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Discussion Starter #81
Has there been another event?
I have been going to events nearly every weekend. But here is an unfortunate update:

One event when I was away my codriver drove the car and then last weekend we codrove the car again but forgot to check the oil level on our little oil burner. End result: a spun rod bearing.

So now we have roughly 30 days to get a new engine installed so we don't miss the once a year 3rd gear event at Loring Air Force Base in Limestone, Maine.

The plan is to buy a complete long block factory spec MWR engine with a baffled oil pan.

More updates to come.
 

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I have been going to events nearly every weekend. But here is an unfortunate update:

One event when I was away my codriver drove the car and then last weekend we codrove the car again but forgot to check the oil level on our little oil burner. End result: a spun rod bearing.

So now we have roughly 30 days to get a new engine installed so we don't miss the once a year 3rd gear event at Loring Air Force Base in Limestone, Maine.

The plan is to buy a complete long block factory spec MWR engine with a baffled oil pan.

More updates to come.
Ouch, that is a horrible update.
 

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Discussion Starter #89
So I have been terrible at continuing this thread since after finishing my engine swap but I want to bring it back to life with a quick summary.

So the engine was purchased from Monkeywrench Racing: Stock rebuilt longblock with updated piston/ring design. The engine shipped quickly and there didn't seem to be any damage from shipping with Old Dominion Freight Line. The motor was very clean and freshly painted. The hardest part of the swap was definitely getting the engine out and putting it back in. The reason it was so tough was because I didn't want to get a new alignment so we dropped the entire rear end in one piece (struts, hubs, axles, transmission, engine, subframe) without disconnecting axles or struts from the wheel hub assemblies.

Bleeding and burping the coolant system was a royal bitch but after 3-4 attempts it was finally air free and I quickly broke in the new engine for 20 miles and proceeded to change the oil. This all happened the day before my trip to Limestone, Maine to do the epic third gear autocross weekend at the Loring Commerce Center (will post videos later of the 3rd gear rev limiter course).

The car felt great, power delivery was awesome and this is with no tune. The drive up to Loring was smooth and I continued to break in the engine with high positve/negative cylinder pressures for 150 additional miles (this was challenging but funny to do on the highway).

At Loring after the test and tune I noticed a small oil leak coming from somewhere and pinpointed that the timing chain tensioner was leaking oil.. Upon further inspection I found that the tensioner flange was split through at one of the bolt holes. Quickly went to a local advance auto parts and picked up/installed a new one just in time for racing the next day. After that the car was great. I have yet to contact MWR about the broken tensioner, and I'm not sure I care enough about $30 to contact them..

A few weeks later at a local SCCA event the timing chain tension began leaking oil again... Had to retire for the day but luckily we had an extra tension that we had picked up from Toyota when in Maine in case the advanced part wasn't correct. Since installing the Toyota part we didn't have any more leaks through the end of the season.

The car has been great, I stiffened the rebound in the rear and it calmed down the corner entry oversteer a lot to the point where it was manageable enough to beat out some of our s2000 competition more consistently. We are still seeing a lot of inside wheel spin on right hand turns so we are going to experiment with some ride height changes on the rear right corner as well as a possible spring rate increase.

Main goal for the winter is to source an LSD. Can't wait for next season already. We still need:

1. LSD
2. Dyno tune (Camcon Ti + Greddy EMu)
3. Light weight battery
4. Lightweight wheels
5. New tires (New re-71r sizes? Maxxis 245/40/15?)
6. New spring rates?
7. Possible front sway bar

Anyway, I will post more pics later when I get them hosted on imgur. Here's to reviving my build thread :party:
 

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Discussion Starter #91
you did say 'quick' summary right?
Very similar to driving the spyder on the limit, things got out of control faster than expected.

stiffening rear rebound to calm corner entry sounds all sorts of wrong to me... i wonder if there are other setup issues that caused it
The original thought wasn't to mitigate corner entry oversteer from adjusting rebound stiffness alone, but instead to better control the 17x9s plus 245s on the rear. We were having significant driveability issues when we put the 17x9s on the rear so the thought was that with the increased mass from the heavier wheels and tires then we needed to increase overall damping. Since we were already at maximum compression stiffness the only adjustment we bad left was to try stiffening the rebound. As soon as we did that the car became significantly easier to drive.



Sent from my XT1575 using Tapatalk
 

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Very similar to driving the spyder on the limit, things got out of control faster than expected.

