Helmut the e21

retoropak

3 months later............

I had to redo the whole subframe. There was not enough room for decent size sump. Engine is mounted to the frame rails anyway so the middle section of the subframe was cut and pushed towards the front of the car. Don't mind crappy welds, once I hit it with some pretty epoxy paint it wont look that bad anymore. It seems that I can tig aluminum better than I mig steel.

Here is the oil pan that I hat to cut a little bit to sit flush with the subframe.

I also put together lower radiator mounts. It uses stock e36 plastic mounts that sit on steel brackets welded to the frame rails. There is enough room in front of the radiator to fit 3" intercooler.

I also got a new daily driver. I got rid of my xc70 and got F32. That b58 and zf 8spd combo is amazing.

YoungCR

Progress is progress! Happy to see updates on this. Congrats on the newer daily too.

retoropak

Since the engine sits upright the stock m42 manifold (e30) or ugly e36 one won't work anymore. Miata folks are adapting honda intakes with pretty good results. After some research I decided to get a Honda b series manifold and try to fuse it with m42 intake flange. Spacing is the same +/- 2-3 mm so it should line up fairly well.

It will get bosh DBW throttle body either in 68mm or ill go size up to 82mm if it fits.

Its a pro series so I expect some pro results . Sadly It will sit upside down so that beautiful logo wont be visible.

retoropak

I tried honda B series manifold and it sat too low. Then I tried volvo whiteblock without one cylinder and it was a bit off spacingwise and also sat too close to the firewall.

I figured its time for some custom manifold. I got some trumpets, plenum and a bit of a runner pipe. Flange is also on its way.

In the meantime I started wrapping up some other bits.

I welded shock mounts for the trailing arms. I started working on oil pickup and also threaded some holes for the windage tray. That cheapo oil pan came with windage tray mounts without any threads. Also internal oil pickup passage has a burr that obstructed 40-50% of the opening.

retoropak

I finished transmission mount.

Stock fuel tank wouldn't fit with e28 rear subframe so I had to trim it a little bit.

I started mocking up intake plenum to see if it will fit with a stock booster. The verdict is: I need boosterless brakes. I will try to fit floor mount Wilwood pedals and if it wont work I might go with firewall mounted ones. There is just not enough room for a booster even e90 one with vert mounted motor.

retoropak

I started putting together manifold. Just some mockups for now to figure out injector positions and angles.

I also got a set of wilwood floormounts that i am trying to fit. Looks like pedal position will be close to stock

retoropak

First part of the manifold is tacked up. injector angle could have been a bit shallower but I don't think it will have significant negative effects on performance.

retoropak

And intake is almost done. All tack welded and ready to be finished. I got some 1/4" plate to do the end cap and to add some reinforcemnt for vacuum fittings.

I will use bosh motorsports dbw throttle body. I am shooting for anything between 350-500whp. I think that 68mm throttle should do. The next size up is 82mm but I worry it will be too twitchy and drivability will suck.

Holesaw setup to cut 3" holes for trumpets

A little mockup with two runners to check the position of the plenum

All 4 runners in.

Fuel Rail

P_Roloff

Holy smokes, this is cool. That intake looks awesome, super excited to see that come to fruition. How is the throttle body going to be mounted, out the end of the manifold towards the front of the car or out of the side like an OEM one?

m42b32

This is awesome! A 350hp+ M42 is going to be a riot.

retoropak

P_Roloff said:

Holy smokes, this is cool. That intake looks awesome, super excited to see that come to fruition. How is the throttle body going to be mounted, out the end of the manifold towards the front of the car or out of the side like an OEM one?

Throttle will be in front of the manifold.

retoropak

I welded up the manifold. It was a pain. My 200amp tig had some trouble welding 1/4" plenum with the trumpets. Trumpets were quite thick with some sections close to 1/2" or more. I could use 50amps more.
I added fuel rail brackets and end cap. I also ordered bosch motorsports 68mm DBW throttle. I still need to get the weld-on flange for this throttle.

I ditched floor mounted pedals and get hanging pedal setup. I whipped new firewall plate and added the e36 column mount

YoungCR

Nice work on the firewall plate

retoropak

Pedal box is done.

I got my throttle body flange. I use 68mm Bosch motorsports TB. Its funny that you cant get that flange in the states. I had to order one from Sweden.

I ordered my eBay intercooler. 12x18x3" core. Should be plenty to support my power goals.

Next week will be finishing some bracketry and I should be ready to prep it for paint.

retoropak

I got my fleabay Intercooler it supposed to e 3" core. Well it is not. Its a 2.5" and has some shitty spoolgun welds.. I am not even mad I will just return it and get another cheapo intercooler hoping it will be a bit better. Anyone know ebay sellers/brands that might have decent 3" intercoolers? My 12x12 ebay intercooler that i got couple years back look much better with decent welds and nice looking 3" core.

I made upper radiator mount/ shroud/ intercooler mount.

Front frame rail brace might come handy. The e21 chassis flexes a lot. I will most likely use this brace as a mounting point for the skid plate

Strut tower brace will be next.

I also got my e90 gas pedal. It should work really well.

I started designing chassis electrical harness with my new fusebox. I got the inventory of all circuits including wire lenghts, colors, gauge and approximate splice locations.I will be ordering some tefzel wiring sometime next week.

I had a bit of an issue with clutch master fitting in the bay, So I had to expand the bay a little bit. Half a pound of seam sealer and some epoxy primer and it will look beautiful

retoropak

I got a monstercooler today. I think it is a bit too much @ 24x12x4" core. It fits though but I think I will swap it for something a bit smaller. It will take an hour for the turbo to fill this thing with air. I think transient response may suffer a bit. It might require some pie cutting to connect to throttle body.

retoropak

After couple of weeks of engine bay paint prep. I am ready to paint it. I build a beautiful spray booth in my garage with two box fans and shoot some epoxy primer followed by some seam sealer and more epoxy. Today i will finish it with single stage urethane in original safari beige.

I got the intercooler figured out. Wiring is next on the list.