Mistakes were made, my R34 Story

[Dose Pipe Sutututu]

CHOP IDLE TOONS

[MBS206]

49 minutes ago, Dose Pipe Sutututu said:

CHOP IDLE TOONS

I'll Chop Stick your Tuna!

[MBS206]

I also find it hilarious, everyone thinks chop idle tunes sound cool, and they do...

Because they sound like an angry rotary engine idling.

[Dose Pipe Sutututu]

This sounds beaut

 

 

[Kinkstaah]

The cam I am actually putting in (a few posts up) is actually smaller than my current one. At least duration/overlap wise.

All the chop stuff I hear just sounds like an engine running badly, because it is. I then envision driving it around in 1st gear and being massively sad about it bucking to the beat of said chop. There is an idle video of someone with a similar cam floating around the internet, but mine is a custom cam (so is his) so it'll never be the same, plus the fact exhausts are entirely different.

What I want to do is put some bullet mufflers/race mufflers in to replace a couple sections straight pipes that currently replace the two extra cats that I don't need. But this is even further down the line!

[Kinkstaah]

These arrived today!

Sadly I'm going to probably be smart and enjoy the car as is over the summer/sunny period and save the ~2 weeks downtime it'd take to swap the heads over and tune later in the year.

Maybe.

It's going to be pretty damn tempting seeing these bolt on funs just sitting in storage when they're ready to go. There's a non-zero chance I end up @The Bogan'ing it.

[The Bogan]

1 hour ago, Kinkstaah said:

These arrived today!

Sadly I'm going to probably be smart and enjoy the car as is over the summer/sunny period and save the ~2 weeks downtime it'd take to swap the heads over and tune later in the year.

Maybe.

It's going to be pretty damn tempting seeing these bolt on funs just sitting in storage when they're ready to go. There's a non-zero chance I end up @The Bogan'ing it.

God I love shiny engine parts 🥰

Are you looking for more horsetorques in the mid range? (Smaller cam) Or just more horsetorques every where? (Big heads and bigger revs)

Assumption: they were not bought late night shopping on the interwebs after drinking too many beers, which is typically how I pull pins on things......🤣

The evolution of your car is coming along nicely, I sometimes wish I didn't get bored with my cars and keep flipping them, maybe the MX5 will be different

 

[The Bogan]

Maybe not 🤪

[MBS206]

2 hours ago, Kinkstaah said:

These arrived today!

Sadly I'm going to probably be smart and enjoy the car as is over the summer/sunny period and save the ~2 weeks downtime it'd take to swap the heads over and tune later in the year.

Maybe.

It's going to be pretty damn tempting seeing these bolt on funs just sitting in storage when they're ready to go. There's a non-zero chance I end up @The Bogan'ing it.

What blows me away, is watching some of the US guys, like Tony Angelo at Stay Tuned. LS1, buys a set of heads for $1200, drops a mild cam in, pulls all the electrics, drops a basic inlet manifold with a carb, MSD thing for spark, and roll it out to make 550hp.

[Kinkstaah]

4 hours ago, The Bogan said:

God I love shiny engine parts 🥰

Are you looking for more horsetorques in the mid range? (Smaller cam) Or just more horsetorques every where? (Big heads and bigger revs)

Assumption: they were not bought late night shopping on the interwebs after drinking too many beers, which is typically how I pull pins on things......🤣

The evolution of your car is coming along nicely, I sometimes wish I didn't get bored with my cars and keep flipping them, maybe the MX5 will be different

The engine stuff is Greg Autism to the Max. I contacted Tony Mamo previously from AFR who went off to make his own company to further refine AFR heads. He is a wizard in US LS world. Pretty much the best person on earth who will sell you things he's done weird wizard magic to.

The cam spec is not too different. I have a 232/234 .600/603 lift, 114LSA cam currently. The new one is 227/233 .638 .634. The 1.8 ratio roller rockers will effectively push this cam into the ~.670 range. These also get Mamo'ified to be drilled out and tapped to use a 10mm bolt over an 8mm for better stability.

This is what lead to the cam being specced. The plan is to run it to 6800. (6600 currently). The Johnson lifters are to maintain proper lift at heavy use which is something the LS7's supposedly fail at and lose a bit of pressure, robbing you of lift at higher RPM. Hollow stem valves for better, well everything, Valve train control. I dunno. Hollow is better. The valves are also not on a standard valve angle. Compression ratio is going from 10.6 to 11.3.

The cam is smaller, but also not really... The cam was specced when I generated a chart where I counted the frames of a lap video I had and noted how much of the time in % I spent at what RPM while on track at Sandown.

The current cam/heads are a bit mismatched, the standard LS1 heads are the restriction to power, which is why everyone CNC's them to get a pretty solid improvement. Most of the difference between LS1->LS2->LS3 is really just better stock heads. The current cam is falling over about 600rpm earlier than it 'should' given the rest of my current setup.

CNC'ing heads closes the gap with regards to heads. Aftermarket heads eliminate the gap and go further. The MMS heads go even further than that, and the heads I have in the box could quite easily be bolted to a 7.0 427ci or 454 and not be any restriction at all.

Tony Mamo previously worked with AFR, designed new heads from scratch then eventually founded his own business. There he takes the AFR items and performs further wizardry, CNC'ing them and then manually porting the result. He also ports the FAST102 composite manifold:

Before and after


There's also an improved racing crank scraper and windage tray. Helps to keep oil in the pan. Supposedly gains 2% power. Tony also ports Melling oil pumps, so you get more oil pressure down low at idle, and the same as what you want up top thanks to a suitable relief spring.

There's also the timing chain kit with a Torrington bearing to make sure the cam doesn't have any thrust.

Yes I'll post a before and after when it all eventually goes together.

It'll probably make 2kw more than a setup that would be $15,000 cheaper :p