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One Tomei 2.8L crank ready for balance

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Was 1g out on balancer end and 0.6g out on flywheel end .... Usually a green light in most places :)

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Not good enough for the master.... Finely balanced till there is 0 grams variance on both ends :P ......... This can take many hours lol

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Quaife diff ...best on the market hands down.

They do read up pretty good! i have never driven a gtr with a aftermarket front diff. Cant wait! :)

Although, i did spend some time this week having a good chat to BOBBY/JEM about his build and he has definately given me some food for thought..... :blink:

1. I should avoid aftermarket front diffs as they have the potential to crack the block! (i have cracked a block in the past and it had a standard front diff) Can anybody add to this from personal experiences?

2. Cam choice... i am in fact running the same camshafts as Bobby but in opposite form i.e 260in and 270ex Tomei 10.25 lift .... i had noticed this staggered option to be quite the norm in many applications.... Obvisouly with the extensive lengths that Bobs and Skola have gone to run the opposite combo.... what would be the pros and cons of such choices?

3. Static compression and squish.... i am also aiming for a 10:1 comp ratio and had worked out the the squish would come to about 34thou.... Bobs mentioned it was imperative that it is 33thou squish otherwise the motor wont be able to run timing and detnonate........ also how much can you skim off the head and what are the downpoints of taking too much off?

To be honest, its all a bit too much to absorb :(

They do read up pretty good! i have never driven a gtr with a aftermarket front diff. Cant wait! :)

Although, i did spend some time this week having a good chat to BOBBY/JEM about his build and he has definately given me some food for thought..... :blink:

1. I should avoid aftermarket front diffs as they have the potential to crack the block! (i have cracked a block in the past and it had a standard front diff) Can anybody add to this from personal experiences?

2. Cam choice... i am in fact running the same camshafts as Bobby but in opposite form i.e 260in and 270ex Tomei 10.25 lift .... i had noticed this staggered option to be quite the norm in many applications.... Obvisouly with the extensive lengths that Bobs and Skola have gone to run the opposite combo.... what would be the pros and cons of such choices?

3. Static compression and squish.... i am also aiming for a 10:1 comp ratio and had worked out the the squish would come to about 34thou.... Bobs mentioned it was imperative that it is 33thou squish otherwise the motor wont be able to run timing and detnonate........ also how much can you skim off the head and what are the downpoints of taking too much off?

To be honest, its all a bit too much to absorb :(

Hey Steve,

It was great chatting to you giving you the info, anytime mate more then happy to help.

Just wanted to clear one factor to control squish - is by decking the block or using the correct head gasket to achieve 33 thou - decking the head will not change squish.

Hey Steve,

It was great chatting to you giving you the info, anytime mate more then happy to help.

Just wanted to clear one factor to control squish - is by decking the block or using the correct head gasket to achieve 33 thou - decking the head will not change squish.

Hey Bobs!

decking of head is more to acheive disired comp ratio..... what is your opinion on this? can you take off too much? Also can i get the details of the machinist that has the template to do the water gallery mod. Cant really find the exact details in your epic thread lol. Also what else are you doing for cooling with respect to water for your car. Are you running a water/air breather tank? Restricting water going back into the radiator at all?

:cheers:

the quench distance is measured from the face of the head where the squish pad actually is to the top of the piston at TDC, skimming the head doesnt change that distance, a thinner or thicker headgasket will change the distance between the quench pad and piston which will yield a different 'quench distance'

other things that will change the squish is machining the block face and or machining top of the piston by a few thou - i dare say that if you do decide to shave some material off the pistons it may have adverse affects on the piston if too much is taken off

Bobby can you explain how decking the head will not decrease the quench distance?

I would be interested to see how much timing and boost can be put in at 10:1 static comp.

Snozzle has answered it perfectly

Well i dont see anything wrong with running normal timing for a good engine!! you just have to get the squish right as it helps eliminate detonation and this is why you can run more timing and still have high comp.

Hey Bobs!

decking of head is more to acheive disired comp ratio..... what is your opinion on this? can you take off too much? Also can i get the details of the machinist that has the template to do the water gallery mod. Cant really find the exact details in your epic thread lol. Also what else are you doing for cooling with respect to water for your car. Are you running a water/air breather tank? Restricting water going back into the radiator at all?

:cheers:

What ever comp you are aiming for you will have to adjust your cc in the head or deck the head, this depends on how much you are decking also as there is a limit when your valve will get too close to the piston.

The machinist is Wilkins performance 9674 7037 tell him you need the head drilled to eliminate air locks. Mention my name and john skola he will remember.Yes i am running a ARC water bleeder tank you need this its very important. No not restricting water at all well im still waiting to buy a radiator as i need the motor in the car to check clearance as i will be using thermo fans.

Also the best way to measure your squish is by putting a dummy build together with a used head gasket. Place thin lead wire where the squish pads are on the piston and turn the motor once and measure the thickness. from this you can calculate if you need to deck the block or use a thinner gasket.

I hope this info helps

the quench distance is measured from the face of the head where the squish pad actually is to the top of the piston at TDC, skimming the head doesnt change that distance, a thinner or thicker headgasket will change the distance between the quench pad and piston which will yield a different 'quench distance'

other things that will change the squish is machining the block face and or machining top of the piston by a few thou - i dare say that if you do decide to shave some material off the pistons it may have adverse affects on the piston if too much is taken off

Wow that is a blonde moment if I ever had one, embarrassing... thanks mate :)

1mm gaskets and piston sitting above 0.0064" = 0.033" squish

minimum factory recommended valve clearance is 0.080" I've taken 0.090" off my 26 head to get to 10.75:1 and i still have 0.130" intake and 0.180" exhaust piston to valve clearance with a 10cc domed piston

I will check piston to valve clearance before i grind the head

What ever comp you are aiming for you will have to adjust your cc in the head or deck the head, this depends on how much you are decking also as there is a limit when your valve will get too close to the piston.

The machinist is Wilkins performance 9674 7037 tell him you need the head drilled to eliminate air locks. Mention my name and john skola he will remember.Yes i am running a ARC water bleeder tank you need this its very important. No not restricting water at all well im still waiting to buy a radiator as i need the motor in the car to check clearance as i will be using thermo fans.

Also the best way to measure your squish is by putting a dummy build together with a used head gasket. Place thin lead wire where the squish pads are on the piston and turn the motor once and measure the thickness. from this you can calculate if you need to deck the block or use a thinner gasket.

I hope this info helps

Champion !!

i will call you when i get a chance!!

:cheers:

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