DLJ's build thread

[lpmagruder]

I'm with you on the rear tubs. My car is almost complete and that has by a decent margin been the most frustrating and time consuming part. They still don't fit well, I hear them banging around like crazy when I drive so there's some trimming I still need to do, and I plan to add some more support/triangulation to keep the big flat areas from vibrating.

[idf]

I'm with you on the rear tubs. My car is almost complete and that has by a decent margin been the most frustrating and time consuming part. They still don't fit well, I hear them banging around like crazy when I drive so there's some trimming I still need to do, and I plan to add some more support/triangulation to keep the big flat areas from vibrating.

Consider the mounting tabs from Zero Decibel Motorsports.

[driveslikejehu]

Consider the mounting tabs from Zero Decibel Motorsports.

I wasn't aware of that; it's a good idea. Thanks

[driveslikejehu]

Quite pleased with the car’s first outing, an autocross in an old ¼ mile banked oval in Rockford Il. First autocross in a few decades but took a good suggestion for a shakedown before a track day in a few weeks.

So far, handling seems okay. I was concerned about and tried to induce snap oversteer with a big lifts mid-corner. The car was like, “Yes, and…?,” wasn’t bothered. Has the expected push on corner entry but neutral thru the corners; steerable with the throttle like my Cayman.
And it’s a hot rod… When the boost comes in- with lots of whooshing noises- it gives a nice taste of power-to-weight ratio.

But mainly… nothing fell off, nothing smoked. Beyond a small yet to be identified coolant leak. Still needs work on the brake bias; the rears have barely scuffed the rotors.
And it’s a crowd pleaser; everybody stops by to check it out…
glam 1.jpgauto-x 2.jpgbanked 2.jpgbanking.jpg

some in-car on Youtube
https://youtu.be/docdrIc-SYs

[driveslikejehu]

Finally got the 818 on the track. First real drive after a year and half build.

First, my setup:
Stock 2006 STi drive train, all electronics and all 4 corners
Falken RT-660 tires; 215/45-17 and 245/40-17
Springs: 400# front/ 300# rear; running 17mm front sway bar

818 on track.JPGRFA.JPGtrack int.JPGwave.JPG

First impressions: Its a racecar; its stiff, raw, lots of NVH, but lots of go. Easily hitting speeds on the straights comparable to my Cayman, though laps time were much slower as I’m trying to learn it and not push too hard. Fun to heel and toe once again.

Learnings/ things to fix: My temporary IC air flow was inadequate. I have a 2 sensor IAT gage and “cooled” air wasn’t much cooler. I’m working on scoops and better ducting to get air to/thru the IC, but didn’t get them finished. Then we’ll see if another option is needed.
Shifting got tight, locked up. I’ll post more detail in the trans section. https://thefactoryfiveforum.com/show...fter-locked-up

Handling was pretty great. I’m still getting use to the idea of no nannies, but every drive builds confidence. I noticed definite understeer turning in to corners at first. This seemed to improve when the tires got a bit of heat. Thru the corners seemed very stable, plenty of grip. Any power oversteer seems modest and controlled, though I wasn’t really booting it out of corners.

Brakes are strong but need more rear bias. I used about half the adjustment in the Wilwood dual MC setup and a turn or two on the proportioning valve, but still lock up a front on occasion. Rear brakes aren’t in the game much.

Cooling seemed adequate. On a sunny 92deg day I never got the temp gage in the stock dash out of the middle. I plan to verify if this working properly but seems to be. Oil temp got to maybe 240. Not too concerned about this but I’d like to hear thoughts on it.

Overall successful first outing I think.

[driveslikejehu]

I’ve been working on IC scoops that go where the stock ones did, are a bit bigger and can help to clean up the awkward area caused by the R rollbar.
I cut off the forward reaching arms of the engine cover and used these to build on. I glassed on a floor and some side pieces, then started making the shape with polystyrene foam. This stuff works well with the epoxy and glass.
rt scoop 1.jpg
rt sccop 4.jpg
rt scoop 2.jpgrt scoop 6.jpgPXL_20230618_185248536.jpg

When I got pretty close to the shape, I added 2 layers of 6oz glass. I cut out the pink foam with a repurposed long filleting knife.
PXL_20230726_141240251.jpg

I added brackets on the frame and upper side area as shown with yellow arrows. I worked out a way to attach the forward side end of the engine cover with a dzus fastener that is reached down in the scoop.
scoop brkts w arr.jpgun dzusd.jpg rt scoop fit.jpg

Pretty happy with how this is looking and early testing suggests I’m getting decent delta-T thru the IC. Next track day will really tell the tale on that.

[driveslikejehu]

After application was 8 weeks in the bureaucracy, the State Police came and inspected my car. Approved! Got the Illinois VIN to prove it. Easy peasy; the only thing that had me worried was how the parking lights don't get enough volts unless the engine is running. He didn't ask, so okay...
9-12-23.jpg
SP 1.jpgVIN not.jpg

[blomb11]

Heck yea that is awesome congrats! And secretly super jealous

[driveslikejehu]

Heck yea that is awesome congrats! And secretly super jealous

Thanks! The benefits of being retired; plenty of project time

[FFRWRX]

Very nice work on those scoops!

