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yupididit
yupididit UberDork
4/29/20 10:03 a.m.

In reply to de80q :

I think I'd prefer a 20VT if I was to go that route. A none turbo 20V would be interesting too. 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/29/20 10:07 a.m.
de80q said:

I should also probably mention that I hit 22psi at about 2700rpm.  That is with a minorly cracked exhaust manifold.  Unfortunately the manidolds on these are known for cracking.  I have repaired mine once before, which is why I'm having to build another.

He'll need to build a new exhaust manifold to fit it in the engine bay, but you can also convert a 10V to a 20V with a few parts (aside from the head).

 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/29/20 10:09 a.m.

Here's my buddy's 924 Turbo running a 20VT in Endurance racing:

 

They keep the boost levels relatively low to save fuel and drivetrain wear.

de80q
de80q Reader
4/29/20 10:49 a.m.

In reply to Stefan (Forum Supporter) :

A 10v NA motor can be built with a 20v head yes.  You have to be especially careful when tuning it though, unless you go the custom piston route.  The ghetto 20vt can make descent power  though.  If you put a 20v head on a 10vt engine the compression will be extremely low as with the 10v head I'm running around 7.8/1 with my MC1 if I'm remembering correctly.  Oh, you would also need to machine the block for oil squirters.

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/29/20 11:24 a.m.

In reply to de80q :

Oil squirters aren't required, but they are a good idea if you're that deep into the engine.  A low comp engine with a properly sized turbo would likely be just fine in a lightweight 924.

Basically considering how thin 20V engines are on the ground, my plan was to build one from whatever I5 block you could acquire (a 2.5 diesel could be fun).  So pistons, crank, rods, heads, etc could be picked up from Motorgeek, Carpart, eBay, etc. it may end up more expensive, but you end up where you want in trade for sweat equity and a bit more time.

 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/29/20 11:26 a.m.

More pixxors of their 20Vt swap:

The Audi TT bellhousing spacer on a 924 Turbo bellhousing.  They welded them together for strength.

Ditched the 924 Turbo's 911 style pulltype clutch for a bellhousing mounted throwout slave setup:

Log turbo manifold with some additions to relocate the turbo/wastegate around the strut towers:

Built oil pan to clear the crossmember/steering rack:

They modified the crossmember like the 924 GTR and 944 GTP to make it easier/faster to swap the engines out:

docwyte
docwyte UberDork
4/29/20 5:37 p.m.

In reply to yupididit :

No, the lag on those old school turbo motors wasn't because of turbo sizing or tuning, it was because of compression ratio.  They're low compression motors, particularly compared to todays FI motors.  They're fine on the track, where it isn't as hard to keep them in boost but for auto-x they're just gonna suck.

The LS swap has some serious disadvantages in one of these chassis, mostly because of small frontal area for cooling and how narrow the engine bay is.  Granted I'm up at altitude so I have some environmental disadvantages that you may not have.  However I had to run the largest radiator that would fit, the largest oil cooler that would fit, drill holes in the bumper cover/beam, run hood vents and I'd still peg my oil temp gauge at 280 and regularly see water temps of 240-250.  I then added a secondary radiator that ran in series with the other one, but I sold the car before I could test it on track and see how it did.

The brakes are an issue, you can't run the vacuum booster so you either need to run manual, dual master cylinder setup or some sort of hydroboost setup.  I ran the Mustang hydroboost but for years nobody had an adapter to run the Porsche master cylinder so the brake bias was all messed up and modulating the pedal was really hard.  Texas Performance Concepts sells an adapter now.  Or you run the more expensive and complex hydroboost from an older BMW and the Porsche master cylinder bolts right up to it.

LS motors aren't anywhere near as cheap as they were when I did this swap close to 10 years ago.  Yes, you can still buy an iron block truck motor pretty cheap but by the time you've gotten the proper intake and F body accessories and accessory drive you might as well of just bought an LS from an F body or a GTO to begin with.  All the necessary parts for the swap aren't cheap.  Depending on your fabrication skills you may be able to make some, but others you'll have to buy.  Headers are an issue, the ones that are specifically made for this swap are, you guessed it, not cheap. 

