Turbo Tercel 4WD

[SynthDesign]

Lookin good. I can't wait to see how it turns out. A little warning, the stock clutch is only rated to 85ftlbs of torque. I've got a built 3AC and on hard shifts, I can slip the clutch on occasion. A built 4AC with a weber can smoke em' pretty quick too. I'd recommend stepping up to a higher rated disc and pressure plate. It sucks having to pull the trans out for a fried clutch after 500 miles. Also very curious if a DGEV Weber will work with a turbo setup. I know they don't work very well with a supercharger.
Keep us posted and take lots of Pics. Also happy, like many others, to welcome you to the forum.

[shogun]

ive done the turbo thing once before, but i went drawthrough, i would run the biggest turbo you could spool decently, would try a t25 or a td04 from a volvo, meth injection would be nice but to be adequate for daily use you would need a biiiig tank.

try a vw intercooler or a dsm one, even better a saab one, that fits in place of the ac condenser

good luck on your project

[k750h]

Okay guys... I know it's been a while since I've posted anything here; but I've been super busy with work etc, got discouraged with the project, and just haven't had time to respond or do much else with the Turbo Tercel.
After posting about the strut and rotor swap I did get ambitious and swapped the turbo motor in the next day (Saturday) and got it running. I sure wish I'd have taken some video that day because without a compressor inlet, or any exhaust; it sounded absolutely awesome! The next day I completed welding up the carb hat/comp discharge plumbing, installed the exhaust and started playing with electric fuel pumps to get the system working right. With no extra fuel pump, to no surprise, the car wouldn't run quite right... as soon as the turbo started making boost it would of course push the fuel out of the bowl and it'd fall on its face. With one of the 5-7 psi pumps installed, the car would start to pull really nice, but under continued boosted load it would start to act up again... addition of another 5-7 psi pump all in series with the stock pump does the trick (kinda). With both pumps running the car pulls like crazy and works well except when coming off boost and back to idle... With this much fuel pressure, it's just too much for the needle valve and it wants to flood out; however it works fine so long as I keep the RPM's up at "idle"
Never the less, I did say something got me discouraged: bottom end bearing noise in the motor! I rebuilt this motor several years ago and had a bit over 100,000 miles on it since then. This motor never gave me any trouble at all, so I never even bothered pulling the main or rod caps... lesson learned I guess. Either way, I drove the car all that week trying to get it dialed in with the addition of a rising-rate regulator which fixed the flooding condition, and taking the stock pump out of series. The system seems to work great but the bearing noise is not good. Cruising in the car now in 5th gear, I can build 5 psi boost pressure at ~2,500 RPM while having about 7 psi of exhaust manifold pressure at the higher engine speeds... With boost coming in this soon, it feels like it makes about twice the torque that it used to which is really nice, but I think I'm going to put a larger turbine housing on the turbo and see how it responds to that (get the boost to come in a bit later). I can't detect any detonation at any point of load/speed... I've been running premium too which I'm sure helps, but overall this is good news. With exception to the obvious discouragement of the bearing noise, I'm very happy with how it all works now The car pulls really hard through 3rd gear and 1st is almost useless now... especially in the rain; in the wet, 1st is useless, 2nd gear will light the tires off immediately when boost comes on, and in any sort of curve in 3rd gear, it'll spin the tire(s) when running hard and on full boost. Again, this is when the road is wet, but us all knowing how these cars run normally... this is showing a pretty significant bump in power When the roads are dry and in 2nd gear, as boost comes up and the car is pulling nice, you can hear the tires breaking traction... I don't leave a big trail of tire marks, but they're definitely not getting traction which is exciting for someone who's driven one of these cars in one form or another for the last 10+ years!
I've got some work to do now for sure with having another crank ground (I have a few) to clean up and a new set of bearings... I'm hopeful that the problem isn't due to simply the extra power and that the bearings were maybe hurt already and I've just accelerated the process? I'm really reaching here of course, but it just doesn't make much sense to me why the bottom end is suddenly hurt. Either way, I've come to far to give up now so I'll do the work and give it another shot with a fresh bottom end. Maybe when I get the engine apart, I'll find something simple, but if not I'll have some head scratching to do before I'm comfortable. I don't know for sure when I'll get started on this again, but I just thought I'd let everyone know where I'm at right now.
-Till next time...

[Petros]

Sounds kind of fun. I would think you would want the power in the lower rpm range if you are looking for more torque.

I have a few suggestions: with all that extra low end power you do not have full oil pressure when you are loading up the bearings. So when you get the new crank and bearings in I suggest a couple of mods to help the bearings. Get a new oil pump and take it apart, radius all the internal edges in the outlet and in let. shim or stretch the spring to allow more oil pressure. radius (very carefully) the oil outlets on the crank journals. You might want to chase the oil passages with a sharp drill to clean the inside of the boar. Also, pull out the plugs in the block for the oil passages and run some stiff bore brushes in and out of all of them to make sure they are clear. Clean up any burrs or roughness you can see in the oil galleys and bores if possible.

This will help you deliver more oil flow and more oil pressure to the bearings. Also, you might want to switch to a diesel rated oil rather than the normal motor oil, and/or try some of the high pressure additives to improve lubrication.

Make sure the bearing clearances are at the tight end of the tolerance range. That should solve any bearing problems.

Good luck

[shogun]

nice to hear the car is runing, idealy you should have 3 psi over boost pressure, you should get a rising rate regulator and get 5-6 psi base, set your timing at 8° if you get too much timing up top use stiffer springs in the advance

and get your emulsion tubes tuned for boost it is what gets the best results

ps. bpr7 spark plugs