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2443 Twin turbo street bug project, back on track again.
2443TT - November 17th, 2007 at 10:39 PM

Hi Everybody,

Well my 1966 bug has been off the road for more than a year now. What started out as some mild engine changes and a gearbox upgrade (that never eventuated), has turned into a complete rebuild of the car.

I've now got the car stripped of its guards, suspension removed, Porsche brakes are gone etc. All that remains is the shell and its sitting on stands.

The reason all this happened is that after a few conversations with Rod Penrose, I discovered I needed to change a lot more things to improve the reliability of my setup if I wanted to extract very serious HP from it for any extended period of time. This meant some serious engine changes... which then got a little out of control.

The end result of all the parts chasing, machining and custom made parts will be a 2443cc twin turbo'd, twin intercooled engine, water cooled heads, setup for sub 7:1 compression, flanged crank, 4 stage dry sump system, twin plate clutch, around 8500 rpm and potential for about 400-500rwhp. The engine build is on hold till the last of the machining work is finished and will be posted on another thread when it kicks into full swing.

Having that much power meant that using a vw gearbox was going to be pretty pointless. I'd been previously trying to source a custom built box from Rancho. That was for the 2332 engine, but as it turned out I would have probably broken that box inside a year anyway.

So the only option was to go porsche. 915 boxes are good for about 300hp, or more if you spend money on them. The g50's are massive, and require an absurd amount of cutting away of the chassis from what I've seen of other people cars. Unless I were to go 1/2 or full tube frame chassis, G50 was off the cards. I did come very close to getting a G50 though, and found a 2wd converted 5 speed for $4300 in sydney.

But as it turns out Dave Butler had a 930 box. It didnt take much to persuade him to sell it either. These boxes are used in the Ultima GTO's with 500hp small block V8's on them. In stock form they handle 550hp, and with an oil cooler and remote oil pump they are basically the same box used in the 750hp 935 race cars. At last an indestructable gearbox. THe down side is that the ratio's are very high, but that can be fixed with a ratio change down the track.

Now with an engine and gearbox sorted, I needed a way to get the power to the ground. It had been my plan to widen the guards and put some very serious rubber under the car. I've had the car that looks stock that goes like a rocket. Now Im going all out, the outward appearance is going to have to have as much intimidation factor as the engine sound will have.

To make all this possible I was going to have to completely re-work the suspension on the existing chassis, or just build a new one and start from scratch. I scored a swing axel chassis to use as a donor pan and went about cutting and clearancing for the gearbox.

So for suspension I've sourced all 1988 944 Turbo components. These are the widest rear trailing arms made for the 944's and increase the wheel track by around 100mm with the wheels I will be using.

The front suspension is going to be converted to a custom Mcpherson strut arrangement using 944 turbo A-Arms, and spindles etc. All the suspension is going to be fully adjustable, so I can set the car up for motokhana or drags. I want the car to handle, stop and go.

Anyway enough background... I've spend a few weekends contemplating how to best attack the new chassis and today I started to get serious with it.

930 Gearbox Clearancing
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00615.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00616.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00617.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00618.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00619.JPG

My unique approach to an IRS conversion.
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00677.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00680.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00681.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00682.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00683.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00684.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00685.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00687.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00692.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00693.JPG

Front gearbox mount/crossmember, and front torsion housing re-inforcing (the cardboard template).
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00688.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00689.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00690.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00691.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00695.JPG

So thats about all for now. I hope to finish the front gearbox mount tomorrow. Im going to try and make regular posts for this build. The goal is to have it finished in 5 months.

Cheers,

Ian Swinkels


Dasdubber - November 17th, 2007 at 11:15 PM

Great stuff Ian. I've been following along with your water jacketing questions and progress of the heads on shoptalkforums (I think that is where I saw most of the questions).....what are your ultimate goals performance wise (whether it be to reach a certain dyno figure, or certain ET/mph in the 1/4 etc)?

Obviously having bought your old 4x8 pwr water to air intercooler....what will you be running with the new twin intercooled setup?