I spent a metric ton of money on the swap to get it working, then working correctly for my high altitude environment and how I was using it, which was as a track car.  I wouldn't do it again.  In fact, I wouldn't do a non native swap like this again, ever.  The 1.8T swaps just weren't a thing when I did this but I'd do one of those in a heartbeat.  Everything fits, no worries with the brakes and you can make a ton of power on one of those with much less lag than the 951 motor or any of the old Audi motors.

yupididit
yupididit UberDork
4/29/20 11:19 p.m.

In reply to docwyte :

Re: LS swap, I feel like I read all this before lol. 

I'll look into 1.8's but i know nothing of them. 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/29/20 11:55 p.m.
yupididit said:

In reply to docwyte :

Tell me more about your LS swap efforts. Why wouldn't it run correctly? And what cost you the most? 

As far as lag, that can all be fixed with matching an appropriate turbo and parts + tuning. 

I know nothing of the 1.8 lol

I'm not sure what engine I'll eventually swap, I'm just brainstorming that. First I'd like to get the 2.0 running decently. 

 

 

 

The guy that bought my 450hp 951S detuned it to about 380 with a much smaller ball bearing turbo and autocrosses/hillclimbs with it quite well.

The big turbo that came on it when I bought it was nasty with lag, but good lord was it fun when it came on song.

I'm not a huge fan of the 944 engine, too overly complex and maintenance heavy compared to nearly any other option in similar sizes and configurations, but it can make some decent power for its age.  I wouldn't swap one into a 924 unless I had a wrecked donor and a bunch of time on my hands.  Then again I'd probably sell the engine and what I didn't want to use and buy a 1.8t or an AAN, etc.

L

i don't think you should rule out LS swaps, but being mindful of the potential challenges for track use will help.  Your challenges won't be the same as Doc's, though his are certainly valid, given his set of variables.

the 924/944 engine bay is actually wider than the 928 bay (by a couple of inches) and like a Miata, or any small car with a BIG engine, you have to make sure the air after the radiator is dealt with as much as the air coming into the nose.  So venting the hood should probably be done on track cars that run in high altitudes and/or high temps.

If you look at the 924 Turbo endurance car I posted, they run vents on the quarter panels and the hood along with some flat bottom work to help evacuate the air efficiently.  They don't run nearly the powe a 5.3 produces, but they run for 10-24 hours at a time so they need to keep temperatures under control.

yupididit
yupididit UberDork
4/30/20 5:08 a.m.

Okay, engine swap stuff is further down the road. 

 

I know a guy with 4 944's. Ranging from 84 to 89. Two of them are turbo two aren't, I know the 89 is none turbo. He's letting me take whatever suspension, brakes, etc. that I want for a couple hundred bucks.

I'm thinking go for the turbo front and rear suspension, spindles, hub, A-arms, rear trailing arms, and brakes/e-brake. Is there anything else I should grab?

 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
4/30/20 11:32 p.m.
yupididit said:

Okay, engine swap stuff is further down the road. 

 

I know a guy with 4 944's. Ranging from 84 to 89. Two of them are turbo two aren't, I know the 89 is none turbo. He's letting me take whatever suspension, brakes, etc. that I want for a couple hundred bucks.

I'm thinking go for the turbo front and rear suspension, spindles, hub, A-arms, rear trailing arms, and brakes/e-brake. Is there anything else I should grab?

 

If its an 89, it could have turbo brakes already.

Beware of the track width change along with the offset change.  You want to replicate the 924S suspension width, not the late 944.

If you want turbo brakes without 944 or CGT flares, you have to keep to the 86 Turbo uprights.  Period.  Also the aluminum front control arms suck.  Don't go there if you can avoid it.

You can grab the front calipers and rear suspension, you'll just have to change the rear hubs to the 924S pieces when you change the rear wheel bearings along with the matching rear rotors. 

Grab the metal brake lines and master cylinder to make the swap much easier.

Basically you need to set your car up with early offset 944 or 924S suspension (86 Turbo and 83-85.5 944, 86-88 924S)  Get late offset wheels (86-on 944 and 924S)

Here's a primer on what spring rates and sway bars come on what years:

http://www.clarks-garage.com/shop-manual/susp-15.htm

and here's what you can do for brake upgrades:

http://www.924board.org/viewtopic.php?p=218957#218957

The turbo exhaust can be an upgrade with a little work to mate them up.

The front and rear seats swap in as well.

The rear hatch swaps over

If you want to flare the fenders to fit wider rubber, then you can even swap the 944 or 951 front end in place with CGT rear flares.  The 951 nose and headlight covers are slightly different shape to the 944 pieces.

