Jump to content
HybridZ

L series dimensions - Stroke, Bore, Chamber cc's, etc


Recommended Posts

  • 1 month later...
  • Replies 48
  • Created
  • Last Reply

Top Posters In This Topic

  • 3 months later...
Tim,

 

Happen to know what page you referred to? Maybe it is under a new web address? Thanks.

 

It used to be a much-referenced sheet of head/piston/rod combos for various L-series engine build options.

 

For some reason, it appears that ZClub of Texas has removed this valuable piece of reference info from their site. I think "Mad Mike" Taylor is a member here, maybe he could shed some light on this...

Link to post
Share on other sites
  • 2 weeks later...
  • 1 month later...
so a LD28 crank into a L28 gives a stroker with:

86 x 83

 

Using http://www.online-calculators.co.uk/volumetric/cylindervolume.php (my maths sucks without a fancy calculator, better than the MS windows build in calc) to give a cylinder size of 482.32485714285673 then multiplying the result by 6 for number of cylinders gives: 2893.9491428571405

 

or close enough to 2894cc. 2.9 litres.

 

Yet I all a read on this forum in terms of stroker builds are 3.0 or 3.1 not 2.9

 

do the strokers also get bored out, or does installing the LD28 crank into L28 do something I'm missing from the straight bore x stroke lists here?

I was wondering the same thing as well. How come I never hear about a 2.9 liter?

 

Also On the calculater on the link earlier, according to it, you can only run l20a rods with and ld28 crank in a l28et block. Some people have speced their engines to run l24 rods with the ld28 crank in the l28et. Is the calculator wrong? Or is it because you have to modify the pistons?

 

On the calculater it acts like l14/l20a rods are the same, I have read other threads that claim them to be very different-the l14's being more ideal for a stroker setup.

 

Someone clear these things up! I'm becoming confused.

Link to post
Share on other sites

The calculators aren't 100% accurate.

 

L28ET block is the same as the L28E block

L14 rods = 136.6mm

L20a rods = two different lengths 133mm and 135mm depending on year

The 135mm L20aE rods have smaller big ends and piston pin ends just like the late L24E here in the states. They're weaker in general, so they should be avoided for performance applications.

There are no 128mm L series connecting rods.

 

There is a lot more involved in choosing a piston and rod combination than just punching up a combination in one of the L series calculators.

Link to post
Share on other sites
Ideal for what? Rod/Stroke ratio?

According to the calculater it is ideal to have a shorter rod to allow for a longer stroke to prevent the piston head from protruding over the head gasket. So 130mm being the shortest of the options(noting that you say 128mm doesnt exsist), it would make the l28 rods ideal.

 

Or am I totally off?

Link to post
Share on other sites

I think you're a bit off (not you personally, just on this one subject). You might want to do some searching and google around to find the benefits/disadvantages of long rods and short rods. You also have to factor in piston pin height and availability of said pistons. If you have any more questions about a stroker build it might be best to start your own thread.

 

To try and keep this thread on focus, the L28 rods have a center to center length of 130.35mm, not 130mm.

Link to post
Share on other sites

and you never hear about a 2.9 liter because most people building the stroker, are using the LD crank, L24 rods, and KA24 pistons, which line up at the right deck height, and are 89mm bore, so boring the block is kind of standard anyhow. This nets you ~3.098L.

 

Bore a stock 280 to 89mm and get custom pistons, and you have ~2.949 liters. Push it to 89.5 and you are up to ~2.982. Those pistons on a stroker assembly would have ~3.133L. but that bore is REALLY hairy regarding cylinder wall thickness. Many say "no way." Point is, there is more difference between the stroke of an L24 and the stroke of an L28, than there is between the stroke of an L28 and that of an LD28.

 

Also, you'll notice that every time I quoted a displacement, it had one of these jobs in front of it~~~~~ That is because I was lazy and used the calculator. Calculators cannot build engines using facts from the internet, or a book, or anyone. People build engines using machines to measure, size properly, and assemble. Even taking a factory fresh engine apart and rebuilding it to stock specs for a stock race motor, every thing is checked, spec'd, and all math is done.

 

If you use a calculator, even a SUPER GREAT ONE, it is an estimate! If you do ALL the math yourself, but the numbers did not come off the dial indicators for YOUR ENGINE parts, then you will end up with an ESTIMATE. That cannot be stressed enough.

 

The calculators are great things, handy to have around. For Estimating.

Link to post
Share on other sites

So you could bore and stroke a l28et put

 

KA24 90.5mm bore pistons

F54 block-overbore 4.5mm

LD28 crank

L24 rods

 

You could get 3.2~L high compression 9:1 engine out of this setup? Run a large turbo and you should be set for some high hp numbers. (thats of course with some head porting, ITB's(Individual Throttle Bodies), larger injectors, haltech/aem/wolf ecu,... etc)

Link to post
Share on other sites

You'd be very lucky to find a block with thick enough walls to support that size bore. If you search you will find threads that cover wall thickness and sonic testing as well as acceptable wall thickness for turbocharging.

You likely wouldn't be using a L28ET F54 block though. You'll find that out with some searching.

Link to post
Share on other sites
  • 4 months later...

I have read most of the thread and maybe I missed it (dish cc's)

 

I just bought some 90.3mm forged pistons with a 10cc dish...does anyone know what the L28 Turbo pistons are.

 

PS What head gasket can I use. Or can I open up the stock gasket...Most aftermarket companies (HKS) don't offer them anymore.

Link to post
Share on other sites

×
×
  • Create New...