| testingcheck |
| I have a friend that is selling a '94 Honda Accord 2.2L Vtec engine (no tranny). I was just wondering what are the specs of this engine and is it worth putting it into a '91 integra? Or should I wait until I have enough for a different one? |
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| silverTEG |
wait.
seriously. |
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| DomesticDrifter |
wait.
b18c1 or b18c5 will be better suited and easier to sawp into the car. |
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| scooby_dooby |
| turbo the LS, |
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| midnite |
| i'd go with a b series. |
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| Xpnsve |
Slap a turbo on one
There are many decisions that need to be made when adding a turbocharger to an engine that was not designed for one. These options include whether or not to go with a stock motor or a motor rebuilt with aftermarket parts. Whether to run the non-VTEC LS, VTEC, or LS-VTEC motor is another, often controversial, decision that needs to be made. Realize that an entire guide can be written on this topic, as such, no attempt was made to make this section exhaustive. This section will present the advantages and disadvantages of the most popular motors and whether or not to rebuild them with aftermarket parts or leave them stock.
B18A/B
The B18A/B is an excellent engine to turbocharge especially since it is the engine most 90-93 Integras come with. The long stroke enables the B18A/B, AKA LS motor (although they were available in the RS, LS, and GS trim models), to put down impressive torque numbers, specifically top end torque. The stock compression ratio, at 9.2:1, is also ideal for boost. All things being equal, at a given horsepower, the LS motor will put down more torque than a VTEC counterpart, however the LS motor will require more boost to get to that given horsepower. The horsepower to torque differential, on average, is 10% in the LS motor (stock stroke and displacement) and 20% in the VTEC equipped counterpart. This motor is particularly reliable as well. Stock LS motors have been boosted to 300hp with proper fuel / engine management. Boosting at these levels requires precise tuning as the slightest bit of detonation can lead to terminal engine failure. Built LS motors have seen 500+ horsepower.
B17
The B17, which came in the 92-93 GSR, is a VTEC motor which has some characteristics that need to be addressed when turbocharging. The 9.7:1 compression ratio must be kept in mind when tuning the car. With the higher compression ratio less boost will be required to reach a horsepower goal than it would with a lower compression engine. Also, due to the VTEC system, cam timing on the B17 raises some issues that need attention. The valve overlap, intake and exhaust valves open at the same time, can lead to exhaust gas reversion issues. Reversion occurs during valve overlap and exhaust gasses are drawn back into the cylinder. Obviously this is not a good thing when you are forcing an already hot, pressurized intake charge into the cylinder. It can lead to detonation and generally poor performance. Fortunately with the use of adjustable cam gears the overlap can be tuned out. B17, and all other VTEC motors, will put out more horsepower with less boost than a non-VTEC motor, about 14% on average. Stock B17s have seen 300hp while built motors have seen 500+ horsepower.
B16
The B16 is a very common swap into 90-93 Integras. As with the B17, the motor has some characteristics that need to be addressed when turbocharging. The 10.1:1 or 10.4:1 compression ratio must be kept in mind when tuning the car. With the higher compression ratio, less boost will be required to reach a horsepower goal than it would with a lower compression engine. Also, due to the VTEC system, cam timing on the B16 raises some issues that need attention. The valve overlap, intake and exhaust valves open at the same time, can lead to exhaust gasses reversion issues. Reversion occurs during valve overlap and exhaust gasses are drawn back into the cylinder. Obviously this is not a good thing when you are forcing an already hot, pressurized intake charge into the cylinder. It can lead to detonation and generally poor performance. Fortunately with the use of adjustable cam gears the overlap can be tuned out. B16, and all other VTEC motors, will put out more horsepower with less boost than a non-VTEC motor, about 14% on average. Stock B16s have seen 300hp while built motors have seen 500+ horsepower.
B18C
The B18C is not a very common swap into the 90-93 Integra. However the larger displacement over the B16 does have advantages. As with the other VTEC motors, the B18C has some characteristics that need to be addressed when turbocharging. The 10.1:1 compression ratio must be kept in mind when tuning the car. With the higher compression ratio, less boost will be required to reach a horsepower goal than it would with a lower compression engine. Also, due to the VTEC system, cam timing on the B18C raises some issues that need attention. The valve overlap, intake and exhaust valves open at the same time, can lead to exhaust gasses reversion issues. Reversion occurs during valve overlap and exhaust gasses are drawn back into the cylinder. Obviously this is not a good thing when you are forcing an already hot, pressurized intake charge into the cylinder. It can lead to detonation and generally poor performance. Fortunately with the use of adjustable cam gears the overlap can be tuned out. B18C, and all other VTEC motors, will put out more horsepower with less boost than a non-VTEC motor, about 14% on average. Stock B18Cs have seen 300hp while built motors have seen 500+ horsepower.
B20
The B20 motor is a direct replacement for the B18A/B. The only advantage of the B20 over the LS motor is the extra two tenths of a liter displacement. This extra displacement comes at a price however. In order to achieve 2.0 liters of displacement the cylinder sleeves are manufactured at 84mm instead of the 81mm on other B series sleeves. The design of these sleeves varies slightly from other Honda sleeves which accounts for their cracking more easily. A simpler way to achieve the 2.0 liters of displacement is to resleeve a LS motor and bore it to 84mm. Also consider that the B20 is much harder to find, which can make them considerably more expensive than a LS motor. B20 compression ratios are 8.8:1, 9.2:1, or 9.6:1 depending on year.
