dazee

Not sure if I'll go through with this yet as I may be buying an old (1849) church in the near future for converting to a residence, and that may take most my money for a while.
But if the deal falls through then I want to put money into the car, but not money that will just amplify the risks of engine detonation.

Already know from Power Enterprise that even at 420hp the engine was reliable and showed no excessive wear. So as a daily driver running it at 350hp would be no problem at all. But what about raising the power even higher, what mods would you do to ensure you have a bulletproof engine ? I mean I'll be asking Power Enterprise and a couple of other professional power companys the same, but I value the input from this forum too. There are alot of knowledgeable people here. So far my thoughts are to complement the PE twin turbo kit with the Jun Auto stroker kit to make it 3.8l, has better, lighter, stronger crank, pistons and conrods - but don't know yet if it includes stronger gaskets. Also from Jun Auto they just released a lighter, stronger flywheel for the Z33. All of this together I think would make a freer reving engine with more power and torque without losing reliability.

Other things to be added are of course a large core radiator and an oil cooler. Any other suggestions?

Also are there any benefits other than cosmetic for changing the wheels? Lighter wheels or slightly wider ones on the rear for more contact area to lay down the power ? How would it affect handling and how the TCS works etc ?

Cheers

DaZee

dazee

Not a single suggestion from anyone ???

eskimo

TCS shouldn't be affected unless you alter the overall diameter of the wheel. Wider rear tires will increase the understeer that the car already has, at least theoretically. Wider tires will definatlly benefit your drive wheel's traction, but without any other suspension modifications it will be a detrement in any application besides a drag strip.

azrael

If you want to make serious power, you need to sleeve the block. That is the most important thing you can do to strengthen the engine, followed by beefier connecting rods (which would be solved by your Jun Stroker kit.. but at an extremely high cost). The stock block's open deck is far to weak to handle serious boost. I don't even trust it at 7 psi, regardless of what Stillen, ATI, GReddy, and PE tell you.

Sleeves from AEBS, Darton, or Golden Eagle are usually rated up to 55+ psi of boost. Combined with good connecting rods, this engine should handle some serious boost.

Of course at that point, you have to worry about the transmission and differential. I doubt the stock VLSD can handle 500+ HP very long..

dazee

Thx for the info. Gonna keep the stock wheel size then as I don't want to reduce the cornering ability of the car - I'm no drag racer !

I'll look into getting sleeves, thx for that. It makes sense to do that when fitting the new pistons etc. What is the psi to bar conversion ? If you don't think the stock parts can handle 7psi what psi is 0.5bar (the max setting on the PE kit).

350Now

It's around 14.5 psi = 1 bar. If I remember correctly. Like Azrael stated. I think our block needs to be sleeved since it is an open deck designed. By sleeving the block we can take more boost and punishment.

zland

Look at the Road and Track article. The motorX car had the best laterial G's of any of the Z's. Many of the Z's had different types of suspension and wheels and tires yet the defining difference was the MotorX car had larger tires on it than the others and they were Toyos. The author actually mentioned the improved handling of it due to these issues.

Do a search for thread/discussion or just read the article which is the best thing to do. Stock lat is something like .88g vs motorx car which is .94g. That is a big difference!

Z8M

iTrader: (3)

Just for curiosity, how much money you're willing to dump on this project. Sounds mucho, mucho dinero . If I'm after huge horsepower, realiability(bulletproof) and insurance(warranty), don't you think it would be smarter just to get another car (M3. 911 T) that matches what you're looking for? Unless of course money is no object, and if that's the case why shy away from likes of superchargers (ATI), twin turbo's, N2O's,etc. and let it rock. My 2+2's

jesseenglish

Armor plating

dazee

Good question. I guess I've just always liked Japanese sports cars. Also you have to understand that here in Japan a foriegn sports car is like a status symbol. That have a huge markup on the price compared to any other country, maintenance costs are higher, they usually are as well equipped as the apanese counterparts, and every foriegner here has one You wouldn't believe the number of Porches, BMWs, Ferraris etc there are in the building where I used to work. Ether can validate that. Plus when I test drove it I knew it was the car I wanted, it is very driver orientated - much like the Toyota Supras.

So I liked the style of the car and the sport orientation. Then I got it onto the track at Motegi and got a taste of fun. Then came the test ride in the PE car and it was OMG ! And that car was pretty much stock with the exception of the turbo kit. Suspension, brakes etc were all the same as mine of in some cases less than mine. Bigger injectors and more boost and the PE kit is good for 600hp. That may be the future target, I'd ust want to get there gradually. So ensuring I have the strongest/best components to prevent engine detonation when I go that route is a must. I'll not be driving around Tokyo constantly at 600hp Just hen I need it.

So making a list of the items I'd need is the starting point. Knowing to upgrade the drivetrain and LSD etc, stuff that can be got now and installed for use later. eg the JUN flywheel is stronger and lighter than stock and would be an easy item to install when the PE turbo kit goes on as they fit a sports clutch with the kit.

When all is finished I'd have a car that handles the way I want, has plenty of power, and looks good - to me - and will hand Skylines, Porsches and Beemers their collective tails.

