R34 Gtr Build

[tangomatt]

Sorry to digress from the details of the engine build itself. But I must say the interior retrim is already another highlight of this build. The leather and alcantara combo and stitching details look classy.

But may I ask who did the interior re-trim for you? Judging from the photos posted on the JEM website, the quality looks outstanding, matching, if not surpassing the Robson Japan's standards. The leather looks perfectly smooth and moulded to the front seat base contours and side bolsters. This is said to be almost impossible to achieve by a few (well known) automotive trimmers in Melbourne.

Do you know the process involved? Did the trimmer have to peel the original OEM fabric off the seats or was the leather simply glued on top?

Cheers

Matt

[BOBBYr34]

Sorry to digress from the details of the engine build itself. But I must say the interior retrim is already another highlight of this build. The leather and alcantara combo and stitching details look classy.

But may I ask who did the interior re-trim for you? Judging from the photos posted on the JEM website, the quality looks outstanding, matching, if not surpassing the Robson Japan's standards. The leather looks perfectly smooth and moulded to the front seat base contours and side bolsters. This is said to be almost impossible to achieve by a few (well known) automotive trimmers in Melbourne.

Do you know the process involved? Did the trimmer have to peel the original OEM fabric off the seats or was the leather simply glued on top?

Cheers

Matt

I had my car at Bodyform Peter the master at the finishing touch he said to me, let me do the interior, a person like me that is very picky and want things done perfectly he got it done for me and trust me it was not expensive compared to what i have spent on my other cars.

He removed the old oem fabric and if you, sit in the seats they feel better then the Z-tune ,i know i should not say that but its true LOL. If you want it done i could organise it for you.

Also the pic's do not justify the look, they look much better in real life. I found another pic

Bobby

[Beer Baron]

The par was the best option as ppg have had problems wth the 6 speed, hollinger i could of used with sequential changer would had to change front and rear diff and change the transfer case and the tail shaft for the front and again all three boxes can break.

Par i have had in the past and did have some issues with it, they have now fixed the problem and this box i bought is full dog engagement ( gonna have fun driving it lol ) I will be adding the ignition cut for quick gear changing.

hey bob. awesome car mate. love it.

just 1 question though. I'm not sure what you mean about the hollinger box? you do not need to change transfer case, or front diff or rear diff to run a hollinger. yes you need a new tailshaft but the hollinger is far superior to PPG, PAR or the modena. it uses a completely different casing design, is smaller, lighter, stronger, smoother and offers much faster shifts being a sequential box (it's not an h pattern box with a sequential 'changer' so i'm not sure who gave you that advice). it will probably be easier to drive around town than a full dog engagement PAR box to be honest. the problem with gearsets like the PPG and PAR is they use the factory casing and many factory parts in which there are weaknesses. the hollinger uses none. they make a bellhousing adapter and it mates up to the factory transfer case no problem.

my advise would be sell the PAR and get the hollinger. you will not regret it. for a car that has big power and is a mix of street, drag and circuit the hollinger is a much better choice. it's a big outlay up front but saves money and headaches in the long run.

[SimonR32]

I would agree with the Hollinger being a heap better in every way...

There is only one real draw back that while driving around town you can never skip gears on downchanges

[NickR33]

John also stated a very important note about the RB26 - Very small stroke small cc very heavy car he did say this motor needed to be at least a 4L for the weight R34 gtr is about 1680kg

quoted for truth!

you mention not going for Vcam because 'the motor will be built with the correct cam timing and static compression this will work the same way' can you explain this a bit for me in lay-mans terms?

[BOBBYr34]

hey bob. awesome car mate. love it.

just 1 question though. I'm not sure what you mean about the hollinger box? you do not need to change transfer case, or front diff or rear diff to run a hollinger. yes you need a new tailshaft but the hollinger is far superior to PPG, PAR or the modena. it uses a completely different casing design, is smaller, lighter, stronger, smoother and offers much faster shifts being a sequential box (it's not an h pattern box with a sequential 'changer' so i'm not sure who gave you that advice). it will probably be easier to drive around town than a full dog engagement PAR box to be honest. the problem with gearsets like the PPG and PAR is they use the factory casing and many factory parts in which there are weaknesses. the hollinger uses none. they make a bellhousing adapter and it mates up to the factory transfer case no problem.

my advise would be sell the PAR and get the hollinger. you will not regret it. for a car that has big power and is a mix of street, drag and circuit the hollinger is a much better choice. it's a big outlay up front but saves money and headaches in the long run.

Hi Nick,

Hey sorry let me correct myself it was the PPG they didint make a 6speed gear set and that why you ha dto change the front and rear diff as its based on R33 ratio's, the hollinger when i got a quote was like the 15K plus. What i will do is ill use the PAR for now and to some tests with ii then ill switch to the hollinger.

Thank you for pointing out the mistake i made.

[BOBBYr34]

quoted for truth!

you mention not going for Vcam because 'the motor will be built with the correct cam timing and static compression this will work the same way' can you explain this a bit for me in lay-mans terms?

Well driving a GTR as you might know its very very laggy. Well have you driven a 2.5L sti if you havent well then i think you should feel how responsive it is and i know they have VCT however this RB26 is going to respond like that.

The secret lies in the cam selection that allows the correct volume to form enough energy to produce Hp that equates to response. Also the other thing you need to get right with the Rb26 is the Piston to head clearance they call it squish. This also will make the car very responsive.

John has said in the past why do you need more then one firing cycle to produce response!!! its should be done in one cycle.

What i will do is ill get a copy of some calculations and give you more a technical answer.

See attached piston design i know it says 9.5:1 comp but i need to confirm this as it is higher.

