, also apply moly lube on the nut threads. Tighten to 50Nm, 1/4 back and retork to 51Nm.

Your AFRs are still a bit high at WOT. Idle should be 14.5 approx, engagement shoud be 13.5. I would say your pretty close both at engagement and up to 1/2 throttle. WOT and idle would take a bit more of tuning.

Another tips is to check and adjust valve clearances while you have the cylinder head cover off. You would be amazed how far off some of them are, with every one that is out of spec performance suffers

 

[Jabakanada]

Jabakanada - You can run 16 with 3 stacked head gaskets but I recommend you remove the cams and retork the stock head studs to max 51Nm it's about all they can take. In the correct sequence loosen one nut at the time a 1/4 turn and tighten it back to 51Nm in one movement. For the best result; remove one nut and washer at the time in the correct sequence and apply moly lube/grease on both sides of the washers and on the contact surface of the nut, also apply moly lube on the nut threads. Tighten to 50Nm, 1/4 back and retork to 51Nm.

Your AFRs are still a bit high at WOT. Idle should be 14.5 approx, engagement shoud be 13.5. I would say your pretty close both at engagement and up to 1/2 throttle. WOT and idle would take a bit more of tuning.

Another tips is to check and adjust valve clearances while you have the cylinder head cover off. You would be amazed how far off some of them are, with every one that is out of spec performance suffers

I have allready torked head studs to 50Nm and did it with loosing 1/4 round and then re-torked them to 52Nm.

Are you sure that those 3 stacked gaskets and stock studs will hold 16psi of boost?

Another thing to worry about is oil consumption... my sled is -04 and it takes about 1,2 litre (0.317 006 462 83 gallon) oil in 1000km (620 miles). Should I re-ring the motor with -05 piston rings?

 

[rxrider]

Mine is taking about 1 litre every 1000 km. I don't worry about it, I run Wiseco 10:1 pistons and rings, still leaking like it did with the stock pistons and rings. Re-ring to 05 may help. What is your compression? If compression is good I would not care to change out the rings. There's a possibility that oil is not going past the rings, but out the turbo, thru the valve train. Torked to 52Nm I would not worry too much about the head gaskets. If you detonate the gaskets may go, but use the best pump fuel you can get. I don't know where you gas is coming from. If it's from a Shell refinery it should be as good as it gets.

 

[Jabakanada]

Ok. Compression is good and equal between all four cylinders. Sled starts good and runs good. I am not worried about quality of fuel here in Finland. Sounds that I could just throw my new-used GT2560r to its place and adjust wastegate to 16psi of boost.

I think that AFR must be veeeery close to perfect when boosting up to 16 with stock pistons and rods?

 

[rxrider]

With 3 head gaskets and stock pistons I would not run more than 14 psi. Your compression will be at 9.4:1 - running 16 psi will be on the edge of disaster, you need to be at 9.1:1 to run safe at 16 psi of boost.

 

[Jabakanada]

With 3 head gaskets and stock pistons I would not run more than 14 psi. Your compression will be at 9.4:1 - running 16 psi will be on the edge of disaster, you need to be at 9.1:1 to run safe at 16 psi of boost.

Yep. I just ordered APE Yamaha R1 heavy duty head studs and 1,5mm stainless steel head shim. What do rxrider think...... one split head gasket or two head gaskets?

 

[rxrider]

You can split it and replace the mid flat section of the 3-layered head gasket with the new head shim you have on order. What thickness is the head shim? If you have the thickness of the head shim I could do the calculations for you to find the CR-combustion ratio.

 

[Jabakanada]

You can split it and replace the mid flat section of the 3-layered head gasket with the new head shim you have on order. What thickness is the head shim? If you have the thickness of the head shim I could do the calculations for you to find the CR-combustion ratio.

Thickness is 1,5mm

 

[rxrider]

According to my calculations running the head shim and 1 split gasket your CR will be at 9.73:1, running at 98 octane pumpfuel will be safe up to max 14 lbs or 0.95 BAR.

If you run two gaskets with the shim in between your CR will be at 8.68:1, you can run up to max 17.5 lbs or 1.2 BAR.

These recommendations are given as is, other settings in your sled would also play a part in how high boost pressure you can get away with, no garantees given

 

[rxrider]

Running an AFR system and a Boost meter is mandatory... do never run without knowing what your fuel and boost is at.

 

[Jabakanada]

Thanks rxrider.

I have boost, fuel press and AEM AFR -gauges. It will be either 2 gaskets + shim or 1 gasket + shim + 1/3 gasket (=other gasket surface and without center layer). I am still considering to go lower pistons but there is still some time to plan things for next season.

Are you using that boost calculator which is sticky on this turbos/supercharger area? I didn´t got similar numbers with it. What is the thickness you use for OEM gasket, 0,027"?

 

[rxrider]

That setup will give you a CR of 9.17:1 max boost is 16 lbs or 1.1 BAR.

PM me your emailaddress and I'll send you my version of the boost calc, it's modified for our fuel.

The tickness of the stock gasket is 0.027" compressed. Thickness of head shim is 0.059".

 

[Jabakanada]

Yeah, now I´m going to front mount... or mid mount with GT2560r. I am putting Rev gas-tank and maybe rev seat. Any tips for project?

Header will be garage-made. What should be inner dia of header pipes?

Tunnel modifications first.

 

[rxrider]

You could always read my rxrider's turbo garage thread, link in my sig, a lot of relevant info in there.

Header pipes inner diameter should be at least the size of the exhaust outlets.