The original thought wasn't to mitigate corner entry oversteer from adjusting rebound stiffness alone, but instead to better control the 17x9s plus 245s on the rear. We were having significant driveability issues when we put the 17x9s on the rear so the thought was that with the increased mass from the heavier wheels and tires then we needed to increase overall damping. Since we were already at maximum compression stiffness the only adjustment we bad left was to try stiffening the rebound. As soon as we did that the car became significantly easier to drive.
I would have soften compression then rebound on the rear, along with maybe adding rebound to front. Adding rear rebound seems to make the rear of my car more twitchy so it reacts faster but your hands better be quick.
 

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Discussion Starter #93
I would have soften compression then rebound on the rear, along with maybe adding rebound to front. Adding rear rebound seems to make the rear of my car more twitchy so it reacts faster but your hands better be quick.
To be honest I haven't done much adjustments to the damping since I originally set it up. I was basing most of everything off of what I've read about settings from Koni and then just driving the car as opposed to trying to constantly change the damping adjustments. According to Koni I was supposed to adjusted compression until the tires started to chatter when they lost grip and then back off by 2-3 clicks. The front worked out fine that way, but the rear reached maximum compression stiffness without that happening. When it rains however they both chatter tremendously because in that situation they are overdamped. However I don't like crawling under my car in the rain so I generally leave compression the same. Rebound however I should probably mess with a little more to try and make the car feel more stable ¯\_(ツ)_/¯.

I've always had the thought that tuning the way the car handles should be done with springs/swaybars and ride heights more so than with shock settings. But there are definitely some adjustments to be explored.
 

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To be honest I haven't done much adjustments to the damping since I originally set it up. I was basing most of everything off of what I've read about settings from Koni and then just driving the car as opposed to trying to constantly change the damping adjustments. According to Koni I was supposed to adjusted compression until the tires started to chatter when they lost grip and then back off by 2-3 clicks. The front worked out fine that way, but the rear reached maximum compression stiffness without that happening. When it rains however they both chatter tremendously because in that situation they are overdamped. However I don't like crawling under my car in the rain so I generally leave compression the same. Rebound however I should probably mess with a little more to try and make the car feel more stable ¯\_(ツ)_/¯.

I've always had the thought that tuning the way the car handles should be done with springs/swaybars and ride heights more so than with shock settings. But there are definitely some adjustments to be explored.

That is a good way to adjust front compression. I can't say that I have ever heard of anyone doing the rear that way. I know if I hear chatter the compression needs to soften up. Shocks are used to tune when the car is moving, springs and sways can help tune that too for say role rate, but tuning that spring balance is more for stead state balance. I know I changed spring rates when I was waiting on front or rear to catch up to me through a slalom. Maybe some of those spring changes help with corner entry. Corner entry as you described seems more like a shock issue and overloading the tires by transferring too much weight too quickly. I also think I may have learned several band-aid fixes to address issues when other options were not open for Stock classes. That makes setting up the suspension in STR a bunch more difficult, i.e. need to change springs when shocks can act as a band-aid.
 

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Discussion Starter #95 (Edited)
Quick update:

As the new season approaches the last minute scramble to get the car ready is underway.

I recently installed a new transmission with an OS Giken tuned by Black Watch Racing. Very excited for this coming from a stock open differential.

New 6uls are here, just need to have the tires mounted. 15x9 fronts and 17x9 rears. Tungsten of course ;).

Shoes will be Rival-S 225/45/15 in front and 245/40/17 in the rear just like last year. However I did get a set of the new Maxxis VR-1s in 245/40/15 all around. I will be using this mainly for street driving but will be doing some testing at events hosted by some of the less competitive (non-scca) clubs locally. Fingers crossed that they will fit no problem, and I will be posting soon to update on that topic. They are going on some TRM C3M wheels, 15x9 +36.

More things for this season, hopefully sooner rather than later:
-Dyno tune for 93 octane using Camcon Ti and Greddy eMU
-Lightweight battery
-Possibly sway bar/spring stiffness experiments
 

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Discussion Starter #96
So I finally attended my first ProSolo at FedEx Field in DC.

Some points I took away from the event:
-The ProSolo format is so much fun and adds that extra piece to the competition
-The course was way too open with a 400' straight away up a hill at the beginning (not spyder friendly)
-Having different conditions for every run heat is a challenge

Leading up to this event I was inspired to come up with a GoPro mounting solution which I am very pleased with the results. I also played with the Protune option in the Hero3+ black edition which yielded some great quality footage (be sure to watch it in 1440p).

