With the gas tank out, I have a few pieces to remove so I can finish removing the insulation pad from the firewall so I can paint the engine compartment. Ordered the stock black metallic paint from 1986 in spray cans and clear coat for the engine bay. Any suggestions to dye the insulation pad back to black?
Great ideas here- bearings in your gol dang shift linkage.
Thank you for the info. That gets me right where I need to be.
club 4AG suspension link
They're recommending around 550 lb/in for rear springs, 225 lb/in front. The article makes it sound like they know what they're talking about.
lxnm
New Reader
5/7/20 8:25 p.m.
In reply to wheelsmithy (Joe-with-an-L) :
Huh, that's interesting, they're essentially suggesting rear springs twice as stiff as the fonts and the swaybar stays in. This is interesting because if you look at the STS development thread for the AW11, they also come up with a 2:1 ration (700 and 350 lb/in springs) but the stiff ones go up front and the swaybar is removed. Note, that thread is stupid long, and the setup is for track not road use. Internet wisdom sure is something.
In reply to AWSX1686 (Forum Supporter) :
This is like working on a 5 or 10 year old car that was garage kept. No body rust, everything is clean, only rust was in the gas tank from sitting with bad gas for many years.
lxnm said:
In reply to wheelsmithy (Joe-with-an-L) :
Huh, that's interesting, they're essentially suggesting rear springs twice as stiff as the fonts and the swaybar stays in. This is interesting because if you look at the STS development thread for the AW11, they also come up with a 2:1 ration (700 and 350 lb/in springs) but the stiff ones go up front and the swaybar is removed. Note, that thread is stupid long, and the setup is for track not road use. Internet wisdom sure is something.
I remember that thread from years back and was involved to a small extent (different username). I'll just say that it was largely driven by Steve Holescher (sp?) suspension theory and he didn't/doesn't follow the conventional wisdom that the heavy springs go on the heavy end. It appears to work pretty well on course, but it doesn't look street friendly.
It does sound very much the reversal of conventional thinking. Since my car has the supercharged E51 transmission and the 1MZ-FE V6, I am leaning towards the club 4AG article's thoughts on softer front springs to let the front squat under braking. I may have found a set of Ground Control coilovers, front camber plates with Illumina insert. Waiting to find out what the spring rates are, but this might be a good solution if the spring rates are decent.
edmagoo
New Reader
5/10/20 2:40 p.m.
I have found that the MR2 does like to have the front suspension loaded before full brake force is applied. If the front springs and shocks are soft, it's possible to lock the wheels by applying the brakes too quickly. Stiff springs or stiff shocks will shorten the time needed to get the weight onto the front suspension. Otherwise you need to develop a smooth brake progression over half a second or so to get really extreme deceleration.
As usual, everything is a compromise between comfort and performance.
I believe those STS development threads over at MR2OC are good reading but I also believe that the author might be right for the wrong reasons (just my opinion), so it may be difficult to extrapolate his conclusions. It appears to me he has developed a predictable racing setup that can be easily fine tuned by changing roll centers with small changes to ride height. Not necessarily useful for the street or dual track/street use.
In reply to edmagoo :
I think you're right about needing to manage front weight transfer during braking, but I'll add that the stock system's excessive front-bias is also a big factor. A proportioning valve helps without relying on springs/dampers entirely. I think Toyota was already worried enough about the general public's ability to drive mid-engined cars that they went very conservative with the bias.
In terms of Steve being right for the wrong reasons - care to elaborate? I'd love to hear your thoughts on that.
I have decided to start with the Koni Sports and the Eibach lowering springs as the starting point and can then make changes from there. I need to find out the total weight and front/rear bias before changing anything drastic in regards to spring rates.
I have the Koni/Prokit combo on my AW11. As a street setup it's a great compromise. At autocross turn-in is fine, but it tends to understeer during steady-state cornering with the stock sway bars and a conservative alignment. The car could use more rate overall in that environment, but that's not what those springs were designed for. Overall I can recommend it, but I'm starting to get curious about other setups.
Of course, YMMV with a little more weight in the back and twice the power.
Thanks for confirming this is a good starting point, it seems to be the "go to" suspension upgrade short of coil overs. The car will have Prothane bushings, all new suspension wear items (ball joints, tie rod ends, etc). The rear suspension pieces are from an 89 Supercharged car, so the slightly different rear geometry. I have the front sway bar and the supercharged car's rear sway bar I can add as well. Won't really know how it handles until I get it all put together, as you said it will probably weigh the same as a supercharged car with the heavier transmission and V6. The rear suspension changes after 86 were supposed to tame some of the snap oversteer tendencies, but with more weight in the rear, my car may overcome that.
edmagoo
New Reader
5/13/20 10:11 a.m.
Matt B (Forum Supporter) said:
I think you're right about needing to manage front weight transfer during braking, but I'll add that the stock system's excessive front-bias is also a big factor. A proportioning valve helps without relying on springs/dampers entirely. I think Toyota was already worried enough about the general public's ability to drive mid-engined cars that they went very conservative with the bias.
In terms of Steve being right for the wrong reasons - care to elaborate? I'd love to hear your thoughts on that.
Yes, getting a bigger bite from the rear brakes will also get that weight transfer to the front quicker. I am still trying to figure out a way I like that is not complicated or expensive.
