I am really interested in the way you have located your turbo next to the gearbox. So, would you mind my asking you some questions ?
How did you route the piping to the engine compartment ?
What thickness and diameter have you choosen for the exhaust piping ?
Have you tried to keep an equal length header ? Does it really matter ?
Thanks !
Gatron
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Mon Mar 12, 2012 3:23 pm
by Wally
Hi Gatron,
Routing: don't know what piping you mean exactly, but most pictures are there I think?
Here you can see where the exit boost pipe from the turbo is pointing to: almost straight towards the intercooler and it goes just under the firewall into the engine compartment: http://i174.photobucket.com/albums/w112 ... g002-1.jpg
Exhaust header is 38mm outer diameter (1-1/2" as the americans call it ), but its the only one I could easily find with slide tubing in stainless. 35mm would have been much better for 1200 cc and 35mm would also better fit the stock head exhaust port exit..
Yes, equal length IS better, but I could not make that in time for now. How much it makes a diference most nobody will be able to tell you, but read the JDM forums on high output headers and you'll start to see what the serious tuners do. Exhaust building is very time consuming and nobody makes a custom header in two versions just to test it out on the dyno and not change anything else.
I think keeping some length before the merge and NOT pairing 1-2 and 3-4 because its so convenient will help the most. Then, exact EL becomes less of a difference plus there is also something to be had in not making more bends then neccesary.
Just my perception on that subject, which is different then most on EL/non-EL I have noticed
BTW, I already seized up my main flywheel bearing after going over 5500 rpm for the first time
Engine is out and thinking how to get more oil into that d*amn first main bearing. I should have an old 40 horse bearing set with the oil grooves on the INSIDE like my type 4 has from the factory...
The normal for 'cross-drilled cranks' flywheel thrust bearing, even with my enhenced oil entry ports on the mains, just don't seem to cut it with the 21mm oil pump... I will change to 26mm, but still it could be better.
Maybe grooving the crank, but I'd rather have the right bearings with all the grooves on te right side.
Best regards,
Walter
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Mon Mar 12, 2012 6:49 pm
by mexico1978
Thanks for your answer
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Mon Apr 09, 2012 8:20 am
by Wally
That was from ~3500-6230 rpm.
I still encounter an uneven rpm signal which matches what my butt feels: it doesn't run right, feels like I have misfires, even though the vid sounds ok-ish...
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Tue Apr 10, 2012 12:43 am
by my_medusa
devils of the 1200cc challenge. nobody ever way problem free.
i had:
a bad 1. main bearing that ma body build in no 60 sec. of running the main was to small in case
a broken gearbox
a broken conrod
a lot of fun too
good luck walter hope we see each other on the 28.!!!
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Tue Apr 10, 2012 12:53 am
by Wally
Found the problem Chris: low compression on one cylinder and I know what the cause is: its a result still of the oil starvation issue I had before, which scored at least one cylinder wall bad enough to not seal properly anymore.
I WILL fix the issue and we will see each other at the 28th April!
Still, datalog showed 7 psi at 3500 rpm and 14 psi at 4200 though...
On a 1200cc engine with a WRX 2 ltr turbo, how's that!
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Tue Apr 10, 2012 2:21 am
by my_medusa
thats bad. engine out heads up...damn time that could be went into tuning.
but the numbers...wow.
had the same. my boost starts unter 1500 rpm in 3rd gear on my 1200cc with borg warner twin scroll from the mini cooper s.
14 psi at under 3500rpm.
when we think about the 85 hp 1200cc at 6500rpm we have VE about the 100% mark. those things can breath! every step down in dislacement is at the same a step up in VE and we use the same hads like on the 1600cc that very often have seen 100hp as NA on moderate rpm around the 6000RPM mark on portet original heads.
what i really wanne say!
i think you need a bigger turbo that early boost is just for street driven and not for big HP numbers
and find some good conrods
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Tue Apr 10, 2012 2:49 am
by Wally
my_medusa wrote:
i think you need a bigger turbo that early boost is just for street driven and not for big HP numbers
Now your talking!
Later spool also means less stress on the rods
I hope there will be a next year as that would make a uprated turbo possible...
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Tue Apr 10, 2012 3:13 am
by my_medusa
hehe thats right but more top end also is more stress on the rods more rpm too.
but you have done all you can do to the stock ones so let see how far you can go.
for next year i have two plans. hx30 or twin twin cooper s. every port has its own turbin entrance in harmony...sounds also cool
Re: 1200 Turbo EFI build 'Challenger motor'
Posted: Mon Apr 16, 2012 1:01 pm
by Wally
I like your thinking with regard to VE Chris! I totally agree too.
Finally got the engine running again after I had the cylinders honed as there was still some left-over damage from the oil starvation before. Nice even compression on all cylinders now