Drax240z

One of the first steps of my engine build this winter is to figure out what turbo I need to get. I'm hoping to get some insight from some of you folks, the application is autocross. Engine: 2700cc, 8.3:1 CR, Intercooled, SDS, forged pistons Target power: 300-325rwhp Desired characteristics: Responsiveness!!!! I am desperately trying to stay away from anything that builds power any slower than the stock T3. I'm hoping that the increased efficiency of the GT series turbos combined with the BB will allow me to achieve better top end power, and at least as broad a torque band as before. I am more concerned with going too large than too small!! I've been pouring over compressor maps, and have two turbo's that I think make sense, but I'd love some real world perspective from you guys. 1) GT2871R - looks like there are variants that will meet my power goals, and the idea of a smaller turbo has some appeal, even given the modifications necessary for the T25 flange. 2) GT3071R - A bit more room "to grow", but I've got a pretty good view of what I want out of this build, and 325rwhp is it... so is there any need to go this large? I'd appreciate any first hand experience you guys could share.

First, some photos of the car when I first got it. There have been about 10 years of changes of and on, put in a turbo motor and raced, drove the car daily for more than a year and a half, slowly turned it from a street car into mostly a race car with street legality. In November of 2006 the first turbo motor gave up the ghost at about 40,000 hard miles. Undergoing some changes over this winter, but here is the starting point: Chassis: 1972 240z 4pt Roll Bar Stripped interior Engine: L28 Turbo – F54/N42 8.3:1 CR SDS EM-3E Stock T3 turbo 440cc/min injectors NPR intercooler 1G DSM BOV 232rwhp/281ft-lbs @ 6psi Drivetrain: CF duel friction clutch Lightened stock flywheel (17lbs IIRC) 77 280z 5 speed 3.54:1 R200 Quaife LSD Suspension: Illumina 5 way adjustable struts (sectioned) Ground Control coilovers (225f/250r) Urethane bushings mostly Aluminum offset rear control arm bushings 1” front sway bar Front camber plates 15" snowflake rims with A032's Brakes: Vented 4x4 fronts/PBR pads Rear drums Other: Recaro seats Satin black paint

Greetings all, it's been a loooong time since I've visited, and things sure have changed around here! Lots of great changes in my life too, but the long and short of it is I am back to working on the Z! (and hopefully spending a bit more time here) In the past incarnation of my Z, I popped the motor at the end of the 2006 race season, and have been towing it around behind me ever since. After moving it and storing it in a few locations (outside) I finally own a house and am slowly getting a place to work on it. (outside, but under cover at least) It's suffered a bit from the storage, but the winters plans are to do another motor for it, along with a few other odds and ends. I've been driving a no-fun compact fuel sipper for too long. Anyway, I just thought I'd say hi. I see a lot of familiar faces still around and I look forward to seeing how you've progressed on your projects! Cheers!

Let me start by saying I've had an MSD box in my Z for 5 years now, no problems at all. But in the past ~1 year I've had no less than 5 MSD box's be the cause of problems with cars coming through my shop and running on my dyno. I'd never, ever buy one again because of that. Best I can tell those that are 2+ years old seem to be much more reliable than the newer ones. Just FYI for anyone looking at an ignition box. The Mallory, Jacobs, Crane, etc. boxes all seem to be fine.

Someone stole the photo and modified it I assume.

Dude, that wastegate position is really unfortunate. Is there any way you can use a weld-el off the bottom (center) of the 6-1 collector and attach the wastegate there instead? I'm not sure your WG is going to be able to control boost very well in its current position.

Huge improvement on my car, especially in turn in using the strut tower bars. A fully triangulated bar (to the firewall) makes even more difference than just a straight bar does. Totally worth it, front and rear, in my experience. (which granted, is very spirited street/track driving)

I took the photo, I wrote the text, and I own the manifolds. Nobody else has asked me for use of that photo.

Ooh, I want to play too.

Great info Paul, thanks for that. Just one more question, if you were ordering a cross section of lash pads to set up an aftermarket cam, what common sizes would you order?

Paul, do you guys have a good source for lash pads and rockers? Looking to order a few sets of pads and a new set of rockers... Is Nissan the only choice?

A week? I'd say an hour!

Always rwhp.

The restrictor idea can work. I found that when I had an excessively long vacuum line going to my map sensor (ie: high volume of air in the tube) that the restrictor sped up the response of the MAP sensor very noticeably, and smoothed things out. Since then, I've shortened up the line and relocated the MAP sensor which had the same effect.

Dammit, not going to make it over to the show and autocross this year... lots of representation from the island heading over though. None of our other Datsun guys seem to hang out on hybridz though, they are all wimpy NA inline cars.

Not a concern. In fact, johnc among others have verified that the N42 block is potentially stronger then the f54 block... do some searching, there are a few threads on that topic here.

I'm a big fan of the Miller Dynasty 200... check it out.

I always saw him as one of the people most passionate about their jobs anywhere, it's so rare to see someone with that kind of passion about anything, let alone a task so noble. He might not represent Australia, but I really respect the awareness of nature, especially crocidiles that he has brought to so many people that otherwise would have had no idea. The natural world lost a great ambassador and spokesman, love him or hate him.

What are the specs on those rims nazar? Looking really good!

17-19in at idle... stock cam.

Last bone stock L28 with EFI I dyno'd ended up at 121rwhp and about 135ft-lbs of torque.

It is a problem. If your helmet is hitting the bars, you might as well just drive without one for all the good it is going to do you.

If you can get away with it and still be comfortable, try lowering your seat a little bit.

I was totally against seeing it but got badgered into going... actually it was a lot of fun and in the end, not too cheesy. I'm glad I saw it! I'm usually pretty hard on movies, but I was pleasantly surprised with SOAP.

Ewww, thanks John... I guess they deem that modificationto meet the new rules is easy as their rational behind not grandfathering in old cages? I also prefer option 4.