ForcedFirebird's m20 dyno thread.

[digger]

If you were able to program an alarm that was rpm dependant it might be useful

[e30davie]

On a rally car i was involved in we had a trailer stop light on the dash attached to signify low oil pressure.

[ForcedFirebird]

How valuable would an audible alarm be for oil pressure? Or is it too noisy to be heard in a racing environment?

If you were able to program an alarm that was rpm dependant it might be useful

On a rally car i was involved in we had a trailer stop light on the dash attached to signify low oil pressure.

We have a gauge in place of the stock dummy light. The car has been running without a baffle/scraper or light since 2013 on that car, but it has never been this quick (rule changes in the series with points/lap deductions vs modifications, better tires etc). Will be installing an oil light, and baffles/scrapers in the oil pan for the next event, needless to say. We were over 4 seconds faster per lap vs last visit to the same track, and a few of the same drivers.

[darvo]

Have you thought about using an Oil Accumulator and placing it on the rear of the car for weight distribution?

[ForcedFirebird]

Have you thought about using an Oil Accumulator and placing it on the rear of the car for weight distribution?

Installed several oil accumulator setups as well as diff/trans coolers over the years, but honestly, unless you are doing rigorous long races, they hold up well in e30's. The e36 platform seems to heat up diffs far more than engine oil (more tire grip, more power on the same sized diff carrier/ring set, heavier car). A very simple oil cooler and small e-fan or ducting goes a long way.


The current e36 sprint car sees oil temps matching, or lower than coolant temps, in the neighborhood of 169°f maximum. Took 2 1st place and one 2nd at the last FARA 300km event in homestead Miami two weeks ago.

[ForcedFirebird]

Apparently the stock crank damper does not like 8000 RPM.

[ForcedFirebird]

Have you thought about using an Oil Accumulator and placing it on the rear of the car for weight distribution?

After reading this back, had another thought. Accumulators add points to our car in the series. We are at 495 of 500 points allowed, so no room for much of anything (want to say accumulators are 50 points or so, the e30 is already a 450 point car).

We ran one of the 180whp cars last weekend for a 14hr race at Sebring. We were running 8th of 72 cars and got a black meatball flag for a broken tail lamp, but was kind of a good thing (3hr to go for checkered flag, so it was about 8pm and dark). The driver mentioned he had no brakes, the front pads were metal on metal. Couldn't get the rear running light fixed, so removed the tail light backing plastic and stuck a flashlight in the housing (still had third brake and drivers brake lights operational, minimum 2 is legal). 23min pit stop dang it. Finished the race in 17th - only 2 BMW's completed more laps than us (both e46's) and the closest e30 to us finished 37th - which is an m50 swapped car in the unlimited class. Not bad for the little m20 that could. :)

[digger]

Apparently the stock crank damper does not like 8000 RPM.

what engine was that from?
All the other rubber bits degrade with heat, time and stress so this is no different. i bought a new damper for this reason.
i was in discussion with ATI to but not looking promising as the water pump and alternator drive is in the way so you cant get enough thickness

[LowR3V'in]

still it did great for 30 years. my stock nissan blew up at only 20.

[ForcedFirebird]

what engine was that from?
All the other rubber bits degrade with heat, time and stress so this is no different. i bought a new damper for this reason.
i was in discussion with ATI to but not looking promising as the water pump and alternator drive is in the way so you cant get enough thickness

New dampeners are NLA. We have been searching for a week. This is the SCCA National champ, 208whp/184wtq b25 12.5:1compression and our head work. Hoosier came out with a new stickier compound and it was a testing day. Crested a hill at the top of 3rd and was 500rpm more than usual due to exit speed. Tapped 8000rpm and BOOM! This motor has been running for 2yr, nly was able to squeeze 2nd place last year. (1" porting rule mentioned earlier in the thread, stock sized valves).

Only options ATM are using a 24v damper, which is larger in diameter and has the OlT mark at 2 o'clock vs 10 o'clock (easy fix), will require custom CPS bracket and either change to vee belt damper, or serpentine alternator other oprtion is totally a custom /adapted unit.

Metric Mechanic has been producing 7700pm engine for a minute, might call Jim as see what his thoughts are, but right now need to get the car back on the track.

Just for giggles, let's listen to the music of my peoples!

https://www.youtube.com/watch?v=WdgIqhFOw80

[2mAn]

Metric Mechanic has been producing 7700pm engine for a minute, might call Jim as see what his thoughts are, but right now need to get the car back on the track.

If you call Metric, you will need more than a minute, Id set aside an hour or two lol

[digger]

Years ago MM used to produce a light weight version of the vibration damper. they no longer do this, i wonder if they encountered issues doing that as it goes against modern thinking

[digger]

Apparently the stock crank damper does not like 8000 RPM.

any chance you could cut it up and measure the rubber bits and steel so i can model in CAD and do some calculations? you could always send it to me

[ForcedFirebird]

any chance you could cut it up and measure the rubber bits and steel so i can model in CAD and do some calculations? you could always send it to me

Not likely as he is about 1300 miles away, but can ask.

[digger]

i just want to see which part is rubber and some basic dimensions will probably do if it is cut up a bit

i think i have a solution for the ATI option for the M20 that retains all the pulleys locations with little more than some modified front covers. there are a couple of options i came up with based on ATI's initial work to fit their recommended Inertia ring.
- one option allows the stock OE crank gear (albeit the new version) and 24V 95mm long centre bolt used for a typical stroker which is ideal. will be discussing with them in coming weeks.
- another options a new gear that integrates to the damper but means the big M18 bolt needs to be removed to change the timing belt which is not ideal. this will add a fair bit of cost to the already expensive price so fingers crossed the first option can be taken from concept design to a detail design.