BTW one of the main contenders at the time of purchase was the Lotus Elise - call me a sentimental Brit - but the dealer service was terrible and put me off. If they were difficult for a sale, how would they be if I had a problem. No it made sense for a Japanese sports car in Japan with a good supply of aftermarket parts and specilist tuners.

ether

CONFIRMED

I also went with the Z because I wanted to have some fun modding it... had the M3 before and was thinking of the new M3 CSL or a Porsche... but been there done that, awesome cars but not neccesarily project cars.. this is way more fun, its all in the journey not the destination...

dazee

Couldn't have said that better meself. Had a Hayabusa motorcycle - still the fastest production bike in the World. But had great fun modding it for more power/speed. Airbox mods, race mufflers, carbon bodywork, and a new rear tyre every month ($300 a piece) even a second set of bodywork when I felt patriotic.

The journey is half the fun

Resolute

iTrader: (2)

For a more boost friendly motor, lower compression forged pistons should be the first order of the day. The cr of the VQ is too high for good boost. The SR came with 9.5:1 stock and could take only 10psi safely on stock pistons. The VQ, with 10.3:1, should be kept to the 7psi max that PE and others carry with stock pistons. After that, I think 1bar, 14.4 psi, should be just fine. Everyone disses the rods on this motor, but they look pretty damn beefy to me, slightly thicker than SR20 rods that are good for 20 psi up to 400hp on that motor. 20 psi on this beast could throw down some stupid big numbers. The JUN and TODA stroker kits are typically very high quality and well-engineered. And expensive. Stronger gaskets can be purchased from companies like HKS. I haven't heard of anyone shifting a cyllinder yet, so I couldn't tell you by what psi sleeves would be neccessary, but don't throw them in unless needed. The restrictions on the cooling system wouldn't be worth it. Most well-built open deck blocks (Honda) can take at least 1 bar without the need for sleeving, hopefully Nissan did it right. Finally, tuning, tuning, tuning. Maybe in Japan you have access to someone who can match good cams with your turbo and tune the air & fuel properly. This will be the greatest mod for reliability. As for wheels, lighter and stronger is better. Forged wheels don't "breathe" and resist strain better than cast wheels, while remaining lighter. The lighter rims reduce rotating mass and thereby cut back on parasitic loss, but more importantly, reduces unsprung weight. Reducing unsprung weight allows the suspension to do its job more effectively in keeping the tires planted, thereby improving turn-in response and overall steering quality. The size of tires should be as wide as possible. It is popular to run smaller tires up front than the rear, but for the track, I run as wide as possible all the way while maintaning proper offset. This is key, if you don't the scrub radius up front will be thrown off and mess your steering feel all up, as well as increase effort. I also run taller profiles out back just to gain a small amount of percent slip for traction and cushion over irregularities. Have fun!

Resolute

iTrader: (2)

Don't foget a lSD when either. I personlly lean to OS Giken, but Cusco makes top notch stuff, not a big fan of Kaaz, but people here seem to have good results with it.

Dissolved

Agreed. Get compression to around 8.5:1 though. Lower compression/higher boost is better than higher compression/lower boost. Look into stand alone fuel systems etc... The problem with this plan is that the rest of the car will not like a huge amount of power. You may have nothing but headaches

Resolute

iTrader: (2)

8.5:1 has proven a good ratio for pressurized motors from the factory, such as the SR20DET. I think the EJ20 has 8.0:1, while the GTi-R used 8.3:1. Just some examples to give an idea of good compression ratio for boost.

eskimo

Widening both the front and rear tires will, however, increase your cornering ability. Check out this attachment I got from BFGoodrich.com

ether

anybody have thoughts on cooling.. a couple of data points are starting to make me wonder what are the necessary mods in this area.....some "minor" cooling issues with the PE turbo kit that has been installed, the comment by the Nismo service person about heat issues regarding the R-tune ecu upgrade (still NA and in development) when somebody got the resetting package with the s-tune ecu, and TS's comments about cooling when dazee talked with them..

wondering if just a vented hood and oil cooler will be sufficient or whether an upgraded radiator should also be considered, especial for those of us in hot humid climates

dazee

They recommend and oil cooler plus a larger core radiator, especially in Japan for the humid summer time. PE does help initially with the larger oil pan that not only supplies more oil to get heated up, but also I believe has cooling fins (much like a heat sink). But everyone so far has recommended at a minimum to install an oil cooler.

Did we decide yet if wider tyres are a good thing or a bad thing ? We seem to have conflicting opinions on that point. I wonder whatthe compression ratio is with the Jun stroker kit ?

ether

If you have 245s in the back already, I think that a suspension upgrade will be more of a benefit than wider tires.. I have the nismo suspension and that has positive changed the dynamics..

wider tires and pushing out the wheels with lower offsets will also help but I would say that would be lower marginal benefit that upgrading the stock suspension... a point of reference is the M3... awesome handling characteristics.. and it runs 225s F and 255s R..

but new wheels add a lot of character to the car and if you go that route might as well get some wider tires just in case you go above 400hp... some more rubber on the asphalt for launches