I think so. I had looked at this option too - trying to save $$, lol. There's also a dyno print on this forum where someone used the stock air inlet pipes with 68s. I haven't seen data to show that there is a difference between stock and aftermarket pipes as far as flow, or where the bottleneck occurs, or at what power level it matters but if Champion says the 68 works best with the upgraded inlet pipes then I guess it makes sense to get them if you're trying to get the max out of the turbos. No shortage of snake oil out there but I don't think Champion is like that based on their heritage, board presence, etc....

 

Right with the idea of no loosing power because heat with big turbos.
But I believe 650whp with vtgs is not possible with pumpgas, all the engines I met, from Rstuning, Sportec, Switzer and Protomotive couldn't exceed 700-750. Crank hp...

 

Yes I agree with K24F, there is no way you will get more than a safe 700crank out of VTG's. the over inflated figures are usually from dyno's that have not been setup properly by the operator IMO!!!!

 

At the end of the day the dyno numbers don't really matter as much as the 100-200km/hr or 60-130mph results...

From what I've seen there are manufacturers that quote anywhere from 650-750hp with upgraded vtg packages but the times for 60-130 seem to be very close to each other...

 

I am curious to the differences between vendors VTG upgrades, vividracing doesnt provide any real details on theirs (compared to CMS in this thread at least) but they are almost half price compared to CMS...

 

Again I agree with the performance times testing it's the only way!

 

CMS VTG's are expensive because they use billet housings. It's necessary for the 68 VTG's but not for the 65 VTG's.
Other vendors use factory housings on the 65 VTG's and some also extrude honed turbine housings.
FVD VTG's are 66mm
And then there's the small and cheap 63,5 VTG's

 

Maybe their compressor blades are made from cut back coca cola cans that's why!? (Joke)

 

I had asked Proto about upgrading to 65vtgs from 63.5vtgs and was told that on pump gas the 65s they had would introduce more lag with minimal gain. If racegas, E85, or methanol was used it was worthwhile. Check with whatever manufacturer you use about their recommendations b/c Proto could easily have just sold me the 65s - like shooting fish in a barrel!

 

Have you asked about the extrude honed turbine housings?
Todd told me it has dramatic improvement in low speed boost response and much better ignition timing numbers

 

Can explain what you mean please?

 

I have the vivid turbos & like someone just said you can't get an answer out of them as to what there specs are ,I'm guessing 63.5 but does anyone know for sure ? I will be upgrading in the near future ,my tuner wants me to go gt's as I already have side air inlet pipes.

 

Any vbox numbers with the current ones?

 

If Champions 68vtg didn't exist I'd consider extruding the 63.5. Ignition timing numbers are better, which translates to more power higher up. I recall that it was good for about 0.5s drop in 100-200 time for some users.

 

A kind of polishing the inside and exit of the housing to improve the flow.