Wayne H.
'91 Dodge Spirit ES 2.5L turbo 5spd
'05 PT GT 2.4T HO autostick (RIP)
'89 Plymouth Acclaim 2.5L turbo auto, "Slugmobile" yes, THE Slugmobile!
'89 Dodge Caravan SE 2.5L turbo auto, "Mean Mini" yes, Gus' Mean Mini! (Current best 11.699 @ 114.43 mph! - Oct 15th, 2022 Cecil County Dragway, MD)
MeanMini dragracing videos: https://www.youtube.com/playlist?lis...URZLB1RxGYF6vw
and other cars, trucks and motorcycles
https://www.youtube.com/user/SlugmobileMeanMini
Well it's been a busy fall/winter. In October I sold my house and neglected to buy a new one so everything went into storage. I was expecting to get a bunch of machining done but a project I had promised someone else has been taking way longer than expected partly due to not having a garage to work in anymore. So what's left when everything is in storage and you have no garage? Time to make some animations and 3D printed prototypes.
First off is an animation and prototype of the quickspool valve. I didn't like the what was available on the market as seen in the third picture. The butterfly creates a blockage on the second scroll, when closed the exhaust runs into a flat 90deg wall, and you lose all the advantages of a twin scroll header/turbo combo. Instead I designed a collector to house the flapper. This way there is no blockage when opened, when close there is an angled wall to help direct the exhaust and when opened the flapper becomes the division to retain all twin scroll advantages. The prototype turned out good and I'm excited to try out the real thing.
Secondly I thought I'd make an animation of the suspension system........just because it was fun.
Impressive, as always.
In your calculations, how much spring rate would you need for each of those? Follow up question, to avoid having to source out 1500lb springs, do you just change the length of the moment arm thingies (not sure what that component is actually called)? Great idea on the DJ valve Might as well put your name on it right?
AJ (no More Alan) 84 Rampage RT TIII/568 Quaife 87 GLHS dealer optioned Red 16V Masi/568/Quaife
90 Masi 16V White/Ginger/Black
89 TC Masi 16V Red/Ginger/Black
86 GLHS #110 RoadRace Built 89 CSX-VNT Recaro Car
89 Turbo Mini 'Woody' 85 GLHT 'RedBox'
2014 Explorer DD'r 3.5Twin Turbo Ecoboost AWD and 500HP
My profile page has over 20,000 views, I'm somebody LOL
AJ, it depends on the rocker arm ratio (just like the valve train!). I can't tell and I don't remember, but it looks very close to 1:1...maybe 1.5:1, so it won't be that much. If he were to delve into aero, then this gets tricky.
Like Reaper said the rocker (moment arm thingy)/motion ratio is what drives the spring rate needed to get the desired wheel rate. The motion ratio is how far the wheel travels vertically vs. how much the damper compresses/extends. So if the damper only compresses 1/2" for every 1" of wheel travel then the motion ratio is 0.5. 3/4" to 1" = 0.75, 1" to 1" = 1.....you get the idea. The Wheel Rate = Spring Rate * MR^2 or inversely the Spring Rate = Wheel Rate/MR^2 when using a desired wheel rate. So the lower the motion ratio the larger the spring needed for a given wheel rate. A smaller MR means less damper travel and allows a more compact setup but the spring rate grows exponentially and also puts more load into the chassis.
After much reading I decided to start with a wheel rate of 90% of the corner weight. My corner weights are all guesses at the moment but I will probably start in the range of 550lb/in up front and 450lb/in in the rear with a MR of 1 on all 4 corners. The nice part of the pushrod/rocker system is you can fine tune the wheel rate without being limited by the available spring rates by adjusting the MR through rocker geometry.........if you have the $$$ to make more rockers and the skills to tell the difference. I'm fairly certain that's not me.