Hey eage. Ever thought about a twin turbo setup for autox?

 

yeah, eventually... that is just a lot of money to lay out and isn't really in the cards at the moment....

turbo
manifold
wastegate...

it adds up fast

that and if I were to go single turbo I'd want to get something really nice like a Garrett GTX which makes it even more expensive.

currently I'm just planning to changing from my current boost controller (greddy profec b spec2) to a megasquirt controlled valve to hopefully make the turbo spool up a bit quicker and make it a bit more manageable at part throttle.

current smaller ball bearing turbos work almost as well (if not as well) as older style twin turbos without all the crazy complication. I'd rather just go GTX30R or something and tune the boost control (possibly with a 4 port mac boost control valve) to make it spool really fast.


The next thing on the list of things to do is to get it tuned a bit better, change over the boost control to megasquirt and then start adding aero

I also have a a package full of goodies that I mentioned earlier on it's way than isn't here yet

 

I'm cleaning out the garage if anyone is interested:

https://www.rx7club.com/2nd-generati...n-out-1044508/

 

So I had some time to wrench on the car a bit tonight... found some interesting things...

First I tested the fan relay a few days ago, and it's fine, so it's either the switched 12V or the megasquirt grounding it... I need to hook my laptop up to it and see what the ms is up to, the 12V looks fine.


I took the oil cooler off, rotary extreme is sending me an additional kit to move the oil cooler to the front of my radiator. hopefully that'll fix my oil cooling issues. While I had the oil cooler off I also replaced the oil thermostat with a new mazda piece... it can't hurt.

I checked the exhaust nuts, a bunch of them were really loose which is probably the cause of my exhaust leak, I tightened all the nuts I could reach up, hopefully the manifold -> engine nuts I couldn't get to are ok.

I also noticed the circlip fell off my wastegate actuator and it wasn't even connected anymore.... there's the cause of my low boost I think after I took my turbo apart to insect it I replaced the circlip with one that probably wasn't exactly the right size (probably SAE). anyone know where to get a wastegate circlip? I replaced it with a snap ring thing... (not really sure what's its called, but it's a conical button type thing that goes on easy one way but doesn't come off easily.... it's also a bit too big, but it should hold it for now. I'll keep an eye on it.


lastly one of my sway bar endlink bolts seems to have jump ship... no where too be found. that explains why the car was rolling so much in this picture:


I lost the bearing spacers which is annoying... but I replaced them with some of the ones off the rear mazdatrix kit I had lying around (since I took off the rear sway bar)

 

The package I've been waiting for finally arrived These will be my new autocross wheels. The 18x10.5 Enkei RPF1s just aren't wide enough

18x12 +20 Rota P45R3:





Put them on the scale this morning and they weigh in at 23 lbs each which is about the same as 3 peice CCWs that cost 3 times as much.

It'll be tight in the front... We'll see how it goes

 

holy S*%&t those are big, you're going too have a really hard time getting the 195's on there!

 

take them to a mexican tire shop and i bet they could find a way.

 

sickkk!

 

lol, the plan is to run the same 315/30/18s I currently have on the front (just on the edge of the "recommended" wheel size from hoosier) on the rear I have a friend with a dead 335/30/18 that I'll be test fitting... but until I can find some used 335 r-comps for cheap, I'll be running 315s in the back too.

 

 

Nice selection, let me know how those wheels work out!

 

The test fit is looking pretty promising:



I ended up having to add 30mm of spacer so they're currently at a -10 offset. not ideal, but it is what it is.

 

scrub radius measured in feet ;-)

 

don't hate

what offset are you using on the front? even with the 18x10.5s and 315s I could only manage a 0 offset.

at this point my scrub radius is 2" away from the stock wheel... I'm not sure what the scrub radius on that is though, but my increased SAI fixes some of it... so I don't think its too bad...

 

The "rule of thumb" that I've heard is that you want the scrub radius to be about 10% of the tire width.

 

What are the specs of the rpf1 wheels? Do they have a home yet?

 

They are 18x10.5" +15 19 lbs each.

I'm not sure if I want to sell them yet or not, but if you're interested make me an offer. They've been autocross wheels their entire life and only have like maybe 10 street miles on them.

 

at this point my scrub radius is 2" away from the stock wheel... I'm not sure what the scrub radius on that is though, but my increased SAI fixes some of it... so I don't think its too bad...

This is what I was thinking too. You should measure your scrub radius for us!

I agree going from stock 0 to -1 camber up front to inclining the struts several degrees more (-4 to -5 degrees camber?) and increasing tire outer diameter should help bring your scrub radius back down.

 

scrub is a super pain to measure We'll see. I don't think it's horribly bad, so the only thing measuring it would give me is to just know what it is

I'm only running -3.5* of camber. and I don't really want to run anymore so I can avoid jacking issues with the large wheels/tires. plus the camber plates are now maxed out so any more camber would have to come from extending the ball joint. slotting strut ears doesn't increase SAI.

also, the 315/18s are only 25.6" tall so 0.6" taller than stock. .3" extension per side probably doesn't do much of anything to that scrub radius...

 

Nice project ! . i'm just love to se people tuning their fc's

 

plus the camber plates are now maxed out

You might already be employing this trick, but if your camber plates are thick enough/made thick enough you can push the strut over so the nut or even the strut shaft interferes with the hole in the body instead of some part of the pillow ball carrier.

If at some point you decide you need more camber with little work.

slotting strut ears doesn't increase SAI.

Yes. Conversely, you can increase your SIA at the strut top and take camber out at the strut mounting ear to decrease scrub radius.

 

Darn they are quite a bit more aggressive than what I wanted. I need some track wheels for the rx8 on a stock body.

 

Yeah, I know a few of MR2 guys that go pretty crazy with that kind of stuff....



I think -3.5* is fine for now though, I have a tire pyrometer that I'll be verifying with.

That would allow me to run less offset too... but I think it would start doing some pretty wonky things with jacking... too much SAI is bad even if it lowers the scrub radius. I think it's fine for now.

 

Oil Cooler relocated to the front of the v-mount:

 

Are you still running a single oil cooler?