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gatto-is-alive

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b16a1 block stock crank + stock rods machined out to fit itr stock pistons + itr stock pistons + stock head gasket + stock gsr head + itr cams + b16a im

what is the result ??

i m gonna build this mess in a few weeks but i m still not sure about some of the components to be th right ones .
i have allready tried out the itr pistons in a stock b 16 and had unbelievable results but now collecteb some other parts an want to try a new kind of beast:D

if anybody has tried this pls post your comments about it 10x


FROM MALTA
 
I would go with a Skunk2 IM instead of the B16 IM, along w/ a ITR TB, will be better for the ITR cams. and you will have to custom fit the B16 IM to fit on a GSR head
 
head was manually ported and port polished to mirror finish , got dual valve springs on the exhaust valves too, im is in progress to make it fit and then it will be ported too,then when finished i have to get it tuned for some more power
 
head was manually ported and port polished to mirror finish , got dual valve springs on the exhaust valves too, im is in progress to make it fit and then it will be ported too,then when finished i have to get it tuned for some more power


Thats a shitty P&P. A mirror finish is about the worst thing you can do to a head.
 
b16a1 block stock crank + stock rods machined out to fit itr stock pistons + itr stock pistons + stock head gasket + stock gsr head + itr cams + b16a im

what is the result ??

About 9.7:1 compression if you're using USDM ITR pistons, and 10.1:1 if using JDM ITR pistons- so basically a lower compression B16 with larger cams than stock. I'd put you right about the power levels of a stock B16, maybe slightly higher.

If I did the math right. Rusty. But pretty sure.
 
11.0:1

The CTR pistons have the higher compression height because they came in a B16 stroke block. Instead of spending money on hard to find OEM pistons though, I'd just go for a nice set of aftermarket forged pistons and rods. Pick your compression ratio.
 
ctr cams are the same as itr if they're newer than 98? i think thats the year. terrible compression for all motor with the itr pistons (9.9usdm) and less displacement then a 1.6 d-series..

+1 get some je 11.1's.

custom fab for b16 mani on the gsr head, get a skunk2 imo.
 
Thats a shitty P&P. A mirror finish is about the worst thing you can do to a head.

half right. you usually want the cc and the exhaust ports to be mirror so that carbon can't build up and then the intake to be a little rough so that the fuel can properly atomize.

Edit: I wouldn't say it's the worst thing either, i think that having a mirror intake surface will only reduce performance by something like 1%. I would be much more concerned with who ported the head, because if someone doesn't know what they are doing they can actually reduce the flow by making it larger.
 
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the head was ported with a dremel tool but only few mm was taken off something like 1-2 in some particular areas and i think that having smooteed out surfaces at the intake ports will reduce friction to air and fuel so it will gain better flow.

if i'm wrong please correct me i did this job but it is the first time for me porting a head and i'm still in time to correct my work so 10x in advance.

the pistons are from a jdm itr so what will be the best ,keeping the stock p30 pistons or the jdm p73 for this setup?
 
the head was ported with a dremel tool but only few mm was taken off something like 1-2 in some particular areas and i think that having smooteed out surfaces at the intake ports will reduce friction to air and fuel so it will gain better flow.

if i'm wrong please correct me i did this job but it is the first time for me porting a head and i'm still in time to correct my work so 10x in advance.

the pistons are from a jdm itr so what will be the best ,keeping the stock p30 pistons or the jdm p73 for this setup?

for fluid flow, the molecules that are directly contacting the surface are stationary. as move towards the center of flow, the velocity of the fluid increases. The only way that the surface roughness would have an effect on fluid flow is if the surface is so rough the bumps acutally get into the flow.
 
the pistons are from a jdm itr so what will be the best ,keeping the stock p30 pistons or the jdm p73 for this setup?

Honestly- the stock P30 pistons. They have a larger volume dome, and they'll sit higher in the bore.
 
as i said earlier in this thread i had great results by istalling a a set of itr (jdm) pistons in a stock b16a1 that setup decreased my 1/4mile time from 14.2 to 13.6 with no other changes in the car.
now i dont know why you are saying that itr pistons have smaller dome .
when i did the swap i noticed that the itrs where higher by 1.5 -2 mm than the stock p30s

notice i had to machine out the rods to fit these bcos the itr rods are a bit narrower than the b16a.

could it effect the performance so much by having the rods a bit lightier???????????
dont think so!
 
P30s do have a larger dome, but sit slightly lower in the block than ITR/P73 pistons. PCTs, on the other hand, have the largest dome and sit higher than even the ITR pistons.

As for the performance gain(if there was no tune), it was probably due to driving and possibly weather. May even be due to fresh rings that seal better(higher chamber pressures). Compression would only go up about .1:1 and combustion chamber shape would be very similar. I can see how a reduction in dome but higher compression height would help, but I don't see it dropping your times by that much. Did the trap speed change?
 
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