I want to add BOVs on my Callaway? Can I put two on, one after each turbo before the intercooler?

 

Are you wanting to use them to protect the turbos from the back pressure when you come off the throttle? Or do you just want to hear that freaky sound they make. :thumbs: How much boost are you making? What compression ratio did they use in your motor?

 

im pretty sure u can only put 1 BOV even if it is a twin (dont quote me on this im pretty sure my GTR firends wit Twin say u can only have 1)

 

Both :D Im making 13lbs of boost, 7.5:1 CR.

 

7.5 c.r. wow. You could probalby go to 1 bar, no problem. Porsche friends used to always upgrade wastegate with stiffer spring to increase boost to 14.7lbs and no problems with same compression ratio. Some use to advance the ignition to overcome some of the lag and on a down shift they would throw out some mean flames out of the exhaust. I would suggest, because the way your turbos and intercoolers are laid, out to put them before each intercooler. I have never been in a turbo vette. Much lag? When does boost hit?

 

Well there are a couple of problems with high boost on b2ks. First, Callaway didn't use the best connecting rods in the world, they used the forged chevy "pink" rods. They have been known to break and go thru the block! :eek:

Second if you look at the pic in my sig, you'll see the two supplimental injectors on the rams horn. With two much boost say 15lbs, too much of the fuel ends up at the back of the intake and runs the front cylinders lean. Ive only heard of one b2k running 15+ lbs sucessfully. And the guy has his own dyno and enough money to burn if he kills a short block, I don't ;)

My car is making really good power right now. Remember this car has stock cam, heads. A set of AFR 190s would be absolutely killer on this motor.

As far as lag goes, there is really none, assuming youre in the correct gear. Boost is there at 2100rpm and peaks by 2600-2800. I can't remember right now cause its been well over a month since Ive driven my car. :bb

Back to the original topic, I was thinking a BOV on each compressor pipe below the intercoolers.


[Modified by SurfnSun, 11:55 AM 8/23/2003]

 

I guess your right about the lag part. All the turbo cars I have been the biggest diplacement was 3.6 liters. With 5.7 ltrs the torque will hold you till the boost hits. Must be small turbos to come that soon and peak that early also. If you flow too much air through your heads it sounds like your turbos will run out of air above 55oo rpm. I have never been a fan of supplemental injectors placed so far away from the combustion chamber. You hear of fuel puddling or improper distribution like you are saying. Back to the BOV's. Your talking about putting them in between turbo and intercooler. What pressure would they go off at?

 

The turbos might peak around 3200rpm but no later. Due to the design on the TPI all of these cars are out of breath by 4800rpm. These are the same turbos that powered the Callaway Sledgehammer, 890hp. I do know of a couple of 600+rwhp cars.

Id set the spring as weak as possible for it to still stay closed under full boost.

 

Are you really sure about that Surf?
I dont think they are. The sledgehammer has some TO4B's in there, same ones I have awaiting my plans, and they are fairly large. the sledgehammer has some funky piping going on in it, nothing like a stock B2K. This makes me think the To4B's are a lot larger then the rotomasters compact units (and whatever else callaway used).

if you look closly at this picture, you can see how they are different. I have the magazine these pics came from, and the originals are a lot bigger, so you can see more detail.




The turbos are rotated 90 degrees on the sledgehammer, vs the B2K's.
It always made me wonder whats going on here.
:confused:


[Modified by bill mcdonald, 1:06 AM 8/24/2003]

 

Bill,

My car has T04Bs, unless they are different thatn the ones the Sledge used. I could be wrong about, but I figured since both were T04Bs they were the same.

I wonder if the intake tracks and intercooler placement predicated the shift in the position of the turbos.


[Modified by SurfnSun, 10:03 AM 8/24/2003]

 

T04Bs come in many flavors. (different trim wheels, housings, etc)