Carbed 2 stroke turbo guy's !!!

[DragonFreak]

i took my sled out today and it was running great i checked the plugs and they looked good. Then it started bogging a little bit. When we stopped it shut off and was hard to get to start. Then we road a little and it was running like crap and wouldnt build boost or rev up. We stopped cleaned the plugs up and it fired and ran good for like three powder turns and shut off and wont start. It didnt have strong spark on the hill and now at home it has ok spark but wont start? The comp. is 100 and like 105. Is this normal for a highmark kit? I need help asap

 

[rideharder]

quick question, what power jets does everyone run, i have see the mikuni ones and the dial a jet and thunder jet. anyothers? and what are best?
thanks

 

[devilrmk]

You want this type, also known as Jack Harris power jets, or clippard power jets.
http://www.ftxmotorsports.com/shop/product_info.php?cPath=37_39&products_id=35

 

[extremedesigndave]

weird question

how low does the power jet start and how high does it go? like 20-100?
just wondering if someone knows

 

[Scott1]

Mountain max turbo

Hi guys, I have been reading this post for a while now and I think I am ready to go for it, I have a 2000 mountain max 700, I have read in prior posts that the airbox from a mach z triple would be a good fit, what would you run for the turbo? What fuel pump? Has anyone seen a mm700 turbo or have any pics of one? I am definatley a rookie with boost so any help is appreciated. Thanks Scott

Looking for MACH Z triple Turbo air box

 

[Tonysnoo]

i took my sled out today and it was running great i checked the plugs and they looked good. Then it started bogging a little bit. When we stopped it shut off and was hard to get to start. Then we road a little and it was running like crap and wouldnt build boost or rev up. We stopped cleaned the plugs up and it fired and ran good for like three powder turns and shut off and wont start. It didnt have strong spark on the hill and now at home it has ok spark but wont start? The comp. is 100 and like 105. Is this normal for a highmark kit? I need help asap

I know this is going to sound silly and very basic, but have you put in new plugs? My buddies foul plugs on their turbo sleds when they run straight race. However, They do keep running...just not well.

 

[Tonysnoo]

how low does the power jet start and how high does it go? like 20-100?
just wondering if someone knows

If I understand your question, they aren't rated like a main jet. They supply supplimental fuel over and above the main jet curcuit. I've been told that it equates to the equivilant of 1 jet size of additional fuel for every 1/4 turn. So theoretically if you run 300 mains and add two turns of power valve you would be equivilant to 380 mains in fuel flow.

Hope this helps, and keep in mind there is a bit more to it that that no doubt when carbs get bigger the proportions per turn are bound to be different.

 

[canucklehead]

That is really low compression too.

 

[DragonFreak]

ya we changed the plugs and it didnt work. Then we pulled it home and it started when it was in my garage. I just put the exhaust out the side and i hope it works out tomorrow

 

[bisonboy02]

I need some help asap with my turboed non-ves 800.
This is my first 53 series turbo set-up and I just took it out today for the first test run and I need some help with the tuning. I never ran a turbo on a 2-stroke before.

I am at approx 1300 ft and the temp was approx -17c or 2f.
My current set up is 520 mains, 50 pilots, 145 starter jets, 9efy02-61 needles in the #3 position, with powerjets. Running 50/50 premium/race fuel.

My first pass it was sputtering really bad, 3-5 psi boost and no power. My fuel pressure at idle was 5psi.
I pulled the plugs and they were soaked in fuel. I didn't have the tools to rejet so I turned in the powerjets a 1/2 turn and retested. It cleaned up the performance a bit. I know I am way too rich so I turned them in all the way and backed them out a 1/4 turn. It is running better but still not good enough, my egts are around 1200f. I think I will drop the mains 4-5 sizes.

Now my boost is around 10psi. I turned in the adjusting screw on the regulator 3-4 turns and even out 3-4 turns and the boost stays right aroung 10psi.
What is the proper way to adjust the boost? Is turning the screw in more or less boost?

And do I have to adjust the fuel regulator or will it compensate the fuel with the boost line at the regulator?

Should I leave the fuel pressure at idle at 5psi, rejet and turn the powerjets out 1 1/2 turns and retry?

Should I go lower than 4-5 sizes on the mains?
Do I have to adjust the powerjets if I increase or decrease the boost?



Any info and help on this would be great

 

[devilrmk]

You are headed in the right direction with your jetting.

I am running 410 mains 30 pilots, just put in 9efy02 needles(2nd Position) Powerjets about 1.25 turns out at 4-5000ft. Runs clean but its a bit fat.


Your fuel pressure should adjust itself if you have a boost referenced regulator.

5 psi is fine.

Not sure what kind of boost adjuster you have but all that I have seen screwing out will drop boost.

I think you are on the right track dropping 4 or 5 sizes.

On your powerjets, I know Gus has stated before that he has to turn down powerjets when increasing boost.

 

[bisonboy02]

You are headed in the right direction with your jetting.

I am running 410 mains 30 pilots, just put in 9efy02 needles(2nd Position) Powerjets about 1.25 turns out at 4-5000ft. Runs clean but its a bit fat.


Your fuel pressure should adjust itself if you have a boost referenced regulator.

