How I Didn't Build a Lotus Indy Car from Scratch: PART II

Specific How's and Why's in the building of my poor man's Lotus 38 replica.

[@user-od9iz9cv1w]

Really cool car. So impressed that you did it yourself for $12k.

[@mikewoeppel6013]

This is a really inspiring video. Any chance you could go into a little more detail on the monocoque body construction and how you attached it to the front and rear subframe frames?

[@yoloboogie3674]

I too would like very much to see this

[@watsonwatson8051]

Loving these videos Ben, been watching the GT40 ones too. You obviously have learned great skills and you present them and your creations really well. Keep the details coming please! One of my favorites….

[@brianward6291]

This content is awesome. "Lessons Learned" are seriously the most helpful, discussion of pros/cons, etc. Thanks for putting in the time and upload!

[@geoffhurley8103]

Truly remarkable. You're the Allen Millyard of race cars. Subscribed and hoping to see more of this and the GT40. Thanks for sharing!!

[@shakeydavesr]

Very cool. Your son may be too young to realise it now, but his dad is a On the Down Low superhero,,, wait until he’s about 20- something and it’ll come to him. And he’ll forever kick himself for saying "why don’t you build a ? Lol. Good job, and keep it up.

[@joell439]

👍👍😎👍👍 - I will watch these episodes every time my motivation starts to decline as they are endlessly inspirational. Thanks for taking the time to give a snippet of the journey.

[@markloy9651]

Ok, you got me on this one. Gurney Eagle Mk1 it is. Wish me luck.

[@ceesklumper]

Great process and thanks for sharing. Yes the shrinker/stretcher can do unique and necessary things - easily. Smart to get some things done. Like I had some powdercoating done because it just didn't make sense for me to get all the tooling for just a couple complex parts I could not clean and spray paint myself.

[@FordHawke1]

Ben, just remember that modern car design and regulation specifies that feet are to be behind the centreline of the front axle. Its a good idea, if you want to keep your legs in a frontal collision.

[@benbeames]

Well aware and my feet are still 2.5 inches behind the center line with the pedals all the way depressed.

[@ablejohnson]

Excellent video. I am very pleased that the distributor is in the correct location. 😏

[@RAD-RC]

Awesome to watch all of these videos. Great to see how everything goes together, can't wait to build something once I have a garage!

[@bobquigley1957]

What an inspiration. Thanks for taking the time in making these two videos.

[@tjrizvi251]

Lookin good. Keep these videos coming

[@D3Sshooter]

love it

[@tinymotogarage]

Great to see how you did this build. Interested (if you want to do a load more YT content) in seeing more detail on all the different individual parts. Amazing project.

[@funkiwikid6106]

part 2. A great continuation. 7yrs of battle now is the ultimate test. Some Q's if you don't mind - Did you use steel or aluminum rivets ? Did you use adhesive in any of the joints ? Have you had any rivets work loose ? Any areas of the tub you've had to strengthen ? What did you end up with for front (lbs) vs rear (lbs) weight distribution ? My calcs thus far for my build to be, have highlighted your exact problem and for the same reason, I too wanted a longer wheelbase to fit longer drivers but found the weight disappearing off the front at a surprising rate. I want my battery behind the radiator where the Lotus oil tank was but I'm struggling for room while trying to avoid it being too long. The endless battle of trialaneering, thanks for sharing.

[@benbeames]

Avdel Aluminum rivets with steel mandrels. www.mcmaster.com/97517A045/ These rivets require as much force to put in as steal rivets. They're very different from aluminum rivets you find at the hardware store. I didn't use adhesive on this car. I had planned to (even though the original 38 didn't) but was afraid, being my first project, that I'd have to redo sections, and I didn't want to have to disassemble panels that had been glued. I have not had any rivets loosen nor had to strengthen any part of the tube beyond the initial design. Without me in it, the car is 468 lbs front, 926 rear. The distribution gets better when I get in it, but its still front grip limited. I desperately want to move the batteries to the nose and may make new upper arms that move the front wheels back another inch. Though I've only driven it a little bit since I made the upper arms that are on it now which moved the front wheels 2.5 inches back and it definitely drives better than it ever has. I may just slap some super soft autocross tires on it to cover a multitude of sins and call it good.

