Home built turbo etec 850

[Charlie98765]

I'm looking for some insight into a problem I am having. I turboed my 2017 850 my self it's running great up till about 3/4 throttle wide open it bogs at any speed. It has a garret gt2554r Power Commander 5 PTI with auto tune and stock clutching ( the clutch kit is next)

 

[kingcat162]

02 sensor and afr gauge?

 

[maxwell]

i know my turbo didnt run worth a crap with the stock clutching. Similar to yours it fell on its face as soon as it started spooling. As strange as it may sound these things need load to operate properly. Not saying this is forsure your problem but i think you need to have the correct clutching installed prior to testing to elimate that.

 

[knh208]

i know my turbo didnt run worth a crap with the stock clutching. Similar to yours it fell on its face as soon as it started spooling. As strange as it may sound these things need load to operate properly. Not saying this is forsure your problem but i think you need to have the correct clutching installed prior to testing to elimate that.

Totally agree. It's a system. If you don't have everything right, it won't work.

I suspect the clutching is overloading it and it can't pull through it to spool up the turbo.

 

[Charlie98765]

It pulls really hard at half throttle as the boost comes in but from a strat or when moving if I go WOT it sputters and wont rev up. From a stop if I move the throttle quickly to half it launches had builds boost quick revs high

 

[1709]

I say it`s your fueling, box it not set right or wrong tune in it for 3/4 to wide open, that`s why you can not beat the factory turbo, put gas in it and ride.
that`s been the problem with turbos in the past, is the right tune for all throttle positions, and transition into boost, that`s why it easier to tune if you run low boost, 4 to 6 pounds.

 

[kingcat162]

Get an 02 bung welded into the pipe and put an afr gauge on it - only if you can manually adjust your mapping - if not get a redline box on it - it sounds like mapping to me - I had the same issue on my 800 - my mapping had too much fuel coming on before boost

 

[drew562]

Clutching is so weak the over rev anticipation is kicking in. ??

 

[kingcat162]

Mntnk tried the Dyno jet box on the 850 turbo Doo - they gave up and scrapped it

 

[Longhairfreak]

Try a reverse angle helix. You need to start shallow and get steeper as the boost comes on.

 

[Charlie98765]

I'm thinking of trying Redline Performance tuner selling this Powercommander

 

[drew562]

I'm thinking of trying Redline Performance tuner selling this Powercommander

Power Commanders are junk. Everyone I know with tuning issues took off a pc5 And tried anything else. I’ve always had a boondocker box myself. Takes time to learn. But Way better.

 

[Longhairfreak]

Don't try anything until you clutch for the turbo. The turbo will not produce boost until you have load.

 

[maxwell]

Don't try anything until you clutch for the turbo. The turbo will not produce boost until you have load.

For once, I agree with you

 

[Longhairfreak]

For once, I agree with you

I know more than you know LOL.

 

[oler1234]

I'm thinking of trying Redline Performance tuner selling this Powercommander

Power Commanders are junk. Everyone I know with tuning issues took off a pc5 And tried anything else. I’ve always had a boondocker box myself. Takes time to learn. But Way better.

running a power commander 5 on my home built etec 800 without problems

your problems are 2 fold.

firs the etec are highly sensitive to over fuelling. Especially the bottom end and mid range. Anything above 7000rpm, just make sure it’s rich. You will need to program a base map in for the boost section. Do not add fuel in a non-boost situation, doing so will create crazy amounts of turbo lag. The auto tune can only do so much, it only corrects off the base map. If you stray off the base map to far it won’t correct for it. Get a afr gauge on the sled.

generally speaking

Idle to 5000rpm - 17afr light throttle
5000-6000 - 14afr
600-6500 - 13-14
6500-7000 - 12.5-13
7000 and above 12.5 or greater

it sounds really off but mine runs the best and shifts the clutches the hardest at 10.5afr. This is ridiculously rich but it pull ways hard than 11.5 or 12.5.

that said your stock fuel system will support up to 5psi as low as 3000ft.

clutching is a big deal as well. You could be at the limits of your setup. Complete the old line marker test and see we’re shift out is at first

onr other thing to note is your boost sensor placement will also have a effect on performance. If you think it’s a problem just explain where it’s positioned.

 

[Charlie98765]

It was my ECM welding near it with high frequency tig must have fried it. I ditched to powercomander and got the Silber flash sled runs awesome now. One big problem with the powercomander on the 850 is it only add or subtract fuel from the two injectors in the throttle bodies it has no control over the main injectors