L28 questions

[JMT240KGTR]

Hi Fellas,

I am going to fit flat top pistons in my L28, and in order to cater for the new parts and added compression, I'll be honing the cylinders and fitting new rings.

All other components within the motor are good, checked bearings for signs of scoring, wear etc and there is minimal if any wear at all.

It's an N42, any other recommendations you guys think could be done, or alternatively, be good to hear feedback from experience.

Cheers

:classic:

[nutxo]

oil pump and timing gears and chain come to mind immediately for me,..

mebbe have the head gone over

[JMT240KGTR]

Yeah I'll give the head a once over by a shop, inspect the chain and gears etc, i also have a 280ZX turbo oil pump i'll be fitting.

[Brett240]

If your going to hone the cylinders, put some 89 mm pistons in there.

[JMT240KGTR]

I'd fit thoase pistons if I was going to bore the cylinders,

I assume that's what you meant:classic:

[Ben]

Always replace the guides, tensioner & chain. The sprockets will probably be ok, but mileage will determine that.

Match-port the head & balance the bottom end.

(The balancing is the priority of those two)

I balanced my L24 bottom end with nothing more than a quality digital scale, an Excel spreadsheet, a bench sander & some 300-grit for finishing.

I didn't remove all the flashing from the rods & then balance, I simply removed the flashing as the balance. The overall weight would be a few grams heavier, but it was a very straighforward process & I got the assembled rotating masses to within 0.5 grams of each other(piston, pin, rod, bolts, nuts).

The initial weight difference between the lightest & heaviest was almost 10 grams....

As a breakdown, there was 1 gram between the bolt assemblies & 2-3 for the pistons & pins. The rest was the rods themselves.

[Gav240z]

Hey Ben did that make the car alot smoother? I'd imagine a well balanced engine would be really nice to drive. Better to rev etc..

Since I may be in the process of building an engine head and or block myself what can you recommend I do?

I'm really eger to learn about hot rodding an engine I have the book on "How to race and Modify you L series Engine" I've read bits do you have any other litreture I should study before diving in.

http://www.geocities.com/zgarage2001/engine.html

That site was really good help and the more I read it the better I understand it.

THanks.

[Ben]

That particular engine is still an assembled short-block in the shed.....

But it should make it smoother & happier to rev.

I looked at the how-to-modify book & basically did al the little things that didn't cost much.

(I've been studying that book for about 15 years. Originally trying to wring some more grunt from dad's L16. He fixed that problem by fitting the FJ20E)

Things to do that were easy included;

balancing, the rotating masses, de-burring the block (up to a point) and I spent about $150 on getting the head mildly ported & the sharp edges taken out of the chambers (including unshrouding the valves).

Other things that I recommend are getting all new uni's for the driveline & perhaps re-conditioning the diff if required. A nice heavy-duty clutch is also a good idea (but not too heavy)

At the end of the day it may only be a little more powerful, but it will be a better-than-stock engine.

My current L28 turbo has had no-such attention given to it. It was bought with 220,000km on the clock & received a basic re-condition, (honing & valve-grind) before being driven 3000 km more & then fitted with the T3.

I should have balanced it & given the head a bit of attention, but no matter. It seems happy enough 60,000km later....

[Gav240z]

Did you ever see Simon DeGroot's progress on his L28 240z .?

The one that was at the website zbuild.net but the site is now gone.

He did some cool stuff to that engine alright, I loved reading about it and learning from that site.

That book you've been studying is alot to take in but really captivates me I spose I'll give it a few more reads .

Thanks for the info.

[Ben]

I've chatted with Simon via e-mail a few times & my parents talked to him at length at the NDSOC nationals in Shepparton a couple of years back.

I still don't know how he's made the engine bay that damn tidy.....

[Mr Camouflage]

I've seen Simons old website. I also have the Issue of Zoom magazine that his car appeared in (Number 44 if you want to back order a copy).

Apart from bucket loads of chrome in the engin bay, he also smoothed out all the bumps, and routed electrical and fuel and brake lines inder the guards. If you look at the brake master cylinder you notice the pipes come straight down throught 2 holes drilled in the inner fender (throught grommets of course).

[Gav240z]

His car is truely awesome and the attention to detail is what I love most it shows passion more than ricey bodykits .

He deburred the block HPC coated everything from pistons to valves to anything he could.

I really enjoyed that page anyone know how to contact him?

I had his email but lost it not sure if he even uses it anymore .