why a b16 instead of a b18?
Works on MBs
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From: NOVA
Re: why a b16 instead of a b18?
i wanted to do a b20 with a swapped head and boost...and i still plan to...but doing so...i couldnt just drop in one like that....id have to build it....and i am almost impatient now and can do that later....i just want to stick something in the hatch now because im tired of being slow....and the b16 has intrigued me more than the b18
Do it!And you can use the head and the trans down the road.
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seriously...
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From: NoVA
Works on MBs
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From: NOVA
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From: Va Beach
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From: Hampton Roads
Re: why a b16 instead of a b18?
Well, each motor has its pro's and cons.
B16s have a short rod/stroke ratio
GSR's have a longer stroke ratio
Everything comes into effect, when you have goals for the car.
However, I'd choose the GSR esp since the B16 has to be in vtec to move anywhere quickly. Ha.
B16s have a short rod/stroke ratio
GSR's have a longer stroke ratio
Everything comes into effect, when you have goals for the car.
However, I'd choose the GSR esp since the B16 has to be in vtec to move anywhere quickly. Ha.
If you're going to get technical, at least get it right.
The B16 has a short stroke. 77.4mm, if I recall correctly from memory. It does that on the same bore as a B18, or 81mm.
That means the bore/stroke ratio of the B16 is 81/77.4 or1.0465, or slightly over square. This, in layman's terms, means the B16 would not mind higher RPM usage. The B18 is rather under square (think Diesel) at 89mm stroke, on the 81mm bore.
How does this apply to you? Well - The B16 won't make as much power. But it will live longer on the same strength parts, especially at higher RPM levels.
As for the Rod/Stroke - Again, we see the B16 with the advantage. How so? Well - The B16 has a 134mm rod, on a 77.4mm stroke. That's 1.73:1.
The B18 has a 137mm rod, on a 89mm stroke. That's 1.54:1.
Some of you wonder how that would be an advantage - The higher Rod/Stroke means less side loading. The disadvantage to that is dwell time at TDC and BDC. (Most race motors use 2:1 or higher rod/stroke ratios for 9K+ use)
But, basically, for forced induction, on the street - You're going to be doing pistons and rods for any major build. If you're willing to put the parts in, needed to turn 10K RPM+, The B16 should have less problems with detonation, slightly better overall head flow, and better longevity, while the B18 will spool faster and harder, make a little more power, but could have quite a few more issues over time, particularly with the high RPM use.
Also, the B18C has narrower bearings in the bottom end, which causes worse load support, and forced induction causes extreme acceleration of the piston downward. That can also become a serious problem, as evidenced by the # of people you hear about with spun rod bearings in boosted B18C motors. Simply put, wider area = less load, and the B16 Crank Journals for the rods are wider!
By the way, the reason I mention 10K+, is that if you're willing to put in good valve springs/retainers, a premium 3-layer bearing in the bottom (coating preferable,) some good I-beam rods, and a low compression (8:1) piston set, a B16 can make a nice power-band for the gearing at that RPM, and you suddenly have a VERY fast turbo car, without spending a total fortune!
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