I've purchased a turbo manifold, so i'm thinking about what turbo to pick, i can pick any turbo.

Application Info:
A15 Propane, Upgraded Ignition, Blow through propane mixer, Boost capable propane vaporizer, Intercooler.

My pick:
I looked at the compressor maps and I picked the Garrett GT1548, yeah in my application it's in the top part of the compressor map, but I figure a round port A15 won't flow as well as the Ideal 1.5L engine in the map, the turbo is specd 100-200 hp, so it seems like a good choice, i'd rather it spooled fast, I never go above 6250 rpm, so coming on to full boost earlier is good, right? Also it's got oil + water cooled bearings, yeah it's a journal bearing turbo, but to get a BB turbo with water cooled bearings it would be a much larger unit.

Opinions?

maybe look at a slightly bigger ball bearing turbo. Should spool up just as easy being ball bearing, and give a bit more headroom for increased power being bigger.

Trust T88!!!

s15 t28 would be a great turbo bit ofheadwork will get it spoolin nicely and is ball bearing might lag a bit but will come on like a steamtrain.....

how about this one:

GT2554R - 471171- 3
GT2554R

I looked at the compressor map, now that the website is working again. That seems like a better choice, true more headroom, I'd be in the lower portion of the good part of the chart.

How much air does an A15 really flow, reasonable estimates are fine...

has anyone used what i think is a t2 turbo off an early ca18et motor (single OHC)

their fairly small and have twin blades but not ball bearing,.
I want to use one on an A15 with a ported head with standard size valves.
Should spool up easily enough, well i hope.

i was orignially going to use a t2 but found that there were very few good condition ones for a decent price, if your chasing a t2 try the nissan exa forum there always selling them for about 150

I run a GT2530 on my CA18..

I'd be thinking you just need any turbo off a 1600-1800cc factory turbo car.

Plenty to choose from. Miata MX5, Mitsubishi Cordia Turbo, Subaru, Nissan..what does it matter. You'll probably be making up all the piping and manifolds yourself anyway.

Trying to find a turbo without waterlines will help.. it means less piping..

That's the thing, a turbo from a 1.6 - 1.8L vehicle wouldn't be suited to my vehicle very well, Since I'm doing this from scratch, I can get the best possible match.

Compressor maps are interesting to look at, you can really tweak a turbo if you have one that's already a good fit.

water cooling lines aren't a problem, it's worth the effort to not have oil frying in the bearings as much.

Another reason the GT1548 was a bad choice, the outlet was 50mm and all my other stuff is about 60-62mm. The other one has a 60mm outlet.

Further reading on compressor maps...
Did some calculations initially just wanting to find the Lb/min air usage so I could nail down exactly which turbo, and something interesting appeared.

LPG needs more air than petrol, so that pushes it's Lb/min into higher area, now the SR20DET turbo looks like a good match, I wouldn't have expected that.

I'll show my work:

To plot the compres

sor operating point, first calculate airflow:

Where: