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Been doing my research on Turbo's, still have a few questions though...

1.) Why is it that you want to go with low compression (like 7:1 or 8:1) Pistons when you build a D-Series motor for boost? The weak link in the D motos is the toothpic rods, so why not go with aftermarket rods and stock pistons and be golden?

2.) On that note, how much power will the stock (D16A6) pistons hold (boosted, and nitrous; assuming it's correctly tuned)?

3.) Why not a smaller, quicker spooling turbo working at higher PSI's and towards the peak of it's power-level vs. a larger, later spooling turbo at lower PSI's, for the same power level? You get quicker spool with the smaller one, so why not?

4.) Say I bought a D16A6 and re-built it, would it be stupid to re-buld the bottom end with aftermarket rods, but stock pistons?

5.) Any recommended turbo's for a street-driven (but driven hard) D16A6 with a power goal (stock internals) around 220hp?

6.) The HF Manifold w/Adaptor Plate, does that automatically rule out AC?

7.) Why do people run the turbo with the exhuast side facing the drivers side vs. facing the passenger side? To me it looks like you could flip the turbo around so it takes the air in from the drivers side? That way you don't have to worry about making a downpipe that will fit between the turbo and the AC Compressor?

I think that's it for now, just trying to grow my knowledge. Thanks.
 

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1.) Forced induction raises the compression ratio when you are in boost, so lower compression pistons decrease the static compression ratio so that when in boost, the compression ratio won't be too high.

2.) I have seen cars with anywhere from 250 to 300 hp on stock D16 bottom ends. These are mostly the exception though and not the rule.

3.) Smaller turbos need to operate at higher boost levels in order to flow the same volume of air as larger turbos at lower boost levels. There is a trade off between bigger and smaller turbos so knowing what kind of power/where in the power band/how much power you want to make is the key to selecting your turbo.

4.) Yes, only because if you wound up needing new pistons you would have to crack the motor open again. It's never a bad idea to build too much motor rather than not enough.

5.) See number 3.

6.) I have no idea and I don't have AC anyways.

7.) Depending on your setup, you can probably face the turbo whichever direction you want, as long as everything has enough clearance.
 

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reason you dont want stock pistons is the rings are very close to the top of piston, no ring land. so they burn pretty quick. Vitara pistons are cast like stock but have teflon coating and some other goods in the metal that make them alot stronger than honda OEM. small turbos on engines that were built to breath up high in the rpm doesnt work out well. air gets hot, then no power to be made. our engines were made to make power higher in the rpm not down low. when racing you dont ever see below 5k rpms. so who cares how much power is down that low? Let that turbo spool then 4500+ rpms is balls to the wall power!!
 

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'89 CRX HF
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Been doing my research on Turbo's, still have a few questions though...

1.) Why is it that you want to go with low compression (like 7:1 or 8:1) Pistons when you build a D-Series motor for boost? The weak link in the D motos is the toothpic rods, so why not go with aftermarket rods and stock pistons and be golden? Not everyone goes with that low of compression. i run aftermarket rods and SRP stock compression pistons in my a6

2.) On that note, how much power will the stock (D16A6) pistons hold (boosted, and nitrous; assuming it's correctly tuned)? Stock a6 can reliably handle 220-250 depending on the tune

3.) Why not a smaller, quicker spooling turbo working at higher PSI's and towards the peak of it's power-level vs. a larger, later spooling turbo at lower PSI's, for the same power level? You get quicker spool with the smaller one, so why not? A smaller turbo will usually be out of its efficiency range by the time you reach the power levels that larger turbos make. unless of course is a BB turbo such as the GT28rs...which in that case the reason for not running one is because most poeple dont want to spend $1000+ on JUST the turbo

4.) Say I bought a D16A6 and re-built it, would it be stupid to re-buld the bottom end with aftermarket rods, but stock pistons? Yes, stock pistons wont handle much abuse before you lose a ring land. and on top of that, stock slugs are press fit wrist pins, and aftermarket rods only allow the use of floating wristpins

5.) Any recommended turbo's for a street-driven (but driven hard) D16A6 with a power goal (stock internals) around 220hp? Any straight t3 will get you there just fine. I would honestly run a .48/.60 from a late 80s T-bird. You can usually pick them up on ebay or the forums for under $100

6.) The HF Manifold w/Adaptor Plate, does that automatically rule out AC? Unless you want to get extremely creative(aka ghetto), yes a/c is out

7.) Why do people run the turbo with the exhuast side facing the drivers side vs. facing the passenger side? To me it looks like you could flip the turbo around so it takes the air in from the drivers side? That way you don't have to worry about making a downpipe that will fit between the turbo and the AC Compressor? Most people that run the DP on the driver side are running an a/c compatible setup. Most non a/c compatible setups run the DP on the passenger side

I think that's it for now, just trying to grow my knowledge. Thanks.
any more Qs? ;)
 

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1996 Civic EX
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if you are on some what of a budget and even if your not for our d's you just cant beat the vitara piston combo be it with a stock length rod or a custom fj ibeam rod
like sick1camcivic said the small turbos when making the same power as a larger turbo you are more likely to be pushing some hot air in the engine and you are running at a higher load on the turbo now with that said its not get the bigger turbo just because of that when you are choosing a turbo what you wanna do with the car is a even bigger factor if you are gonna auto x then a smaller quicker spooling turbo is ussually the way to go as you are generally going to use a larger rpm range where as say drag racing you would go with the larger turbo as its balls to the walls high rpm all day long
and as for why some face passenger and others drivers side is ussually you have the down pipe on the drivers side as the turbo sits in closer to the block for a/c friendly setups but you are mostly limited to a 2 1/2 down pipe where with the down pipe facing the passengers side the turbo sits out away from the block and you are then able to run 3"+ size of downpipes but you more then likely will have to give up your a/c
ic you are some what new your best bet and i know we have all heard this a thousand times is just look around and search theres everything you need to know on here
 
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