LS/VTEC
A turbocharged LS/VTEC is a very potent motor. However it is also the hardest to build so that it runs reliably. The LS/VTEC gives the best that the LS and VTEC motors have to offer, the high horsepower from the VTEC and the high torque of the LS. By using the LS block and a B16 head (with a stock bottom end) a compression ratio close to 9.0:1 is attained. If rebuilding the motor, the block can be resleeved with aftermarket sleeves and bored to 84mm resulting in 2.0 liters of displacement. A reliable LS/VTEC motor is very difficult to build, as such it should only be attempted by an engine builder experienced with building LS/VTEC motors. Since building a good LS/VTEC motor is such an art, engine builders charge a premium for their services. Also keep in mind that the bottom end of a LS motor was not designed to rev up to the level where the VTEC motors are meant to shine.
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| tokes |
quote:
Originally posted by Xpnsve
Also, due to the VTEC system, cam timing on the B18C raises some issues that need attention. The valve overlap, intake and exhaust valves open at the same time, can lead to exhaust gasses reversion issues. Reversion occurs during valve overlap and exhaust gasses are drawn back into the cylinder. Obviously this is not a good thing when you are forcing an already hot, pressurized intake charge into the cylinder. It can lead to detonation and generally poor performance. Fortunately with the use of adjustable cam gears the overlap can be tuned out.
If you paid attention to anything, you would see a lot of turbo hondas being tuned that are making MORE POWER all over the RPM range by advancing the intake cams more than the exhaust cams, which dials in more overlap! Overlap at high RPM's is what creates high volumetric efficiency, and which is what leads to high horsepower. Go look at a bunch of the cars tuned on www.evans-tuning.com/forums recently, 40 WHP on a 350 WHP setup by dialing in more overlap with the cam gears.
quote:
Originally posted by Xpnsve
LS/VTEC
A turbocharged LS/VTEC is a very potent motor. However it is also the hardest to build so that it runs reliably. The LS/VTEC gives the best that the LS and VTEC motors have to offer, the high horsepower from the VTEC and the high torque of the LS. By using the LS block and a B16 head (with a stock bottom end) a compression ratio close to 9.0:1 is attained. If rebuilding the motor, the block can be resleeved with aftermarket sleeves and bored to 84mm resulting in 2.0 liters of displacement. A reliable LS/VTEC motor is very difficult to build, as such it should only be attempted by an engine builder experienced with building LS/VTEC motors. Since building a good LS/VTEC motor is such an art, engine builders charge a premium for their services. Also keep in mind that the bottom end of a LS motor was not designed to rev up to the level where the VTEC motors are meant to shine.
For starters, the LS bottom end is not what makes the LS motor produce a lot of torque. The LS head, small cams, and long runner intake mean you make more torque at a given horsepower level than GSR motors. If a GSR needs 9 psi to make 300 WHP an LS will need around 14. 14 psi hitting at 4000 RPM's creates much more cylinder pressure and TORQUE than 9 psi does at 4000 RPM's. An LS at 9 psi will make a bit more torque than a GSR at 9 psi, but since the GSR carries that torque to higher RPM's it makes more peak power.
Compression with a B16 head on a stock LS block is about 9.55:1, and about 9.73:1 with a GSR head. Not 9:1.
Building an LS/VTEC is not "an art" and if any engine builder charges you more money to assemble an LS/VTEC than he does for a GSR motor I hope he includes the KY, because you're getting royally fucked on that deal. The 1.54:1 Rod-to-Stroke ratio produces piston speeds and side loading on the walls and skirts that are about 1% higher than a GSR motor, if you're turning 9500 RPM's
Do you have any idea how big the difference in stroke is between the GSR and the LS? 1.8mm, or about .070". If you take a motor with LS crank/rods, swap that out for GSR crank and rods at the same compression ratio you would not notice a difference driving the car, and the difference on a dyno might be 3 or 4 RWTQ at peak. |
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| silverTEG |
| wow this thread just won the award for "the most technical thread ever on 780 tuners" . congrats :bthumbup: |
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| DomesticDrifter |
| wow:tear: |
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| scooby_dooby |
quote:
Originally posted by tokes
Building an LS/VTEC is not "an art" and if any engine builder charges you more money to assemble an LS/VTEC than he does for a GSR motor I hope he includes the KY, because you're getting royally fucked on that deal. The 1.54:1 Rod-to-Stroke ratio produces piston speeds and side loading on the walls and skirts that are about 1% higher than a GSR motor, if you're turning 9500 RPM's
Do you have any idea how big the difference in stroke is between the GSR and the LS? 1.8mm, or about .070". If you take a motor with LS crank/rods, swap that out for GSR crank and rods at the same compression ratio you would not notice a difference driving the car, and the difference on a dyno might be 3 or 4 RWTQ at peak. [/B]
xpnsve was just posting an article, if you want to argue with someone it would be the orginal author.
The main reason ls/vtec's are so unreliable on a stock bottom end has almost nothing to do with the slightly longer stroker. The LS bottom end has no block girdle, is not balanced as well, no oil squirters and most importantly skinny-ass rods and weak rod bolts. Even the engine bearings, oil and water pumps are inadequate on the LS bottom end.
The main reason they fail is from revving too high(spun bearing, stretched rod bolt) or lack of proper oil circulation(inexperienced builder.) I don't know if it's an art, but you definately want someone with experience doing ls/vtecs specifically, at least I would if it were my engine.
Everything else you said was right on. |
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