Maybe tape some strings in front of them and go for a drive just to make sure air is flowing in. I remember reading that the rear/side scoops on the original Cobra Daytona worked in reverse due to the windshield causing a huge dead spot. They added the deflectors to the sides of the windshield to keep the airflow attached.

[driveslikejehu]

Got the tags and title in the mail! Just in time to take the wife out to celebrate our 35th anniversary.
1st drive.jpg
Just like a real car...

[driveslikejehu]

Don't know if I need a splitter, but I did need a winter project I could do in the basement. Plywood core with 2 plys of 6oz glass epoxied on either side. Didn't try to make it perfect as I expect it'll get damaged.

sptr bot glass.jpgsplt top.jpgslptr 2.jpgspltr 1.jpg

[blomb11]

Looks awesome!

[driveslikejehu]

I decided to make a diffuser to partially close off the parachute like rear bumper. Made the mold using insulation foam and plywood with a couple of layers of epoxy filler. Then laid it up with 2 layers of 6oz woven around 2 layers of mat. Very flexible but came out pretty well.
PXL_20240329_150232705~2.jpgplug.jpg,on mold.jpg,diff qtr lw.jpgdiff rear up.jpg
Now that its warmer, time get back in the garage.

[blomb11]

Nice! I want to do the same thing rather than buy the FFR one which they probably don't sell anymore anyways.

[driveslikejehu]

I've been waiting on warmer weather to do some testing (yes, in Chicagoland that means late April). I could see that I was getting about 30* temperature drop across the IC, but wanted to make sure the scoops are doing something. We'll I'm not sure what's happening, but I'll take it.
The first test showed air coming up from the side of the car, heading to the scoops, but very confused flow at the inlet.
flow lft 1.jpg
But as noted, under boost I could see a good temp drop. I thought either flow is confused at the surface, or air is coming up around the engine and stopping the scoop flow...?
Anyway, I ended up adding 4" flex ducting to see what woud happen. Also added a couple of tufts in middle of the opening.
flow pic 1.jpg
ducts.jpg
In the area in the white oval flow seems very confused or even reversing. Over by the inboard wall it seems good; blue arrow.
Putting around I see a little temp drop. Under boost in that last configuration I get better than 40*. I'll take it.
low boost.jpg hi del t.jpg

[driveslikejehu]

First full track day and wow! Lots of grip, plenty of brakes and great torquey power. It is a very participatory experience. Have to work a lot harder having fun than in my Cayman. And like the Cayman, the car has more capability than I do, so it pulls you along.
For reference, mine is an 818R, street setup, using a 2006 STi donor; stock engine and drive train. The only aero I have is a homemade splitter (grass cutter) and sorta diffuser.
Other than one off due to poor brake balance, no issues noted. Good cooling, oil temps stayed in line, no low oil pressure warning.
It will take more track time to figure out what to tweak next. I didn’t notice any odd behavior. My IC scoops were less effective than on the street, but I have more than enough power for now. Like the man said, before spending the next thousand dollars on the equipment, learn to drive faster.
BFR w drvr.jpggrassy.jpg
Youtube link to my "off": https://youtu.be/9DNGw06aMS0

[driveslikejehu]

Another track day; more development.
I think I’ve settled on an Intercooler air flow system. The scoops I fabricated in place of the standard FFR worked around town but not much at the track, even with dedicated ducts. Following inspiration in some old forum posts, I added pusher fans to the IC. I wired them to the ACCY relay using an unused Subaru switch.
IC fans.jpg
Now I’m getting a good 60+deg delta when pulling down the straight. IC inlet about ~200* and outlet about 135*. A little testing in the shop showed the fans pulled air from the scoop area- and wherever else. Sorry for the low rent “data acquisition.”
ait gage 4b.png
After my shifting locked up last year on a hot day, I suspected heat- though never understood why/how. I installed a heat shield between the exhaust/cat and transmission. A doubled it for grins and radiation transfer thoughts. This time I saw reasonable trans temp- never above ~150deg. Using an IR probe, I measured 460+ on the exhaust side and ~170* on the trans side of the shield.
Exh shield.jpg

Still getting use to the car; learning to trust the grip and balance. This time I really noted turn-in is very impressive; I find I can always tighten the line. The front seems to stick like crazy. Never any understeer.
Mid-80’s and no cooling or oil pressure issues.

[driveslikejehu]

Unloading after last track day, I noticed I could hear the turbo spooling up and down; hadn't noticed that before. Also, some rattling in exhaust area. I pulled the downpipe off to see how the cat looked, and... its all gone! So I guess sorry? for spraying folks with cat bits?
I've had no comments about loudness with just the cat, now it's a bit louder, not much. I'll see how long I can get away with it...
no cat.jpg

[Bicyclops]

At least it wasn't in the up-pipe. I bet you would have really noticed new turbo noises.

Ed

[driveslikejehu]

At least it wasn't in the up-pipe. Ed

Some have a catted up-pipe? Yeah, Cuisinart

[Bob_n_Cincy]

Some have a catted up-pipe? Yeah, Cuisinart

I'm running a catted up pipe and a catted downpipe on a 2.5L TD04 turbo and no muffler. I meet the sound requirement at NCM Motorsports park. It is quiet enough for the street as long as I keep my foot out of it.
If mine goes it will give me an excuse to go to a bigger turbo. Probably go to a stock STI vf39 or vf48. Then get it tuned for 300 WHP. If I remember correctly I'm about 195 WHP now.
Bob