- I'm here with Mark, the owner of Mazworx,
and Mazworx are the builders of their S15 SR20
power drag car.
It's recently run a 650 and as fast as 221 mile an hour
on the quarter.
Now this makes it the second fastest four cylinder
drag car in the world.
And it's run that time and that mile an hour
after only a handful of passes after a complete rebuild.
So this is obviously pretty promising and bodes well
for that S15 to take that world record
in the not too distant future.
So Mark I just wanted to spend some time
talking about some of the technology that's going
into the engines that you at Mazworx are building.
You're well known for your billet blocks in particular.
We're seeing a trend all around the world with
a lot of engines or high powered engines
are now moving away from a factory cast block
towards those billet blocks.
Can you tell us for a start, where do you see some
of the limitations in the factory cast blocks,
particularly if we talk about the SR20
and maybe the Toyota 2JZ as examples?
- OK well the biggest difference is one's a cast aluminium
and one's cast iron.
With the cast aluminium blocks,
they tend not to crack instantly but you'll definitely
see the line bore and the block actually moving around
under high horse power.
And eventually it will crack.
It's mainly the link between the head stud and the main stud
if the block does crack, that's where you'll see it.
- So you're actually talking about the block essentially
cracking through the centre?
- Yes like horizontally between the link between
the head stud and the main stud.
Now with the 2J's and with the cast iron blocks,
they'll handle more horsepower,
you won't see much of the block dancing around
because it's cast iron.
But when it yields it just ends up cracking.
- Now even before these blocks fail,
OK obviously we are talking two very different materials,
cast aluminium or cast iron,
but in both situations,
even before the blocks actually fail,
is it fair to say you're likely to see at high boost levels,
high power levels, the cylinders distorting
and hence affecting the power the engine's producing anyway?
- Well we will see in the cast aluminium blocks,
we will see the cylinder start ovaling.
You'll see that.
You'll start seeing the main caps get really loose.
You unbolt it and they'll fall out
instead of being pressed in.
If they're dowelled or they're pressed in,
you'll see that happening.
As far as them ovaling, you can make them round again.
We've noticed especially with putting a torque plates
on them, you'll see a lot of effect with that.
Initially it ovaling, and we hone them,
they'll come out round again.
- So when you've gone to the billet block,
when you're actually designing a billet block
to replace a factory cast block,
what sort of design elements are you adding
into the billet block?
Obviously you've got the ability to essentially
do anything you want.
You're starting with a solid block of aluminium
and machining that.
So what design considerations are you adding in
to improve the strength in a very high horsepower
drag application?
- Well first we'll analyse what's failing
on the factory block and we'll concentrate on that.
If you see cast iron blocks, they're iron,
but if you cut them in half, they're really thin iron.
With the aluminium they'll be thicker
but it'll be a porous cast aluminium.
So the biggest design consideration we take
is the link between the head stud and the main stud.
If we concentrate on that link and make that stronger
then it really has no place to fail.
Now as far as the cylinders keeping shape,
we'll concentrate on putting more material
around the cylinders and holding the sleeve.
We'll not necessarily make a thick sleeve
because the sleeve will hold the shape as long
as the backing is strong enough to hold it.
- Now I see that you're using Darton sleeves in your billet
blocks and you've got the option there for dry
and wet sleeve design.
So can you talk to us a little bit about those differences
where you'd choose one over the other?
- Well initially when we started designing the blocks,
we did like a pro drag block.
To where we designed it for the high horsepower,
methanol, drag race motors.
So putting water in a block wasn't really a consideration.
Well couple of years later we had a lot of customers
asking about wet blocks.
So then we kind of reevaluated what kind of blocks
we needed so we came out with like a pro street version
where it's mainly a carbon copy of the factory block
where you can run your factory roll pump.
And of course we needed water through the sleeves.
And the good thing about Darton is a lot of these blocks
already come with MID sleeves so we can use
off the shelf sleeves for those billet blocks.
Now with the case of the 2J we're working on
designing a wet block for the 2J so we're gonna
have to develop in line with Darton,
an MID sleeve for the 2J.
- So at the moment that's not a product that Daton
offer for the 2J?
- I'm sorry?
- The MID sleeve is not a product
that they offer for the 2J?
- Oh not yet, not yet.
We've already talked with them and making those
is not a problem but it'll be you know,
only one application would be for us.
Now one of the advantages as I understand it,
with using the sleeves, the MID sleeves,
is if you do in use end up damaging one cylinder,
maybe you have a lean out, maybe it nips up
or something in one particular cylinder,
you can replace individual sleeves?
- Yes that's correct, the MID sleeves have the o rings
on the bottom, they're easy to take out
and easy to reinstall,
and you just remachine it, the new sleeve.
- Now one of the other common problems we see
with very high boost import drag engines
is the limiting factor often becomes that gasket
seal between the cylinder head and the block.
So how are you addressing that,
what are the technologies you're using there
to improve that seal?

- In terms of the studs that you're using as well,
I'm assuming that you're also stepping up the size
of those studs, again being that you're using
billet material, you can do whatever you want.