I definitely left time on T1 on both courses, as well as a bit here and there due to some brake lock up and fear of spinning magnificently.

For your viewing pleasure:
 

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Discussion Starter #97
Hey all,

Just wanted to bring this thread back to life before I forget and speak to my departure from STR in the spyder. I am making the jump to CSP and basically did my first event ever as CSP at Solo Nationals this year in Lincoln.

The car was a blast but definitely needs development. So far it's basically just my STR build with spring changes and a front and rear sway bar. The car is lifted up a little bit, the fenders are cut, and I have 275/35/15 A7 Hoosiers on all 4 corners. Pinched on a 9" 6ul up front and on 10" 6uls in back.

I will update this a little later but I'm already swapping spring rates around as I haven't found the right numbers yet.. :party:
 

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Discussion Starter #99
Thanks for the update. What was the major reason switching from 17s in the rear back to 15s?
Tire sizing and cost mostly. I am experimenting with the 15s and 275s and will see if I am just all over the rev limiter or not. I can get my hands on take-offs from other CSP miata drivers pretty easily so I currently have 3 sets of 275 A7s.

Also going to a 17" wheel with big boy A7s will likely be a lot harder fitment-wise and a lot more expensive too. We'll see how it goes, but as the car currently drives I'm struggling with understeer. Made some significant spring rate changes at the last even which seemed to help a bit, but I still am struggling to get the transitional rotation I'm looking for. More testing for the last few events this season but I am probably going to buy new suspension for next season.
 

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Discussion Starter #100
Another CSP update since I will be making a lot more progress on this build this coming off-season and next season I should be hitting it full force:

I have been waiting all summer with some delays for my new suspension I spent a lot of time sourcing and holy s*** am I happy with it! I ended up ditching the homemade Koni double adjustables shown in the beginning of this thread (which can be sold if anyone is interested) and decided to get some RedShift Motorsport Competition Coilovers, Double Adjustable with Remote Reservoirs (Chris at RedShift is an amazing guy and knows how to build one hell of a capable autox coilover. Singles w/ no remotes available too! https://store.redshiftmotorsports.com/RedShiftCompCoilovers-s/147.htm).

After installing his coilovers the car completely transformed into an amazing and capable machine. Transitions and turn-in are so crisp and immediate. The car holds so much grip and sweeps like crazy. Just keep feeding in throttle coming out of the corner (sometimes before the apex too) and the OS Giken comes to life and the car just keeps gripping. Anyway enough swooning, here are my current spring rates and bar setups since I wasn't able to figure out how to edit my first post:


Suspension - RedShift Motorsport Competition Coilovers - Double Adjustable w/ Remote Reservoirs
https://store.redshiftmotorsports.com/product-p/red-race-valved-series-double.htm

Front Springs - 350 lb/in
Rear Springs - 600 lb/in

Front Swaybar - Whiteline 22 mm
Rear Swaybar - Whiteline 18 mm


Ride Heights

Front - 1.0" lower than stock (measured from ground to front-most control arm mounting bolt to chassis)
Rear - 0.6" lower than stock (measured from ground to front-most suspension link mounting bolt to chassis)


I decided to go with a more traditional setup for CSP than I did in STR with the addition of sway bars and a rear-biased ride frequency:

Ride Frequencies

Front - ~2.7 Hz
Rear - ~3.0 Hz
Bias - ~10% rear bias


The car on it's first event with the new suspension and setup was absolutely amazing and surpassed all my expectations. I only have two more events this season but I plan on trying to test out returning to 17x9 rear wheels again with 275/35/R17 Hoosier A7s to get some more speed out of 2nd gear. At my last event I spent more than 50% of the course at WOT on the rev limiter (raised to 7200 rpm).

With some math that comes out to be just shy of 59 mph which is way too slow to be nationally competitive imo. Switching to the 275/35/R17 A7s I should be closer to 63 mph at limiter which is more usable. I think these coilovers will be totally fine dealing with the additional unsprung mass, they can get very stiff.

Expect to see a front splitter/air dam and rear spoiler made over this winter. I do plan on trying my luck at some composites of the carbon fiber variety 🤓. I do plan on keeping this thread more active in the coming months so stay tuned.


- e1
 
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