'85 Quantum 1.6 TD FWD sedan; which way to go?

[TDForNow]

WOW! It took a few years to find a site like yours... awesome!
 Well it's getting hard to start this winter w/o the block heater. Compression is weak, when turned by hand 3 cyl's feel like a strong gasser and # 1 feels like a weak gasser! What else to expect after 468k miles of hard driving (used to run triple-digit with a malf'd wastegate on the 1st head) :oops:  
 When I replaced the head (a rebuilt w/ rebuilt inj's) 2 yrs and 55k miles ago, I put new rings, big-end bearings and oil pump. Cylinder bores were a little out of spec then but the tight budget won-out. I'm sure they're well out of spec now!
 I'll have to do something soon and when I do, I definitely want it to be able to stomp on the gassers, :wink:   but what options are availiable for IDI's? It's got the stock Garrett turbo and no intercooler. Obviously, I'll need more flow, fuel and a cooler/bigger boost. Or do I look into a TDI transplant either with a mech pump or with the full electronics (PD130 with all the goodies!!! :twisted: ). Body (minus the crappy paint cond) is sound and interior is great, but will the 4-banger 5-spd trans handle the bigger stress and is a Quantum worth the trouble? I like that it still handles pretty darned good despite its age.

[TDForNow]

So.. What are my options, any suggestions on which way would have more results as far as bang for the buck?

[steve]

My Q has similar miles.  I rebuilt the engine about 50K ago but did all of it.  I had a broken ring that ovalized a cyl so I had to bore it over .040.  Now I have a new Topline head on there and it runs great.  It even ran great in the winter at 8500 feet where I used to work, with no block heater.

I've adjusted my IP and found that it makes plenty of power for me.  There's more you could do.  If you hang out at this forum long enough you will get far more ideas than you can handle.  intercooler, turbo boost, cam and IP timing mods, just to name a few.  I guess it depends on your goals and budget.

[TDForNow]

I've been leaning toward a TDI transplant fueled by a enhanced mechanical IP. But what head mod's can be done to a TDI? What mod's will the pistons accept? What will the bottom end handle? Speaking of an "enhanched" IP, what can be done to a mech IP? Has anyone found a solution to get more than the stock 2.5 deg cold-start adv without screwing up the basic timing to help with lowered compression? I'd like to use a VG version of my T-3 or equivalent. The stock TDI turbos look really small for any heavy breathing. Why are some folks using mod'd gasser intakes? I thought turbocharging made runner tuning moot. In that case, I've got an A2 1.8/8v intake that would point the connection fwd in my Quantum toward any proposed FMIC. From what I've seen so far there's quite a bit that's possible with the IDI TD's.  Finally, what are my options for clutching and the capabilities of the 4 banger 5 spd in my car? Can a 5spd tranny from a 5 cyl Q/4k/5k be swapped-in? Thanks in advance!
Alain

[TDForNow]

I've sent the following e-mail to Giles. What does anyone else think? Sound like a good road to drive down?

Hi Giles,
   Thanks for getting back to me so soon. I'm still on the fence on which way I'm going to go. I currently have a tired 1.6 IDI TD in an '85 Quantum sedan. I want good drivability  with  good torque down to 2000-2500 rpm and to really pull hard above 3000. Mainly for road use. I'm researching wheather to rebuild it having to go with new pistons at least .020 over with head mild porting, dropping compression to either 18 or 18.5:1 by milling in the combustion "chamber" of the piston domes and/or the prechamber, FMIC, VG version of my garrett T-3 or similar,  better (from what I read so far) intake and 2.5" exhaust. Or use an early TDI with the same mod's (hopefully w/o the over-bore) fueled with a mech IP. Can a VE pump handle this on a TDI? I expect (with some work) it would on an IDI TD. I've read where some (ie: RabbitGTDguy) are considering a pump from a Cummins 4bt for their mod'd TDI.
    Back to the advancing cam, what can be done to get more idle advance to offset the lowered compression when cold starting?
      Thanks again.
      Alain

[TDForNow]

I Gotta a Head question... I think it's most likely junk, but my old head has "splits" between the valves (livable I'm told) and cracks in #'s 2 and 3 c-chambers between the intake valves and the pre-chambers (#2 has material actually lifting out of the crack), one of them is into the water-jacket. I was told that this is actually repairable. I think it's nothing more than an industrial sized paper weight now! Any confirmation?

[steve]

My vote is for a new head.  I've just had no good luck with any of the 5 rebuilt heads I've gotten over the past 10 years  :shock: ... assuming that yours can be rebuilt.  I'm not sure if it can or not.  But it would make me real nervous, expecially if you are wanting to mod some stuff for more power.

[TDForNow]

Thanks Steve, that's what I was figuring.

[TDForNow]

bump............BTW, how much Audi 4K stuff is compatible? I guess I could use the bad head to practice porting experiments.

[steve]

my seats are from an 84 audi 4000 (FAR better side support than the original seats)... and that's all I know as far as compatibility.

[moosiah]

engine stuff is mostly the same,  other stuff...... my frankenbunny wears  a4000 rear brakes ,front rotors w S2 front calipers and a4000 gt 14x6 rolla rims...    thank you VW for the Mr PotatoHead parts interchangeability!!!!!
VW..... :twisted: .......  pimped out in Germany!!!! :lol:  

[TDForNow]

That's good to hear, parts for the Quantum are getting hard to find. I'm finding more 4K parts are still avaliable, especially performance parts.