Is that a big necessity when you're trying to hold
in that additional boost?
- Yeah well we first start with the blocks,
the billet blocks, we want like an off the shelf ARP,
half inch stud and they've been
pretty successful to a limit.
We have a lot of racers out there that are requesting
like a L19 stud.
So we ended up finding a top fuel stud.
It's a 9/16th bottom with a half inch shank
that we've been using for most of the guys,
and you can torque those up to 135, 150 pounds
without a problem.
But then in that case we're still running a factory cast
head so you gotta pay attention to how much
you're gonna squish the head.
If you wanna torque the head down to 150 foot pounds,
you gotta, if you're squishing the head,
then it's not really making that much of an effect.
- That was the next thing I was actually going
to comment on there.
Both with the protrusion of the liners of those sleeves
as well as the amount of torque you use.
So there is a point where more torque is
not necessarily better,
you actually start distorting the cylinder head?
- Yes that's correct.
Well with the protrusion of the sleeve,
we know that aluminium and even cast aluminium
will deflect.
So it's gonna, when we model things,
we model things as if they were a spring.
'Cause everything has a modulus of elasticity.
So when you clamp the head on the block,
it actually deforms around, the head will deform,
and the block will deform a little bit.
And the sleeve will not deform as much.
But that's where we get the extra clamping force
around the cylinder,
and like you said, if you over torque it,
you're just smashing the head,
maybe unseating the valves,
you're going backwards.
- Now just to talk about a few of the specific aspects
with the S15 drag car.
Now this is running the SR20 VE cylinder head,
quite a popular option for anyone
who wants to make a lot of horsepower with an SR20.
One of the aspects with the heads,
and this really isn't specific to the SR20,
is the squish area or squish pads in the cylinder head.
I know there's two schools of thought on the squish pads.
The idea behind them initially is that as the piston
comes towards TDC, those squish pads help
push the combustion charge in towards the spark plug,
the idea there is to help reduce detonation.
The other school of though,
that in a modified application they can actually
promote detonation and even pre ignition.
So what's your thoughts on that and what are you doing
with those?
- Well we started taking those out back in the 90s
with the lower octane fuel.
And with the SR20s, when we started building the motors,
when the customers bring them in,
they have detonation issues,
first place we see it is in the squish areas.
So what we would do is OK well let's take them out,
and we took them out and they stopped detonating,
so that was our first reason why we did it.
But after looking at it, the SR20 guys,
we started running thicker head gaskets.
So your squish area ended up being less effective
'cause you had more space there.
So it came more of a localised combustion chamber,
and that's why it started detonating.
I think with the thinner head gaskets,
and you get the piston closer to the squish area,
yeah I think it'd have a better effect.
A pent roof style combustion chamber like a 2J,
forcing that mixture up in the combustion chamber.
- So I think that comes back to,
there was an old school idea when you turbocharge
a naturally aspirated engine with a high compression ratio,
a lot of people would fit a thicker head gasket,
and while yes that will drop the compression ratio,
the reduction in that squish effect actually can
almost end up in the same place in terms
of the engine's likelihood to detonate?
- Yes that's correct.
And some of those engines like I was saying,
the 2J, even the Honda B series where you don't
have the room to take the squish areas out,
you gotta do what you gotta do.
- Now in terms of removing those squish areas,
you're also going to a bigger bore diameter,
that also has an improvement on the flow
around the valves.
You've got the ability to de shroud those as well?
- Yes, with the SR20, we go to Darton sleeves,
we have the capability of going from 86 millimetre bore
to a 90 millimetre bore.
So what we would do is we would CNC the chamber,
take out the squish areas and actually open up
the chamber to a 90 millimetre.
And we've noticed on the flow bench is actually
is helps us increase the air flow capability of the motor.
- Now a lot of people aren't doing that,
they aren't modifying those combustion chambers
when they do step to a larger bore diameter,
so obviously that's gonna introduce a step
as you come into the combustion chamber.
How detrimental is that to the engine's performance?
- Well we haven't really done any back to back testing.
But it increases your squish area if you're not
taking that out and I'm sure as you can see,
in the SR20s it'll start detonating farther in.
- Now in terms of removing that squish area as well,
machining that out of the head,
what sort of effect has that got
on the compression ratio typically?
Obviously that's going to be somewhat engine specific
but can you give us a bit of a guide?
- Well we've noticed like with the SR20 DETs
it'd take almost a full point of compression out,
and with the VEs it'd take about
a half a point of compression out.
- Alright look Mark it's been really interesting
getting some insight into that and certainly
your billet blocks are a work of art.
Also with the S15 we really look forward
to seeing what that car does next year.
Coming into winter now so looking forward
to seeing its results coming into the new summer.
And if our viewers want to find out more
about your products, how can they reach out,
how can they touch base with you?
- Well they can reach us on Facebook,
Mazworx Manufacturing,
you can go on our website, mazworx.com
They can shoot us an email at info@mazworx.com
and just search us on Google and you'll
definitely find us.
- Awesome thanks a lot for your time Mark.
- Thank you.
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