retoropak
-
Posts
103 -
Joined
-
Last visited
-
Days Won
6
Content Type
Profiles
Forums
Events
Gallery
Store
Posts posted by retoropak
-
-
-
-
Olds Toronado
Sent from my iPhone using Tapatalk -
Was this your issue?
Yup exactly.
Sent from my iPhone using Tapatalk -
How about milling 1.5mm from the piston? They are claiming the got some extra meat to allow for valve pockets
https://aapistons.com/collections/piston-liner-kits-sets/products/vw-92mm-2180cc-racing-forged-piston-kit
Sent from my iPhone using Tapatalk -
What boost? Lets assume i am building NA 100hp 2.1 liter m10 for now.
Lets get back to the question.
A. Deck the block to achieve zero deck
B. Mill the pistons to get the zero deck
C. Let the pistons poke out the block and use thicker HG
Also the reason for the vw type 1 pistons is that they are cheap.
$350-420 for a set of four forged mahles or JEs is really attractive when you compare it to a 800-1000 for a set of custom ones
Sent from my iPhone using Tapatalk
-
I will never boost another engine with stock pistons. With very old used pistons you start off right away at a disadvantage being that the ringlands have been cycled and are closer to fatigue failure than new (as you know, aluminum doesn’t have an endurance limit)
Get some forged pistons and you can specify all the parameters you want to.
Thats the plan to get the vw type 1 forged JEs or Mahles.
Sent from my iPhone using Tapatalk -
I am planning to build my m10 this summer. I will be shooting for 400whp on e85
I have two options.
Option 1 using 92x82 vw type 1 pistons and s14 rods
Bore:92mm
Stroke:80mm
S14 Rods: 144mm
Deck height:217.5mm
Compression height:35mm
Headgasket thickness:1.5 or 1.8mm
Combustion chamber volume:63 cc
Compression ratio: 9.25:1
With this setup pistons will be sticking put approximately 1.5mm out of hole. With the 1.8mm gasket i should have 0.3mm clarance.
Or I could mill 1.5mm from top of the piston and zero deck it which will result in compression 8.25:1 ratio
Option 2 using 92x69 vw type 1 pistons and m10 rods
Bore:92mm
Stroke:80mm
M10 Rods: 135mm
Deck height:217.5mm- 2.7mm= 214.8
Compression height:39.8mm
Headgasket thickness:1.5 or 1.8mm
Combustion chamber volume:63 cc
Compression ratio: 8.25:1
I would have to deck the block 2.5-2.7mm to get it "zero decked"
What would you rather do? Deck the block and use shorter rods or mill the pistons and use longer rods?
Or maybe let the pistons stick out the holes and use 1.8mm gasket but it will give me only 0.3mm clearance.
Thanks
Sent from my iPhone using Tapatalk
-
I am a mechanical engineer and work with a couple dozen of other engineers ranging from mechanical and civil thru structural to signal and electrical. I have not found a person at my firm that i can talk to about cars. Its all black magic to them.
Its all about passion. You love something, you commit yourself to it and become an expert. I guess there is no love for cars where i work.
Some people do not want to know how stuff works. They are happy as long as the product meet their expectation.
I personally spend weeks researching before i select the parts for my builds to the point that i have most of the parts including critical dimensions and sometimes part numbers memorized.
For me it was simple: Read and learn and make educated choices or let somebody else decide for you or translate the car-nerd'ish to you so you can decide.
The bottom line is that things get lost in the translation and if you do not know what you need you better have somebody you can trust to guide you thru the process.
Sent from my iPhone using Tapatalk -
-
This might seem like a dumb question at this point, but why cant you use the factory sensor in the rear diff?
Original speedo is cable driven. He would have to swap e28/e30speedo which i believe are different diameter.
I have the same issue i will most likely save some money and use the stack dash and get rid of other gauges.
Sent from my iPhone using Tapatalk
-
I will be fabbing up some exhaust today. I have my 3" downpipe and vibrant resonator welded up but it terminates right behind the driver seat. I already tacked under the axle portion. There is not much clearance between driveshaft and body right before the rear subframe. I will need to oval that 3" to keep the clearance. I should be done today. Will shoot some pictures later.
Sent from my iPhone using Tapatalk
-
Note that with e28 subframe you will have 25mm wider track per side. So your standard e21 offset ( et13) might be a bit too much.
Sent from my iPhone using Tapatalk
-
E21 vs. e28
Jig the e21 subframe locking the centers of the mounts and centers of the output and input flanges. Alternatively measure the crap out of it.
Chop.
Measure.
Tack weld. Test fit. Make corrections and weld.
Also, you will. Need to relocate the diff mount bracket and center bearing and shorten the driveshaft.
Sent from my iPhone using Tapatalk
-
Thank you all.
Here are couple more.
5lug swap
E28 rear subframe and e12 front hubs.
Once i got the safari running i will finish front e28 suspension swap with some spherical bearing goodies
Ford edis trigger wheel and sensor for the safari.
Ls coil brackets
Actually i am thinking about swapping 2.3 8v volvo red block into the blue one. [emoji851]
Sent from my iPhone using Tapatalk
-
Hello my name is Wojtek ( voytec do not mistake with vtec)
I registered a while ago but never introduced myself.
I live in NW burbs of Chicago.
I cought bmw bug when i got my e36m four years ago.
It was an awesome car. But i found it too new. I wanted something simpler and e21 fit that perfectly.
So i found rust free 1983 in detroit with all records all the way back to 1983 including receipt for 600 mile inspection.
In the meantime i aquired 2 other e21s and started swapping m5x to one of em.
Sometime at the beginning of the year it figured that it is going to take me 3 years to get the blue e21 the way i want so i put that project on hold and decided to turbo the safari beige.
Last weekend i resprayed the engine bay and i can start assembling it back.
Safari will be sporting stock m10 with arp head studs, BW s252sxe, ms2x, tilton twin disk clutch and small case lsd for now. Planning for 10-12 psi for now until something explodes. The plan is to have it running by the end of the month.
Long term goal is to build the bottom end and beef up the valvetrain and shoot for 400 on e85.
Sent from my iPhone using Tapatalk
-
Stroke m52 to 3.0 with the m54 rotating assembly. That way you can refresh the m52 with new bearings and gaskets and still be cheaper than s52.
It just happened that i have m52 i that don't need[emoji39]
Or m50nv stroked to 3.0 with m54 bits and run crazy cam and itbs. Oh i just realized that i have n50nv too that i might get rid off [emoji848][emoji6]
Sent from my iPhone using Tapatalk
Timing vs. boost
in General Technical
Posted
I checked timing on my m10 turbo again yesterday and it seems that i had a tiny 20 degree mistake.
tooth#1 angle on the ms2x was set to 80 degrees and the actual sensor position was at 100degrees BTDC
The 200kpa top row on my ignition map was set between 15 degrees@ 2300rpm, 13 degrees @ 3.5k and 18 degrees @7krpm
Boost comes in at around 4.5k on 3rd and about 300rpm lower on 4th and even lower on 5th (i have 3.91 rear end)
Compression is around 8.5-8.8:1 running 93 octane
Now with my small mistake it was more like 33-34 degrees @ 12psi @ 4-5k rpm.
There is no noticable knock.
How the hell the engine survived that much timing? I know that late spool and that 3.91 is helping but is it enough to keep it from kncoking?
I did maybe 1500 mile like this and its still holding up.
How much timing is too much? What are you guys running on your m5x and m20 turbo setups?
Thanks