I have a JDM B16A engine and i swapped out the PR3 pistons with A0 P73 pistons and the rods are the original PR3 rods. What is the maximum about of boost will i be able to push (if any)? I am looking at a 10psi turbo right now but i have no idea how it will go with my pistons. Please help!

 

Your going to get a lot of opinions on here (if people decide to respond) but to answer your question it is possible. Is it a realistic decision, probably not.

I'd search through the archives and see if you can find some additional information on what is exactly feasible for your build

Good Luck!

 

11:1 seems to be as high as people go on pump gas with boost

why? no idea, maybe a tuner will pop in and go over the details.

 

i'm running 11.5.1 on e85 and have 0 problems yet. car has been running for 7 months.

 

it will work fine but wont be reliable on pump gas best bet get tuned on e85 with big injector 1000cc+

 

The 2ZZ-GE is 1.8L and is 11.5:1. We supercharge them to 300ish to the wheels on pump gas. I use 93 octane.
This requires about 10-12 PSI. and I think some have gone up to about 330WHP on stock motor. The B18C5, which is of course 1.8L, is 10.6:1 and I know people take those up to 300+HP on stock motors regularly.

So yes, high compression and forced induction work really well together. But your ceiling is greatly reduced compared to a low compression motor. However the high compression motor will still respond well while in vacuum and will be more effecient. I wouldn't look at from a "boost" perspective but more a power perspective. With 1.6L, rule of thumb says your gonna be lower then what the 1.8's can do.

According to this webpage it says P73 in a B16 should be about 10.8:1. Does that sound right? Just a wild guess pulled from my ***, but I think 300WHP would be a good goal.

 

The longevity of the set up will be based on the quality of the tune.

You can use both boost and high compression pistons, but will require a really good tune, so pick your tuner carefully or risk

 

My set-up produced 387 whp and 225 ft-lbs @ 9000 rpm on 93 octane @11 lbs of boost.

The set-up:

Drivetrain-
Block- B18C1, OEM gsr crank + rods, 81.5 mm RS machine pistons (PTW 0.002"), OEM main bearings (bearing clearance 0.0018"), and ACL rod bearings (bearing clearance 0.0018")
Head- B16A2, stock port, stock valves
VT- Supertech springs H1002D, and 2002 rsx type-s retainers
Cams- Pro2 intake and Blox C exhaust
TB- Professional Products 68 mm
Ignition- Stock Dizzy, wires, and NGK 8's
Fuel Delivery- Walbro 255 and ID1000
EMS- OBD-1 converison, chipped P28, neptune'd
Trans- S4C, cable to hydro bracket, and CC stg 2 clutch

Turbocharger-
Turbo- Holset H1C model 3531456, 18 cm^2 exhaust housing with 3" v-band (DIY)
Manifold- Mini-ramhorn 1.5" sch 10 fitting (DIY), (Importdps)
Wastegate- Tial 38 mm
Oiling- GE Vtec sandwich plate, -4AN stainless braid (feedside), 12 mm x 1.5 to -4AN flare, -10AN stainless braid (return side)
Hotside charge piping- 2.5" Aluminum piping (Dynamic Performance)
Coldside charge piping - 3.0" ALuminum piping (Dynamic Performance)
Intercooler- Precision 600 Hp (Importdps)
BOV- Tial 50 mm
Map sensor - GM 3 bar
Downpipe- 3.0" stainless steel (IMW)
Exhaust- 3.0" stainless steel (Synapse Motorsports)

Parts (Importdps, Xenocron, and Verocious)
Tuning (IMW)

And the plots







Please note: high compression and big cams on 93. Follow this recipe and you will not have a problem.

 

one of boys car is lsv with a gsr head on the p73 pistons on just arp rod bolts and arp headstuds making 335 on 11 psi on 93 for the last 2 years

 

you lowered the compression not raised it. You should be aroud 10:1 with an uncut block/head and those pistons.

 

stock gsr on e85 here right at 600whp

 

yea my compression right now is at 10.8:1 not 11.1:1...i have the USDM P73 pistons not the JDM ones...i also forgot to mention i have the ARP Head bolts on my car now if that matters? I am not really looking to get crazy HP out of this, i just got a great deal on a turbo and i dont want go ahead and put it on my engine right away not knowing how it will react with my pistons, i dont want any bent rods or mess up my engine in any way because i just rebuilt it about 2000 miles ago

 

this is the only person in this thread that even remotely read the ops setup.

your compression is not 10.8 or 11:1, its right around 10.0:1 because the piston you put in has a SMALLER dome than the original piston. so the OPs motor is a b16 with less compression than stock. its good for 300whp give or take a little on pump safely.

 

are you at altitude? that will make a difference. It depends on alot of other things. Size of turbo, other mods to the engine, fuel used. I made 488whp on a stock internal gsr and it lived for 8months on e85. If you have a good tuner he can make almost anything work for a little while

 

10.04:1 according to Zeal Auto Works. That's not bad. Stock internals are said to be good for about 250-300 reliably. Yes people like dantamparacer push them farther, but their life will be short lived as he said.

Everyone says to lower compression, although when you lower compression you have to run more boost to make the same amount of power. If you just have more compression, it will make more power sooner. The importance of a very good tune just becomes very apparent.

 

You are missing the other half.. Big cams + high compression is good, but if you had a log manifold and a 2.5" exhaust it will blow into pieces very shortly.

It's big cams, high compression tubular manifold, big turbine housing, good flowing downpipe and exhaust (catless). Once you have cams, it needs to scavenge, and you are making power from good efficiency and not brute cylinder filling. Anything that works against scavenging, you are looking for trouble!

So imagine your current setup, but with a GT2871R, it will not run well at all regardless how big the cams are

 

Interesting info most def!!! can anyone give me any insight on a safe power limit, i'm switching back to 93 octane from E85 (just not enough in the area) stock block b16 with with nippon racing ctr pistons (stock bore) ITR cams, and a precision 6031 .63 hotside, Go-autoworks ramhorn, numbers in sig!

 

Turns out p73 a0 pistons have a lower compression ratio than the PR3, is this correct? P73 A0 makes 10.1:1 and PR3 do about 10:4:1 is this right?

 

Thanks man, your the only one that actually knows what they are talking about!!

 

should be even less if memory serves. the difference between jdm and usdm itr is .4 point. i thought the pr3 aka b16 pistons were slightly taller than jdm itr