It's been so many years, it's hard to remember what my exact disagreements with Steve's theories were. I'd have to go back and reread all of it. I think it might have been his insistence on the slope of the roll axis being an inherently good thing I could not get him to explain. In my opinion, you adjust the roll center (if possible) along with spring, shock, and sway bar to get the desired roll stiffness and it does not necessarily matter where the roll centers are if the roll stiffnesses are correct. Maybe his emphasis on roll center location adjusted by ride height was because that became his main fine tune adjustment.
Certainly it's possible I misunderstood what he was trying to explain.
In reply to edmagoo :
(in reference to gaining more rear brake bias)
I believe the Club 4AG article suggested more aggressive (20% more so) than the front pads. I like this for a fun car in theory (I'm just bench racing here), but maybe not for the OP's daily driver. Seems an easy, relatively low impact way to experiment.
So any suggestions on brand and how to find pads with various levels of aggressiveness to experiment with this? Car came with new rotors and the supercharged brackets to space the calipers out for the larger rotors. It also came with new pads, but they are crappy no name brand pads. So run a good pad on the back and the cheap stuff on the front? Or is there a good brand where I can purchase something decent for the front and more aggressive for the back?
CAinCA
Reader
5/13/20 4:12 p.m.
I'd call Porterfield. They carry several brands and can tell you the characteristics of them all.
Hawk? We're well beyond my area of expertise (getting grinder dust/welding spatter in my ears/crotch).
edmagoo
New Reader
5/13/20 9:47 p.m.
The general consensus is that Toyota went way overboard with front bias on first gen MR2 brakes. However decreasing the front bias is moving towards the point when the rear brakes lock up first and the car spins even while driving in a dead straight line.
Different pad compounds front and rear is a good half-step but the generally accepted first full step for a first gen MR2 is to remove the proportioning valve. That is usually a bad thing to do but the MR2 is so far out of whack, it is still 'too much front bias' after removal. Nobody alive has reported that change locks the rear brakes first in the MR2. I believe that changing both the pads and the prop valve is favorably reviewed but I have not done it myself.
The correct thing to do would be to swap out the rear brakes for something much stronger and replace the proportioning valve with an adjustable proportioning valve. (dangerous if you get it wrong)
It is worth considering that even a vastly enlarged rear brake will only improve maximum deceleration by a small amount once the weight is transferred to the front wheels. It could negatively affect brake balance on downhill braking and trail braking. It should greatly improve the feel of the brake pedal though.
So no decision yet on the brakes, but plenty to do on the front and rear suspension. Pulled the rest of the front pieces out, cleaned up and painted all the front suspension pieces and the strut housings. The nut on both sides of the front control tension arms won't come off despite lots of penetrating oil, so I decided to replace them with the Techo Toy Tuning kit below that I found for a reasonable price. Just the red pieces in the picture, the blue control arms are not part of what I bought. These will be combined with my newly painted parts and reinstalled this week.
So I painted all the suspension pieces today out in the yard since it was nice, everything is ready to be reassembled.
I painted the strut housings in a yellow similar to the Koni inserts I am installing and then will use the Eibach springs I just traded for (thanks again lxnm). While I was in the front of the car, I pulled the radiator as I have a new replacement for it as well as painted the transmission and transmission shift brackets and linkage. Will pull the rear suspension tomorrow so I can get the rear struts apart so they can be cleaned and painted as well. Looks like I'll have to send back my rear Koni inserts and get the MK1B size as the struts are from the 89 Supercharged car. The previous owner must have installed the 89 rear suspension pieces, subframe and struts, but the top hats are from the 86 as they are only 3 bolt.
I also cleaned and sealed the gas tank yesterday. Painted it today so it is ready to be reinstalled in the car once the paint for the engine compartment is here and I can get it sprayed, so should be this week. I am supposed to have my wiring harness back from Wiregap on the 20th, so might have the 1MZ-FE installed by Memorial day along with my rebuilt front and rear suspension. This project is moving pretty fast!
In reply to Dusterbd13-michael :
I've found that I actually prefer spherical bearings like these for the shifter in my MR2. They still have a very solid,p feeling but are less prone to binding the shift cables. I'm sure you could achieve a similar result much cheaper with bits from McMaster Carr.
lxnm
New Reader
5/19/20 12:01 p.m.
Those struts are looking pretty good, I didn't go with yellow because Konis or Bilsteins. But, yellow seems like a good color for struts. And you painted the hubs too.
Let me know how the technotoy parts work out. My experience so far has been spotted, but I'm still eying their lower control arm bits. Apparently I'm a slow learner.
Thanks, pretty excited to get these all assembled and my front suspension should be done by the weekend. These look to be pretty nice and offer extended caster adjustment (3 degrees to 8 degrees). Looking forward to seeing if I really get "incredible steering feedback, zero caster deflection and EASY caster adjustment and alignment tuning." They look pretty solid, especially since the stock piece is basically a threaded rod with the flat section to bolt to the lower control arm.
Got my replacement koni inserts for the later 89 struts in the rear (larger diameter) from Tire Rack, so will be repeating the process in the rear next week. Should have some pretty front suspension pictures up soon.
lxnm
New Reader
5/20/20 7:09 a.m.
In reply to dherr (Forum Supporter) :
Are only the rear struts larger? On my 85, both front and rear strut housings are 45mm
Yes, the front struts are the same on any year, but the 87 and later rear struts are 48 mm
So today was assemble the front suspension day, everything has been painted, struts assembled and ready to go.
Finished result on the front, pretty happy with the result.
Rear suspension is ready to go, did not do it yet as it will be easier to install the engine with nothing in the way,so will put in all the pieces once the engine and transmission are installed. Brakes will be here this week.