You can fit the later flush fit windshield, grab the wiper blades to match.  The rain gutters can move over as well, but you need to mount the plastic retainer clips to the body.

The oval turbo mirrors bolt up and work so, so much better.

There are some additional door seals that could be helpful as well.

The turbo torque tube and transaxle would be useful when it comes time to do an engine swap, since they can handle more power more easily.

yupididit
yupididit UberDork
5/1/20 9:53 a.m.

Alright, I'll get everything from the early 944 and the brakes from the 89. 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
5/1/20 10:45 a.m.

Yep, the front Brembos won't directly bolt to your early 944 uprights, but you can hold onto them while you search for some 86 turbo uprights to fit them to or find a solution (a couple of people were looking at making adapters).

The rears bolt up, but I would wait to do the fronts at the same time.

The stock 944 brakes are plenty for a 924 with good pads and a fresh rebuild.

Those calipers go for decent money, so at the very least they can help fund other improvements.

You might grab swaybars and springs as they'll likely be an improvement over the 924 bits, but that depends on whether other improvements have been made to your car and how much work you want to do on grabbing parts.

yupididit
yupididit UberDork
5/1/20 10:50 a.m.

In reply to Stefan (Forum Supporter) :

My buddy has a dozen or so sway bars sitting in his storage unit. 

yupididit
yupididit UberDork
5/1/20 10:59 a.m.

I was able to get Tunerstudio to communicate with the microsquirt. Unfortunately, I no longer gave access to my paid version of it. So, I'll just have to buy it again. 

The car idles a lot better now. When I drive it and give it too much throttle it starts backfiring. I just have to learn how to tune the rest of it so it can be more drivable. 

Also had a pretty significant fuel leak from the line that goes from the tank to the filter. Purchasing those soon. 

 

 

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
5/5/20 9:36 a.m.
yupididit
yupididit UberDork
5/5/20 11:49 a.m.

In reply to Stefan (Forum Supporter) :

Thank you, i happened to look at his thread last night.  

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
5/5/20 12:25 p.m.

In reply to yupididit :

Sounds like AE or Acceleration Enrichment isn't configured properly.

This article might help:

https://www.diyautotune.com/support/tech/other/accel-enrichment/

I just started tuning that on mine before something went tits up and the car sat for nearly a decade now :/ (mostly due to having kids, but there were other reasons)

yupididit
yupididit UberDork
5/5/20 12:41 p.m.

In reply to Stefan (Forum Supporter) :

I have that link up on my laptop. Just waiting to get some garage time. 

yupididit
yupididit UberDork
6/1/20 10:46 a.m.

My tps readings are so off compared to throttle input. I'll give it 1/4 or half throttle and it'll read something like 100-200%.

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
6/1/20 11:13 a.m.
yupididit said:

My tps readings are so off compared to throttle input. I'll give it 1/4 or half throttle and it'll read something like 100-200%.

You can reset the range of the TPS using TunerStudio.

Stampie (FS)
Stampie (FS) UltimaDork
6/1/20 11:54 a.m.
Stefan (Forum Supporter) said:

More pixxors of their 20Vt swap:

The Audi TT bellhousing spacer on a 924 Turbo bellhousing.  They welded them together for strength.

 

Sorry to thread jack but would that work on a 944 bellhousing?  I assume it bolts up to the vw/audi 4 cylinder (1.8T) pattern?

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
6/1/20 12:42 p.m.

In reply to Stampie (FS) :

Unfortunately, you'd need a bellhousing from the 924 turbo as the 944 engine uses a completely different bellhousing pattern.

Luckily, the bellhousings bolt to the torque tube in the same way, so you can swap the bellhousings around.

Stampie (FS)
Stampie (FS) UltimaDork
6/1/20 12:45 p.m.

In reply to Stefan (Forum Supporter) :

You're evil for making me think about the sitting 944 Turbo the next street over.  Thanks!

Stefan (Forum Supporter)
Stefan (Forum Supporter) MegaDork
6/1/20 1:23 p.m.
Stampie (FS) said:

In reply to Stefan (Forum Supporter) :

You're evil for making me think about the sitting 944 Turbo the next street over.  Thanks!

https://forums.pelicanparts.com/porsche-924-944-968-used-parts-sale-wanted/814259-unobtanium-931-bellhousing-wtt-regular-924-a.html

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