How to get 400bhp from a YB ?

[mrjimbo]

What is the best way to get 400-420 bhp from YB turbo motor. What cams and turbo etc

[BigErn]

400 bhp can be squeezed from a standard motor on T34.63 and greys. A mate was seeing 420ish from his Ahmed mapped T38 and light blues on a standard engine. After owning a few YB's of various spec I think the T34.63 on 55's and an AB07 inlet cam properly mapped would make a great fast road car.

[mrjimbo]

AB07 inlet cam and standard exhaust cam or change the exhaust cam for something elsewhile were at it ?

[Graham]

400 plus bhp is rather beyond the scope of a t34, it will be spinning its nuts off and last all of about 10 mins

[mrjimbo]

So the T34 is not quite up to the job, what would be a good starting point for the turbo and cams ? as i'm new to all this turbocharging malarchy i need all the help i can get with this one.

[mrjimbo]

Would a BD10 inlet cam with a BD14 exhaust cam and a better turbo be a step in the right direction

[BigErn]

No, on a turbo'd YB motor its the inlet side they struggle on really. A standard exhaust cam can be used up to around the 500bhp mark. A BD14 inlet can be ran on standard non pocketed pistons with the correct timing but personally I wouldnt do it as it brings the valves and pistons too close for comfort. The AB07 inlet is the best choice for standard pistons. The T34 will indeed be running a short life at that kind of power, I ran mine at 36psi and it only lasted around 12k miles. The best option for the YB really is to decide if you would rather 380 or 420 bhp as both figures are more easily specced than 400bhp.

What is your current engine spec??

[mrjimbo]

We have a good clean standard tall engine (block, pistons,rods sump etc virgin head in good clean condition and standard cams) which was bought to go N/A but ran out of money so i sold it to mate at work who wants to build it up turbo powered. We have since aquired 2wd exhaust manifold, inlet plenum fuel rail throttle body and a set of Greys.

[costina]

T38 siemens 83lb injectors AB07 inlet ported head will see around 430ish bhp a guy on passion seen over 500 with a very similar spec.

[Cosnada]

I have a totally stock 4x4 200 block engine etc. I have gone for 400bhp. My spec:
Running late Sierra green top 4x4 engine.
Completely standard - no head work or cams etc.
Full lambda control fitted as factory standard.
Running standard Weber Marelli L8 ECU with standard Ford ECU loom.
MSD (Motorsport Developments Blackpool) 380bhp Evolution chip. Chip was written for spec detailed here. I also had CLOSED LOOP enabled on the chip.
Iveco truck intercooler.
Garrett T34/.63 turbo - fully rebuilt.
-31 actuator.
Grey 403 injectors (pintle caps trimmed).
3 bar map sensor.
K&N Group A air filter.
Standard Amal valve boost control.
3" Stainless open exhaust.
044 Pump.

Cheers.

Hows the lathe

[mrjimbo]

Hi matey, The lathe's doing well, not used it for a while though. I have a standard 2wd block and head assembly and have been picking up bits here and there. So far managed to get hold of 2wd exhaust manifold and inlet plenum fuel rail and some Greys and a pair of cams(BD10 + BD14) still need lots of bits to complete but don't want to go buying things that wont be any use to me. i'm new to all this turbo malarchy so need all the help i can get.

[Clint]

Hey Jimbo,

400BHP is one of them power figures that trip into expense, 350 is really easy and cheap 400 needs a decent turbo, quite often the 350BHP engine will be much better than the 400 if not done right as the average torque is higher.

What are you going to be using the car for mainly last time we spoke you were sprinting wasn't you ?

[mrjimbo]

Hi Clint, Sprinting on the back burner at the moment. The turbo engine is for a mate who wants to put into an old BMW back in Poland for use on the road and track days, probably an early 316/318/320. The engine is one that i bought to go N/A in the Escort but money dried up and family problems meant it never got done so i sold to a mate at work, when we stripped it it was like new inside and has a virgin head so he wants to rebuild it turboed and the figure he's looking for is 400hp so were trying to get some ideas as to how to go about it.

[Clint]

Shame about the sprinting m8, good to see your still in the scene

Well its all down to the turbo really, a proper T34 (Esc Cosworth with 0.63 rear housing) will just do it maybe a bit shy on Polish fuel (inconsistent right?). A newer style GTX30 would reach it easily on low boost but would have a poor low end spool up penalty. Either turbo new will cost circa £1100 a big investment.

Whatever I would aim for 7.8:1 as you will need to put some valve pockets in your pistons, fit them with a new set of Mahle rings - Ported head is almost a must as is a 2wd exhaust manifold and a 4wd inlet plenum and fuel rail, if you want to use your new cams put the BD14 in the inlet and the 10 in the Exhaust time both to 110 degrees.

You will need greys 0280150403 as a min on the T34 and/or some bigger 70lb injectors (low imp) from the states if using the GT turbo (importing the 70lb is probably cheaper than buying greys new) I just got 8 for £70 each landed a piece.

Use a proper Group A head gasket and a set of ARP stud and nuts (make sure your follow the ARP instructions).

Give me a txt if you need any info quick.

Clint

[mrjimbo]

Cheers Clint are you still on the same mobile number ? the engine will be built as and when funds allow' just don't wnt to go buying stuff that's not going to be of much use.
What's the difference between the 2wd and 4wd plenum and fuel rail ?

[Clint]

What's the difference between the 2wd and 4wd plenum and fuel rail ?

Flows better (about 6%) and is safer as the regulator bolts to the rail.

[mrjimbo]

Ok

[mrjimbo]

Are the grooves on the inlert cam bearing journals there for a reason ? the exhaust cam bearing journals don't have these grooves

[BigErn]

Due to the way the oil is fed into the YB head the inlet cam needs the groove and the exhuast does not.

[Clint]

Are the grooves on the inlert cam bearing journals there for a reason ? the exhaust cam bearing journals don't have these grooves

The only reason is for identification on assembly, you can use either cam in inlet or exhaust, however the timing marks are 180 degrees out, so use your preferred method of timing cams (lift@TDC, or all in @ degrees) instead of the timing marks.

There is no difference in oilways.

[mrjimbo]

So i don't need to get the grooves machined in to the journals then if using an exhaust cam in the inlet side is that right ?

[Clint]

So i don't need to get the grooves machined in to the journals then if using an exhaust cam in the inlet side is that right ?

No either cam will work in either side without ANY mods they will just be 180 degrees out of rotation.