[bigmikespec]

You will have more "area under curve" with VCT; the good thing is you can vary that volume or cylinder filling time over the rpm range. This engine is worthy of VCT

[BOBBYr34]

You will have more "area under curve" with VCT; the good thing is you can vary that volume or cylinder filling time over the rpm range. This engine is worthy of VCT

I will ask the question again i know what you mean about the area under the curve i remember saying this to John 3 years ago about the VCT. I will post his reply

[mrchams]

Bob, next time you go see John I'll give you a portable HDD so you can start downloading his brain.

You think 1TB will be enough?

[BOBBYr34]

Bob, next time you go see John I'll give you a portable HDD so you can start downloading his brain.

You think 1TB will be enough?

LOL you know what its not a bad idea, ill make a list of questions from the post that people have asked and i will get hi to answer on a VID so if anyone has more questions please list them.

Thank you

[BOBBYr34]

Here is some more info on squish.

You can visit this website for more info about motor building. Look under Archive.

http://www.theoldone.com/components/

Quench, or squish area is typically the flat area on the top of the piston that's almost level with the top of the block deck. It must have a corresponding flat area on the deck surface of the head to qualify as quench.

If you look at a combustion chamber, you will usually see these flat areas, and they will have the volume of the actual combustion chamber between them. When the piston is compressing the mixture, as the piston nears the head, the flat areas on the head and piston come together and force the mixture from those areas to "squish" into the chamber, where the spark plug and burning mixture reside, so you achieve a more complete burn.

The quench area also runs cooler than the rest of the chamber / piston. These lower temperatures are where the "quench" comes from.

When properly designed, the quench areas can have a tremendous effect on the quality of combustion, and allow higher compression ratios, and due to this they are considered "artificial octane" by scientific types.

Bottom line is "properly designed, quench is good".

[NickR33]

thanks for that, really really good explanation of quench:)

I always get a bit confused when people use the word response... as I see it there's lag and then there's response... response is how quickly the car responds to throttle input when in its powerband and lag is how long (rpm) the motor takes to build positive boost and get into that powerband

so when you say responsive do you mean its going to be really quick to build boost or do you mean its going to be really responsive when on boost?

as I see it lag isn't a huge issue as long as you have a fair powerband... if your caught outside that powerband your in the wrong gear

for a street car I guess having your powerband not really start til 4000rpm isn't ideal but for a track car not really an issue... for a track car on boost throttle response, and a smooth boost transition (as it builds pressure) are king IMHO

Edit: oooh I see a 9,500rpm redline... nice!

[BOBBYr34]

thanks for that, really really good explanation of quench:)

I always get a bit confused when people use the word response... as I see it there's lag and then there's response... response is how quickly the car responds to throttle input when in its powerband and lag is how long (rpm) the motor takes to build positive boost and get into that powerband

so when you say responsive do you mean its going to be really quick to build boost or do you mean its going to be really responsive when on boost?

as I see it lag isn't a huge issue as long as you have a fair powerband... if your caught outside that powerband your in the wrong gear

for a street car I guess having your powerband not really start til 4000rpm isn't ideal but for a track car not really an issue... for a track car on boost throttle response, and a smooth boost transition (as it builds pressure) are king IMHO

Edit: oooh I see a 9,500rpm redline... nice!

Hi Nick,

This motor build will have both with minimum lag or no lag so response under full boost and response in boost. The boost we are looking at running is 64psi absolute on the turbo side and that should equate out about 34psi gauge before the throttle bodies, remember this is all calculated, we will be follwoing the laws of Joule thomson effects.

You must all have a read of the below link now you know why people run big boost rememebr when the F1 where turbo they used to run 5bar boost.

http://en.wikipedia.org/wiki/Joule%E2%80%93Thomson_effect

[SimonR32]

Air = 79% Nitrogen gas and 21% oxygen gas therefore air is a gas

I think what you are saying is a mixture of air with other impurites like unburnt hydrocarbons then it would not follow the laws of air as the viscosity will be inverted.

No doubt air is a reference to a gas, I was just saying it was a misnomer to use air instead of a "gas" or "exhaust gas"

Also remember you are burning a large percentage of the 21% oxygen in the combustion process so this would significantly change the gas properties

[BOBBYr34]

No doubt air is a reference to a gas, I was just saying it was a misnomer to use air instead of a "gas" or "exhaust gas"

Also remember you are burning a large percentage of the 21% oxygen in the combustion process so this would significantly change the gas properties

Can you explain what you have said "would significantly change the gas properties" ?

When you burn a hydrocarbon what do you get? (stoichiometric )

[bigmikespec]

Hi Nick,

This motor build will have both with minimum lag or no lag so response under full boost and response in boost. The boost we are looking at running is 64psi absolute on the turbo side and that should equate out about 34psi gauge before the throttle bodies, remember this is all calculated, we will be follwoing the laws of Joule thomson effects.

You must all have a read of the below link now you know why people run big boost rememebr when the F1 where turbo they used to run 5bar boost.

http://en.wikipedia....3Thomson_effect

Are you saying the Joule-Kelvin effect will occur when an inlet valve opens?

So 64psi (abs) so for normal people that is about 49psi "boost" (subtracting atmospheric pressure) then due to above effect it will cause a further reduced pressure at the TB to valve inlet?

[BOBBYr34]

Are you saying the Joule-Kelvin effect will occur when an inlet valve opens?

So 64psi (abs) so for normal people that is about 49psi "boost" (subtracting atmospheric pressure) then due to above effect it will cause a further reduced pressure at the TB to valve inlet?

that is correct if you dont understand it i can give you more details

[paulR32gtr]

Have you confirmed what the compression ratio is going to be Bobby?

This is definitely going to be one engineering feat! Absolutely love it - truly top level racing inspired work.

[bigmikespec]

that is correct if you dont understand it i can give you more details

I understand it no worries. Will send you PM.