Compounds

I realize I am opening the old can-o-worms, but anyone had a good experience with a particular size turbo over and H1C framed high pressure unit (in my case, hybrid 62/86mm H1C/14cm3)?
It is possible that, at my altitude and very thin air that I should use my existing turbo as the low-pressure unit because my turbo is a little lazy on the bottom end, and very fast on the top end. I'm shifting into 5th gear at 90 mph.

mhuppertz said:

I realize I am opening the old can-o-worms, but anyone had a good experience with a particular size turbo over and H1C framed high pressure unit (in my case, hybrid 62/86mm H1C/14cm3)?
It is possible that, at my altitude and very thin air that I should use my existing turbo as the low-pressure unit because my turbo is a little lazy on the bottom end, and very fast on the top end. I'm shifting into 5th gear at 90 mph.

Click to expand...

If it's lazy now, it won't get any faster as a secondary. The best spooling setup I've ever seen or built on a VE truck was a S300g 58/65/14 over a S478 with a 78mm Extended tip wheel, small turbine which I think is 87mm and a 1.10 housing.

With a 3200rpm limit, you don't need a lot of top end breathing with the bigger housings and wheels in my opinion.

But, as to your question, and S400 framed charger should spool and match good enough for you, or if you want really good spool, go with a bigger S300 charger, like a 66 or 69mm like the old school BD Tow Twins were. They were 58mm over a 66mm and up to 425-450hp they were unbeatable for spool and towing performance. Now, for all out performance, they were just too small.

Chris