Max EBP before needing a wastegate

[WoodBoy]

Your valves are controlled by your cam so the springs dont matter they just help them close faster pretty much. You could probably get a tune with a little more timing and help with your BP. You should be making some really good power with the 275

 

[B585Ford]

I agree that air and fuel are what causes high EBP, but unless I was mis-interpretting what Newstroker was saying (this was my question anyways), he wasn't asking if the stiffer valve springs cause more EBP themselves, but rather when he gets very high EBP whereas factory valve springs would not completely seal (when closed - I thought their rating was somewhere around 70 PSI) on the exhaust valves because the EBP was overcoming the valve spring ability to close the valve (i.e., he was getting slight valve float from the high EBPs), his stronger springs completely eliminate ANY valve float causing EBPs to be a little higer than it would have been because no exhaust gases were leaking back into the cylinder. I suspect that even if the valve float slightly reduce EBP, the effect would be pretty minimal. I know I don't ever want valve float so valve float would not be a desired method of controlling EBP (if that is possible)...just thought it was an interesting question.

 

[WoodBoy]

I highly doubt there is that much difference and 70psi is a good rule of thumb to go by and not let your EBP exceed on stock valvetrain. Im sure the stock valves will hold a maybe a little more than that, depending on their wear.

OP, you are really not seeing that bad of EBP since you are only seeing around 69-70 and pushing around 58lbs of boost. Im sure wastegatting wouldnt be a bad idea, but I dont think you have just gotten your EBP out of hand

 

[Newstroker]

Your valves are controlled by your cam so the springs dont matter they just help them close faster pretty much. You could probably get a tune with a little more timing and help with your BP. You should be making some really good power with the 275

Yes sir, I am impressed with the truck. I cannot roll into the throttle less than 30mph with out destroying my tires. It gets up to triple digits very quick for a big truck. For what is done I am very happy . I love the way my trans feels with the spartan 275 tune...the shifts are firm and crisp. I am not sure if I will load the 310 or not since I am still on a stock trans.

 

[Ipkyss]

Are you running the latest update tunes? I think the last update was about a year ago? Boost and ebp were reduced in the last update. On my truck at least. I was at one point seeing 60+ psi boost and 70+(70+14=84)EBP with the 310 on stock turbos. I am now down to what seems to be 50-53 psi boost regaurdless of the tune with the 71mm.

 

[Newstroker]

Yes sir, I just downloaded them 2 weeks ago. Good idea though.

 

[B585Ford]

Hate to derail but what air intake are you running?

 

[Jeff@Spartan]

EBP is higher because of the fuel. I saw no real increase on my truck going from the stock atmospheric turbo to the Elite 71mm. Just higher boost at the same back pressure numbers. I would do a wastegate since you have injectors....just for precautionary reasons.