911SC Turbo

[juicersr]

Ben, latest progress? Pix?

[iamchappy]

Here is the latest edition to my engine rebuild using the 3.3 turbo pistons and cylinders and twin plug heads. Courtesy of Henry at Supertec.

[juicersr]

Chappy, is that based on an SC core? Is your engine stock SC case/ internals? What HP you aiming for (did you dyno you last engine before starting rebuild) Thanks

[iamchappy]

My engine is in the building process, I am using the 3.0 79 SC engine with 1991 3.3 turbo pistons and cylinders using my stock rods with Arp rod bolts and 928 rod nuts with Supertecs rod wrist pin bushing modification to accommodate the different wrist pin size and rod length. This will make a 3.12 running in the low to mid 7's for compression depending on deck height. I should be able to run 1 bar with the intercooler and twinplug. I am using Supertec head studs as well. And will continue to use my BAE bonnets until I decide to fabricate something else. I haven't had the problem of blowing the bonnet off like Suter, but I am using a T-bolt hose clamp.

[Turbo-Mag]

For anyone who has a copy of the BAE Manual. Can I get a copy emailed to me?

dsielken@aol.com

I just got my basket case running and now working on future plans

[Turbo-Mag]

A big thanks to chappy fast reply



Thanks again man

[sammyg2]

LOL this thread just won't go away

[quattrorunner]

I have read this thread about the bae kits and other threads that also apply. My question is one that never really was answered completly. What about adapting the stock sc exhaust with a turbo flange on a test pipe. Is the stock sc thick enough to withstand the rise in temp? Looks lots like the 930 exhaust in design. If it would work, it would be simple! I basicly have all that would be needed for the exhaust at least. Mine is a 79 so I guess it could be mostly a bolt on affair. I'm not that close really as I would like to crack the case and upgrade/update whatever needs attention first. I just thought I could get this question out there. TIA

[tsuter]

Sure just take the SC test pipe and extend it back and behind the driver side chain cover. Add engine mounting brackets for support and flanges for the turbo and wastegate. You have now essentially fabricated the BAE header to turbo pipe for the turbo using the test pipe as a starting point although I'm not sure its worth buying a test pipe...cheaper just to fabricate the whole thing.

Make sure the turbo mounts in the same position as BAE so you can use the I/O pipes or similar to the 930. Not in the wheel well. Read other threads about mounting turbos in the wheel well.

Then take the stock muffler and shorten it about 10 inches. Is that even possible?? (won't fit with turbo in position) and then weld on a mounting flange to the shortened muffler so it will mount to the turbo. I doubt this can be done. Any 930 or aftermarket 930 exhaust muffler will fit with possibly a flange change.

That's about it....

[quattrorunner]

Thanks, my test pipe was already hacked and a bosail muffler is attached now sounds great by the way.

[Elu]

omg!!! You guys are awesome and crazy at the same time. About half way through this my eyes glazed over. So I don't know if this was mentioned, but how much would the total cost on something like this run for a 74 2.7L 911? It looks like you guys have spent a mint...not to mention decades doing the work. I want one!

[sammyg2]

My total cost to purchase the used BAE kit, install it, and tune it was around $1200.
That's around $10 per hp
Yes I did get a very good deal on it, and yes others have gotten much more detailed and advanced than my system, but it can be done with relatively low cost and without spending a great deal of time doing it.
Unfortunately boost is like a drug, all it takes to make us happy is a little more.........
We start out with a simple and low boost system and then we start tinkering and tweaking until we can crank the boost up just a little more.
At that point it can get expensive and time consuming.

[quattrorunner]

Does anyone with more experience with cis than myself know if this is a cheep enrichment? It appers to bolt on. It is on ebay but these are almost free at audi graveyards. This looks exciting.
8069936259

[laughac]

I paid $1575 for my BAE kit. It did not come with instructions, but I found 944 instructions online, and imchappy has told me he will email me the 911 instructions.

If I don't alter the kit, will I need to adjust my CIS to run richer? I have a '77 with no O2 sensor. Also, if I just run the low "stock" BAE boost, can I leave my pop-off valve alone? I'm nervous about blowing up the airbox.

[tsuter]

Originally posted by laughac
If I don't alter the kit, will I need to adjust my CIS to run richer? I have a '77 with no O2 sensor. Also, if I just run the low "stock" BAE boost, can I leave my pop-off valve alone? I'm nervous about blowing up the airbox.

No and No.

No, you don't alter your CIS mixture with a turbo. You add supplemental enrichment if over 6psi.

And no, you cannot use a pop valve. You must epoxy it shut or buy a new airbox with no pop valve. Then don't blow it up.....

[laughac]

The two biggest risks for engine failure caused by a turbo seem to be:
1. Over-revving (got a rev-limiter rotor)
2. Lean mixture - especially under boost

Is it safe to assume the BAE kit won't generate more than 5 psi, or do I need to monitor the boost. (Hmmm... I think I just asked a really dumb question...) Is www.slowboyracing.com a reasonable place to buy a boost gauge?

[iamchappy]

These work great for sealing the airbox pop valve.

[laughac]

Look poifect

[SLO-BOB]

Originally posted by tsuter
No and No.



And no, you cannot use a pop valve. You must epoxy it shut or buy a new airbox with no pop valve. Then don't blow it up.....

C'mon Thad-post another pic of your garage fix for pop-off valves.

[iamchappy]

My engine is almost done I cant wait to hear it, Varoom.. FLAPPPPP, PSSSST again.

Those plumber test plugs really do work great. Way better than the epoxy solution and only takes a minute to install, and are good to over 10bar .