Supra TT pistons + B16a Rods = D16A6
01-06-2003, 08:13 PM
#22
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Join Date: Dec 2002
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Re:Supra TT pistons + B16a Rods = D16A6
I don't know if anyone has mentioned this, but the 1g-gte was used in mid to late 80's jdm supras and soarers (I believe they were 2.0 liters). They aren't from the US market twin turbo which is the 2jz-gte, so the 1g-gte pistons may be more difficult to find than anticipated. Hope this helps and good luck! 
01-06-2003, 08:47 PM
#23
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Re:Supra TT pistons + B16a Rods = D16A6
Before anyone does this, be aware the compression will be horrendously low on a d16a6 (crx/civic).
I calculated it as below 8:1!!!! This will make the engine limp until at least some boost kicks in.
The pistons will not go as high in the cylinder as stock so the compression will be real low. The stroke length is still the same (bottom of the stroke is lower than stock).
I calculated it as below 8:1!!!! This will make the engine limp until at least some boost kicks in.
The pistons will not go as high in the cylinder as stock so the compression will be real low. The stroke length is still the same (bottom of the stroke is lower than stock).
01-06-2003, 10:45 PM
#25
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Re:Supra TT pistons + B16a Rods = D16A6
the compression height of the piston is important too, find out how far it is from the center of the wristpin bore to the top of the piston. you could have the machine shop deck the block some to reduce compression, but this can affect valve timing, and piston to valve clkearance can be an issue as well.
01-06-2003, 10:59 PM
#26
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Re:Supra TT pistons + B16a Rods = D16A6
When I first started looking at this setup, "TurboPanda" (I think he changed his name since) said the pistons stop 1mm lower than stock from the top of the cylinder at TDC.
This takes wrist pins and such out of the equation. Basically this adds 1mm worth of cylinder volume extra to the "compressed" side of the ratio.
I wish I kept the numbers, but I was shocked. If people have any ratios on adding 1mm thicker than stock head gasket, the result should be the same I think.
Considering a d16a6 starts out with 9.1:1, It's probably not a great idea to lower compression any more.
I will try to recalc the numbers.
John
This takes wrist pins and such out of the equation. Basically this adds 1mm worth of cylinder volume extra to the "compressed" side of the ratio.
I wish I kept the numbers, but I was shocked. If people have any ratios on adding 1mm thicker than stock head gasket, the result should be the same I think.
Considering a d16a6 starts out with 9.1:1, It's probably not a great idea to lower compression any more.
I will try to recalc the numbers.
John
01-06-2003, 11:19 PM
#28
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Re:Supra TT pistons + B16a Rods = D16A6
jthelman
you said that it adds 1mm to the compressed volume, but it also adds it to the uncompressed volume of the cylinder.you probably know this, but i just want to make sure you didnt miscalculate
you said that it adds 1mm to the compressed volume, but it also adds it to the uncompressed volume of the cylinder.you probably know this, but i just want to make sure you didnt miscalculate
01-06-2003, 11:46 PM
#30
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Re:Supra TT pistons + B16a Rods = D16A6
okay, i did some quick calculation,
assuming that the bore is 87 mm(stock)
the displacement of 1 cyl is 399.25cc(1597/4)
and a 49cc uncompressed volume would yeild 9.14:1 CR
adding 5.9cc(the 1 mm difference) to both compressed and uncompressed volumes equals
8.27:1 CR
low, but a good ratio for cheap fuel system upgrades and really high boost. i think its a good setup.
if the block was decked .25mmand the head was decked .25 mm the Compression would be 8.7:1, and those deck heights would deffinitely be acceptable if the engine was clayed to check piston to valve clearance,
valve timing would be altered a couple of degrees, but nothing an adjustable cam sprocket cant accomodate for.
that sounds like some old school ingenuity to me.
let me know if anyone can find more accurate numbers or if i screwed up, which isn't too unlikely
assuming that the bore is 87 mm(stock)
the displacement of 1 cyl is 399.25cc(1597/4)
and a 49cc uncompressed volume would yeild 9.14:1 CR
adding 5.9cc(the 1 mm difference) to both compressed and uncompressed volumes equals
8.27:1 CR
low, but a good ratio for cheap fuel system upgrades and really high boost. i think its a good setup.
if the block was decked .25mmand the head was decked .25 mm the Compression would be 8.7:1, and those deck heights would deffinitely be acceptable if the engine was clayed to check piston to valve clearance,
valve timing would be altered a couple of degrees, but nothing an adjustable cam sprocket cant accomodate for.
that sounds like some old school ingenuity to me.
let me know if anyone can find more accurate numbers or if i screwed up, which isn't too unlikely