[@funkiwikid6106]

Thanks Ben. Again my same concern about adhesive in case of finding a problem, mods or crash repair. You've shown it's not needed so that's a huge help right there. Rules say I can't use sticky slicks so I need to get the balance as good as I can. You're at 34%F and 66%R which needs more front weight for sure. My calcs put me about the same and finding it hard to get it better while keeping the correct look. Every thing I do seems to add more rear weight, it's hard to keep the weight at the front. What wheelbase do you have now ? And what weights with you onboard ? Thanks again.@@benbeames

[@benbeames]

100 inch wheelbase. I don't remember the current weights with me in it. The last time I corner balanced it was a year ago. I happened to have a picture in my phone still from the weight without me but I didn't still have one of the scale with me in it.

[@funkiwikid6106]

I'm using 100" also. It's odd that I'm using 4cyl engine with less total weight, but the front/rear %'s come out the same and we're both fighting the same battle with that? The GT40 handles better, what's the front/rear weights on that ? Taking your battery from rear to front should help?, and it's easy to try with the car on the scales? Have you considered moving your rear wheels back the same way you did at the front? Big Q, I'm trying to make an Alfa transaxle work but having a huge issue with the low axle output? Don't want to lift the engine that much. How did you overcome that? What U joint/drive axle angles are you using?@@benbeames

[@benbeames]

My GT40 is 42/58 f/r. My 38 uses two batteries and there’s nowhere to put them in the front of the car that doesn’t cause other problems. Hence in years of thinking about, I haven’t done it. I’m not interested in moving the rear wheels back. I mainly autocross the car and it’s already a bit like driving a bus through the course. The front grip problem is a smaller problem than not being able to make the tight turns at any speed. Per the transaxle, my engine sits up a bit and is leaned forward so the transaxle sits higher than the front of the engine. With my engine, since I wasn’t going to pay for a dry sump setup, the engine sits a bit high anyway with the bottom of the pan perturbing through the bottom of the car about an inch. My half shaft angles (with cv joints) are extreme at ride height and also angle forward to the wheels. If you use road car stuff you’re going to have to face compromises. If you use race cars stuff you’ll make different compromises. But it sounds like you're fighting the good fight. Keep at it and good things will happen.

[@Александр-м1п8щ]

It looks great. Great job. I also dream of making a replica Lotus 25.

[@benbeames]

Go for it!

[@iguanamovies]

what a great project ! I love it. What I found rare is the rear spring/damper angle. In the current position, when the car rolls, the outside spring/damper work less and less because of the angle. Maybe it should be in a more straight position, I don't know how much, something like at 45º. Well, it's only what I saw, I'm sure you studied it while building.

[@amaer2971]

Amazing car! When you mention the monocoque, I am guessing you mean that if the entire (or nearly all) was aluminium instead of the steel tubing that the car would work find and still hold together. I am into the idea of aluminium as it is much lighter than steel but I feel uneasy with the idea of pressure created by the suspension and engine/transmission while the car is moving. Any good reading material on this topic?

[@benbeames]

Look up Len Terry’s book on chassis design. It’s on Amazon. Cars from this period almost always had stew bulk heads at 3 to 4 points along the car. Generally where the suspension attaches. They soon moved onto magnesium and aluminum bulkheads so it can be done but bare in mind race cars are only meant to last a year or two.

[@amaer2971]

Thank you! Turns out I actually have the book!

[@tjrizvi251]

Ordered! Found it for cheap cheap 😅

[@Robin_winzer]

Hi Ben, i love this car. What a type of steering gear do you use?

[@benbeames]

The rack is a stiletto rack (secure.chassisshop.com/partlist/19810/) then it connects to the front spindles with rod ends and aluminum threaded tubes. Then the shaft is just a hollow 3/4" steel tube running through two bearings (www.summitracing.com/parts/brg-700010) and then a welded on quick release hub (www.summitracing.com/parts/joe-13400) The steering wheel is a 10" wheel I got used off a Zink Formula Ford..

[@Robin_winzer]

@@benbeames Thank you, I have a similar project myself. But it gets as an engine for now a 1.8t from Audi. Later maybe a Twinturbo V6.