5 psi is fine.

Not sure what kind of boost adjuster you have but all that I have seen screwing out will drop boost.

I think you are on the right track dropping 4 or 5 sizes.

On your powerjets, I know Gus has stated before that he has to turn down powerjets when increasing boost.

I think I am going to try 460 mains and drop the pilots down to a 45.
I just found out that I have a 2 piston controller. There are 2 screws, one at the end of the housing and one at the front by the turbo housing.
Does anyone know how to adjust one of these controllers?
I never touched the screw at the turbo housing, just the end one. And know I can't remember where it was originally set....lol

 

[gus bohne]

The screws you refer to set vane start angle and vacum travel.
THEY IN NO WAY adjust boost !!!

Yes ,, set completely wrong will affect boost, but they are not for tuning the amount of boost..

Remeber when jetting !!!!!

The powerjet is in NO WAY related to mainjet !!

Your power jet comes on at roughly half throttle,, the main is not flowing at its max until 3/4 throttle.....never adjust powerjet for mainjet changes,, you will burn it in at part throttle position and think it was something else.

look at the carb as it opens and you will get the picture.

takes a little time to tune these older sytems that in reality were NEVER tuned right from the builders..

you guys are doing really good.. keep on keepin on....

Gus

 

[bisonboy02]

Gus
Do you know which screw is the vacuum and which one is the start angle?
And how do I adjust each?
Am I on the right track for jetting?
I installed 460 mains last night and readjusted the powerjets to 1 1/2 turns out. I am hoping to try it out today.

 

[gus bohne]

screw closest to turbo is the vacum side.
other is start angle.

No, I can't tell you where to set them, sorry.. old 99 series I worked with,, the 53's and 66's we stayed away from.

 

[bisonboy02]

I tried the sled again today with the 460 mains, helped a bit. I turned the powerjets in like I did with the bigger mains and it helped. I am still thinking that I am still too rich.

I know that the powerjets don't start working until 1/2 throttle, but if I am too rich on the mains and the powerjets kick in, won't it will be way too rich?

And with the powerjets turned almost all the way in, does it make sense to say that it runs better at 1/2 throttle to full throttle because it is not overfueling?

Also my turbo has a powerjet installed on the turbo also, I was told it was for lean spots at off idle. When this powerjet is turned in the bottom end response gets better. When it is turned out 1 turn the off idle position is sluggish.

I can get it to run pretty decent by turning the powerjet on the turbo all the way in and the powerjets on the carbs 1/2 turn out. But on a long pull my exhaust temps are almost 1300f. So I turned the powerjets out another 1\2 turn and it seems to be over fueling again. Is this because when the boost is up, the fuel pressure goes up and is overfueling thru the powerjets?


I hope this makes sense the way I wrote it.
Like I stated before this is all new to me, so any info on set ups would help.

 

[TWISTER]

First drop ur needles all the way down, ride if still fat start dropping the mains with the needles all the way down if i remember right u will end up down around 400 mains just go slow ideal is to get the mains low enough to have the carb powerjets 3/4 open and turbo powerjet between 1/4 to 3/4 now these are ideal but u may end up somewhere else and the sled be happy. you are really fat right now also the egt is a great tool but dont trust it check your plugs and pistons till u know where the egt reads when the motor shows its running right. My t700 egts used to read 1550 when it was happy. they will all be different trust your plugs and pistons first then ur can trust the egt.

 

[Tonysnoo]

Remeber when jetting !!!!!

The powerjet is in NO WAY related to mainjet !!

Your power jet comes on at roughly half throttle,, the main is not flowing at its max until 3/4 throttle.....never adjust powerjet for mainjet changes,, you will burn it in at part throttle position and think it was something else.

look at the carb as it opens and you will get the picture.

Gus

Hey Gus,
You have me thinkin' I have always run a short(aprox 3/8") power jet tube so that I didn't affect anything but 3/4 - WOT. That is the way I still have it set with my turbo. Should I be running a longer tube so as to start flowing earlier in the throttle opening?

 

[gus bohne]

Only if your experiencing an issue there Tony.
Your set up is really good .
sorry I haven't called, been busy with txp build and the big girl; LOL

 

[papafinger1]

The screws you refer to set vane start angle and vacum travel.
THEY IN NO WAY adjust boost !!!

Yes ,, set completely wrong will affect boost, but they are not for tuning the amount of boost..

Remeber when jetting !!!!!

The powerjet is in NO WAY related to mainjet !!

Your power jet comes on at roughly half throttle,, the main is not flowing at its max until 3/4 throttle.....never adjust powerjet for mainjet changes,, you will burn it in at part throttle position and think it was something else.

look at the carb as it opens and you will get the picture.

takes a little time to tune these older sytems that in reality were NEVER tuned right from the builders..

you guys are doing really good.. keep on keepin on....

Gus

You know I did not know that. I have always been understanding that is what the powerjets were for. Adjustment of the powerjets allow movement with variation of the main. Saying this I still believe my jetting is really close. Maybe a bit fat but at 0-3000 ft I am at 530 mains and at 8-10000 I am at 410s. About 60 jet sizes larger than stock.