boxerfan

I gave him to a friend who was in desperate need. FrankenAudi left for his new digs yesterday. So long Franky ol' boy.

So... Now I have some things to think about...

I have the... ahem...'spare' V8 here... I have a nearly complete MC1 rebuilt with MC2 cam and 40mm valves. I have a soon-to-be-arriving 1991 200 20VT Motronic ECU. And I have a V8 that has alost everything I need to EFI the MC1 with. Hmmmmmmmm....

That being said... I am driving a 1990 V8 as well... and I happen to have accumulated a pair of RS2 turbos... and the 1990 V8 ECU and the 1991 20VT ECU are nearly identical... Of course they aren't plug and play since the code for the 20VT will need to be adapted for the V8 configuration. I wonder what 0.8 bar of boost would do on a V8?

I'd like to hear everyone's musings on these ideas... The I5 into V8 project is substantially easier... And looking at the numbers that are coming out of tt V8 projects I question the extra effort required... however the torque must be just silly with a tt V8... What to do, what to do...

20VT90q

think that they are similar. They are both made by Bosch and maybe look similar, but that's where it ends. Reprogram, how are you going to do that? Just Megasquirt it.

mcorrow

Boxer: What's a "tt V8"? (stupid question, I know)

icon73

twin turbo conversion, few project cars on MG forum have this done.

itsav8

As 20VT90q says the ECM's between the 2(200 20vt 5spd! VS 90 V8 AUTO) are no way close to being even remotley the same! Not to mention that the motronic has controll over the injectors(which there are 5 VS 8!) But why are we talking about this cause you'd need standalone in eather event.

& 6PSI to low 10PSI is ideal for a TTV8 conversion. RS2 turbos will blow up the motor...some small Ko's will do the job.

An I5 into a V8 isn't easy by any strech...cause why would you want to do that??? Not to mention if you think that a 5spd tranny will just plop into a AUTOMATIC tranny tunnel I'll start to laugh now...
Not to mention that the turbo trannys aren't the same gearing as the V8's. 3:89 VS 4:11...but again the key to any of these is standalone!!!

OH, & an early V8 tranny wouldn't hold up for long under 8PSI!!
Thanx
Ron
90 80q 20vt AAN? stroker! project
90 v8q 3.6 not stock
93 v8q 4.2 "The Green Monster"
& a porsche 944 F.S(somethings gotta go!)

mcorrow

AHHHHH! I thought it referred to the Audi TT... (and couldn't figure out why)...Thanks!

boxerfan

The harness is nearly identical. One chip for fuel and the other for spark. One uses a MAF and the other a MAP. I'll make it work by cross referencing the code from one to another. I also have a Porsche 928 S4 chip I was given. I hope to be able to pull out the locations for the timing and fuel maps. After that I hope to be able to jig the code in the 20VT unit to operate on the V8. Personally, I'd like to try and work it out for fun. Shouldn't be too hard... I just need a little time on it.

boxerfan

According to the schematic for the V8 the fuel injectors are triggered off the same lines as the I5 but one less. It looks like the fuel injectors are set up to fire on each revolution of the V8. The injectors for the V8 are fired in pairs and hence are provided a ground each time the motor completes one spin as opposed to a direct injection measured to fire once only on each turn.

Have either of you guys torn apart the code for these ECUs?

Triggering spark is the same sort of thing. Again, as is blatantly obvious, the V8 must look at 8 sparks whereas the I5 only 5... yea... no biggie.

I have a scrapped Avant here that is going to donate the tranny tunnel and pedal assembly for a 5 speed conversion. There is a 4kq around the corner that may donate the transmission so the gearing issue is resolved as well. Or... the 200 rear end may go in... dunno yet. Still weighing it all up.

RS2's will only blow up the motor if there is no control over the boost. I am thinking that I'll start by operating with stock 5k WG springs and hence limit boost to a couple of PSI. The stock V8 internals should handle that all day long. I was originally thinking of using k03's but I happen to have the RS2s here. The built-in WGs would be convinient.

The 'spare' V8 will be stripped and rebuilt. I plan to mill the pistons slightly to reduce compression and use some ARP head studs for a superior hold on the heads. I'll then be looking to either regrind the cams or adapt some other cams for my purposes.

Anyway... I'm glad I could provide you with some ammusement. Still think it is impossible?

It might be easier to go with MS or 034, but there is definitely some experimentation that goes along with that as well. If I were to go that route I think I may go MoTec. I want to have a crack at this first just for kicks.

fastSLAB

is not the v8 made up from two VW I4's?.. i thought they were the GTI flavor, couldnt you disect some parts that way? i cant remember if the GTI was turbo for the yrs that the V8Q was produced, but if it was .......

boxerfan

Yea... That's stuff I'm trying to investigate. I'm not hopeful that the 1.8 cam will swap over because of the distributor drives but can't discount it yet. The pistons are another possibility as long as the wrist pins are the same size and location. I hope to find one at the wrecker and rip it apart to have a good look. I think I remember reading that the con rods are the same so there may be hope there.

Also... the V8 intake is just horrible. That thing must be 30 feet long by the time gets to a cylinder! I'm wondering if a pair of 1.8T intake manifolds could be used or even welded together to make a good plenum. With the TB's linked this could be pretty cool. Run them in opposite directions and the plumbing could look really cool. I'm thinking that a pair of Subaru hood scoops for ramming air through twin intercoolers would look pretty nasty. A pair of truck cowl vents might work about as well and look less obtrusive.