Gurus-
I'm tuning WGDC on my FP Green 73HTA to get a smooth boost profile for 4th and 5th gears and keep my stock block intact. I'm on V7, E85 and using PSI targetting for boost control, but stuggling to prevent overshoot and the rapid downward correction that follows.

What target boost levels do you guys recommend from 2500-4000 RPM in 4th an 5th gear to keep the stock block in one piece?

I'm shooting for this but don't know if it's safe or not:
RPM PSI
2500 13.5
3000 15.6
3250 17.7
3500 21.0
3750 25.6
4000 26.7
4250 26.7
4500 26.7

I've attached my WGDC settings below so you can see how I'm trying to smooth the hit in the higher gears. It comes on strong and early with the Green and I really don't feel like venting my block.

Any thoughts or advice you can offer would be appreciated.

 

Have you actually seen those boost numbers at the corresponding RPM's in the table above, or are those just ideal target levels?

 

I ask because 16# by 3000 is not too shabby for a Green. It is spooling nice, especially for a JB Green.

 

Yes Sparky, I've got it spooling good! (see below). I'm really asking ... what is a safe level of boost is to target for 3000-4000 RPM with a stock block.

 

From 21# at 3500 to 26# only 250 RPM later. That is a 5 PSI jump in just 250 RPM. It is hitting way hard in the midrange. This is great if you are aiming to make gobs of lower midrange torque, but not mucho bueno for rod longevity which is what you are worried about if I am reading you correctly. I would say that you don't want to be seeing 25# until 3800 RPM at the earliest if you want it to hold together. You sure have it spooling and it is hitting hard though.

 

Sounds like a good plan Sparky, thanks for your input. I'll see if I can slow it down some more with a much lower WGDC around 3000 to prevent the large downward correction caused by the overshoot at 3250. I'll also lower the WGDC at 3250 and 3500 to try to keep it below 25# at 3800.

 

I hope that you can get some knowledgeable advice on here from peeps that know how to actually tune boost.I wish that I could help you but I don't know anything about ECU tuning or ECU controlled boost. So, I hope that you get someone to answer your questions and thus guide your efforts.

If you were running an VIII, or a IX turbo I wouldn't worry too much. But that HTA Green is capable of installing a window in your block right now if you are not careful. There are a couple guys over in the East Bay that are real capable and have experience at creating safe E85 tunes. I might give FFTEC a call if I were in your shoes. That turbo is a real torque producer.

It is one thing to self tune a stock turbo on 91 octane. It is another ball of wax to do that torque monster on E-85. So, just tread cautiously.

 

Make sure your upward correction table is zero'd out. If not, it will make the boost spike.

Also, your WGDC and Desired boost tables both need more work.

 

Thanks for chipping in Jay. I know they need work, which is why I posted up. I'm ready and able to make the changes but before I do I wanted to ask the community for advice. My upward WGDC correction is zeroed out while I work on this. I've already got the boost and WGDC settings dialled in for gears 1-3. Obviously gears 4 & 5 make serious boost at lower RPM with the Green.

What do you think the "safe" boost targets are for 4th, or 5th gear, at 3000, 3250, 3500, 3750 & 4000 RPM, to keep my stock block in one piece?

For example:- Do you agree with Sparky that boost should be held below 25psi at 3800?

I'm sure you appreciate that this is not something I want to do by trial and error! Thanks for any advice you feel able to give me.

 

Boost has nothing to do with keeping your stock block happy. Its all about torque. Keep the torque under 400-420 (dynojet/VD) and you should be ok.

 

That makes more sense. So something like this torque curve from a 3rd gear pull should prevent catastrophe - no?

 

Any idea how much preload is on the actuator?