max boost on my setup?!?!?!?

[The_Baldman]

I have a 97 gst. I am installing a 50 trim with stage 3 wheel. What is the max boost I can run. First, here is a list of my mods. Also, I use 93 octane and higher all the time. Walbro 255, 550cc, ramchargers translator w/3.5" lt1 mas, Trust fmic 12x24x3.5, Turbonetics t3t4 50 trim w/stage 3 wheel, 3" turbo back exhaust, ported oem ex manifold, race prep head. Stock bottom end.
Any help will be appreciated.

 

[Lunch_Box]

I think the injectors are going to be what will end up holding you back. Do you have any way on monitoring knock? People have run 20+ psi on pump with a 50 trim but if you have no way telling what is going on inside your engine you wont be able to take advantage on that power.

 

[Rick4g63]

720cc injectors and a Apexi S-AFC can help with fuel management issue.
Air fuel ratio and ignition timing will be a major factor at that boost level.

 

[sweet97]

Biggest problem with my 50 trim is not the 550's I am running but the stock` sidemount. You still need toknoe what's going on and I recommend the fullthrottle "Scanmaster" Mark

 

[Rick4g63]

The smic is a limiting factor in the performance of the 50 trim but proper fuel management will play a major part in the extracting power from that size turbo.

The duty cycle of a 550cc injector can be "maxed out" at "little" as 16 psi.

 

[Awdboost]

You could run as much boost as you want.. If you had control over your timing. The higher in boost you go the less timing you need to have. The trick is to stay away from too much Cylinder pressure and Detionation.. And the two are very related. I ran C16 on my stock 7-bolt with cams, stock intake man, ARP. 11.54 @ 128 and 29-32 psi on my FP3065. Watch thous head studs thou. The trick is to get your turbo up to it's efficancy.

Mind the spelling error and Grammer.. Long day

 

[sweet97]

I will check the duty cycle of my 550's and 50 trim with the scamaster as that is one of it's features. I can run the 550cc's a bit higher as far as fuel supply goes but the sidemount gives out first. I am going with the 720cc injectors and a Dejon streetmount IC with a goal of 18 PSI. With that mod list adding the 720's and some form of fuel control will probably allow 20 PSI on pump. I have a wideband and the GM MAF-Translator. Those and the scanmaster are my tools for fuel control. Mark

 

[Black95TSIawd]

an afc isnt too accurate when your pushing 700cc injectors are larger. 680's will probably suffice for you with an afc.

 

[sweet97]

What do you mean? Air fuel controller? 550's were perfect with my EVO and as far as I can tell the 50 trim will flow 30% more air at the same PSI as a big 16G. There are many guys saying 660/680's are the best for the EVO and a few running the same with their 50 trims. There's only a 4.5% difference between 680's and 710's.
I have plenty of time to be sure of my decision as the car goes into storage at the end of the month. Mark

 

[sweet97]

OK I checked out my duty cycle with 550cc injectors and a 50 trim on a 1g with a stock sidemount IC & 13 PSI. The A/F was an 11.xx:1 and the duty cycle was 90% which I consider too kigh. I believe an 80% duty cycle is best from info from RC Engineering. I am even more sure I will be going with 720cc injectors. Mark