vmax turbo help

Low compression would explain why you wasn't building boost. Being that your running a turbo I would put 2 new pistons to be safe.
What's in it now for weight?
 

Sorry i should have said it better, it had 120 on both sides, then i popped the pto side. The weights are stock in it now. Secondary is stock as well.
 
Maybe just a couple grams in the tip or maybe a set of 8ca with 13.9 in both holes.
I'm not really sure just throwing out what I think would help.
 
I read somewhere that srx clutches work pretty good with the increase in power.
Any thoughts?
 
Got it apart today, here's a pic of the piston, unfortunately the jug is scored.
IMG_20160131_140001.jpg
IMG_20160131_135138.jpg
IMG_20160131_135119.jpg
It's the exhaust side that is messed up.
Any thoughts if was lean or something else?
 
You need forged pistons in BOTH cyl. What exact pressure (both boost and fuel) are you running at WOT? Did you check your gauges to mare sure they are true? You need a power jet system. Don't play the needle, your not making boost in that area. Dont wrap your pipe.
 
Toydoc Is there a specific forged piston make that is better than others?
At wot I was only getting around 2-3 ps boost., must have had a bunch of air leaks. Fuel is set at 5 psi and is a Mallory 1 to 1 rising. How do I test my gauges? I've never done it.
Pipe wrap will go, is that because it holds the heat and affects the tuning of the pipe?
Where do you recommend putting the power jet? A single In the charge tube or a pair in the carbs?
Any and all help is greatly appreciated.
 
Can anyone recommend what power jet brand and where to get it.
Also should I run one at each carb or a single one in the charge tube?
 
Can anyone recommend what power jet brand and where to get it.
Also should I run one at each carb or a single one in the charge tube?
 
lunnex said:
Toydoc Is there a specific forged piston make that is better than others?
At wot I was only getting around 2-3 ps boost., must have had a bunch of air leaks.
You can have that many exhaust leaks. It would be super loud. Likely your turbo needs to be looked over / rebuilt. You may what to check before you put too much $$ it to your setup.

Fuel is set at 5 psi and is a Mallory 1 to 1 rising. How do I test my gauges? I've never done it.
Not sure what you have. Why not use what what it came with? Fix the leak.

Pipe wrap will go, is that because it holds the heat and affects the tuning of the pipe?
You push heat into the piston. See piston pics.

Where do you recommend putting the power jet? A single In the charge tube or a pair in the carbs?
Use factory Mikuni power jets. One in EACH carb. Install instructions will be in the package. Start at 100 PJ, stock MJ and clip

Any and all help is greatly appreciated.
Click to expand...

See above in green
 
It's been a long while, but I'm still poking away at the old girl. Recap: aerocharger has self destructed resulting in a rebuild. Purchased a turbo kit from a rx1 and retro fitted it to the machine. This ment having to add a oil pump and tank. Also added a/ f gauge, oil gauge and new exhaust. Power jets were also added. Then when first trying the new setup, I found out the seals were shot in the turbo and a rebuild kit is not available. So off I went in search for another turbo. This time I sources a Borg Warner from a 2015 ford escape 1.5L. This time I tested it first! Refabricated the exhaust again and now it's up and running. On a side note, this turbo has a type of recirculating electronic BOV, so I wired to the tors switch at the thumb throttle. This will open the BOV everyone the throttle is released. Seems to work well.
So now my I am in need of a little tuning help. Seems to be very boggy when hammered from an idle. Will even backfire threw carbs. It I brake torque it to around 2_3 psi it will take off no problems. Once the revs are up seems to be quite responsive. I have not changed the jetting from my earlier posts, other than the power jets.( They are 100s) mounted on the intake side of the carbs.
I do know there are a couple of small air leaks but it's been tough trying to do a leak test as it is leaking at the y pipe / pipe connection, and it's a total pita to remove the pipe to seal it there. Any advice is greatly appreciated.
 
This is an interesting project, and I applaud your efforts, but realisticly, don't think many who are presently active on this forum can answers your tuning questions...
 
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Thanks, just thought I would throw it out there. I know it's been a long time and many members are not around.
 
If anything I enjoyed reading through this, cool to see you're still working at it!
 
I saw an episode of Snowmobile television in which they installed a turbo kit on a Polaris triple and it gave zero increase in performance. It probably not worth the headache.
 
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