Sounds all very interesting - I look forward to more info and pics/progress.
Alan


reub - November 17th, 2007 at 11:32 PM

Awesome to see the latest photos dude.
Will be a wicked ride when finished and I honestly look forward to seeing this post updated (just clicked the subscribe to thread :smilegrin:).
Keep up the great work.


LIFE IN THE LOW LANE - November 18th, 2007 at 08:01 AM

Could we possibly see this car make a journey down to Warwick next year???? sounds like a sight to be seen.....


bond - November 18th, 2007 at 10:07 AM

i got wood just reading the background info.

speechless ian. cant wait.

nick


2443TT - November 18th, 2007 at 11:48 AM

Quote:
Great stuff Ian. I've been following along with your water jacketing questions and progress of the heads on shoptalkforums (I think that is where I saw most of the questions).....what are your ultimate goals performance wise (whether it be to reach a certain dyno figure, or certain ET/mph in the 1/4 etc)?

Obviously having bought your old 4x8 pwr water to air intercooler....what will you be running with the new twin intercooled setup?


As a street car i'd like to see 0-100 in less than 4 seconds, a 10 second 1/4 mile on the RE55 semi-slicks the car will be running, at least 400 rwhp without NOS.

The Intercooers I have are air-air cores from a porsche 996. The are going to be mounted in the front of the rear guards.

Quote:
Could we possibly see this car make a journey down to Warwick next year???? sounds like a sight to be seen.....


I definatly want to make it to Warwick one day. I have a deal with Reub in that we both make it there the same year with our cars. I dont know when that will be though.


1303Steve - November 18th, 2007 at 10:27 PM

Hi

Nice work, good use of the leftover alloy bits from the spring plate covers. Are you moving the motor forward at all?

I considered a 930 box but after talking to Albins about suitable ratio gears it was more cost effective but not easier to go with a G50 plus you get 5 gears for all the hassles. Albins told me that some, if not all of the ratios are interchangeable with each other, ie move 3rd to 4th etc.

Steve


2443TT - November 18th, 2007 at 10:54 PM

Quote:
Nice work, good use of the leftover alloy bits from the spring plate covers. Are you moving the motor forward at all?



Yeah well seemed to make sense to use them. I priced some cheap engine mounts at repco first and they were too expensive for something that wasnt going to look quite right. I figure I have the alloy tig, so why not make an alloy cross member and use factory porsche body mounts.

Yeah a ratio change is definatly on the cards. at 8000 rpm i'll be able to so 62 mph in 1st gear according to the standard gear ratio calc. It will make launching the car interesting till i change the ratio's.


Cam - November 19th, 2007 at 01:12 PM

Wow! Looking awesome, Ian. Can't wait to see more pics as you progress.


2443TT - November 19th, 2007 at 08:09 PM

So its update time again. I made a reasonable amount of progress on the weekend. The front cross member design is more or less finished, although I do need to build up a lot more alloy around the mount ends of it. The moment i put it in place it immediatly squared up the gearbox mounting position. There is a 10mm alloy plate bolted to the factory front mounting position. This is the base for the front mount.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00697.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00698.JPG

And with the cross member roughly supporting it.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00699.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00700.JPG

Still got a little more alignment to do.
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00701.JPG

Front crossmember mounts are 1/2 done. I was able to use the pivot box plates as templates which made the job a lot easier. Just spot welded in place for the moment which is enough to support the gearbox barely.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00702.JPG
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00703.JPG

Here's a pic of the inner torsion housing brace cardboard template.
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00704.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00705.JPG

Wheel bearings arrived too. So i've put in the stub axels and drive shafts.
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00706.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00707.JPG

Next on the list is to finsih the front cross member, and then work on welding up the drive flanges from the gearbox with mild steel and re-machining them down to 90mm. Then re-drilling them and cuttig threads for the 944 turbo CV's. I looked into running 930 inner CV's and 944 outers, but that just isnt going to work because the axels would need to be custom. The 944 turbo CV's and axels will support over 500rwhp anyway, and the only reason they break on the 944's is because the diff assmebly gets a habit of moving around in the back of the 944's which changes the CV angles = CV death.

Waiting on brake rotors next, and an alignment tool so I can setup ideal camber on the rear end before welding the pivot boxes into place.

Cheers,

Ian


VWCOOL - November 19th, 2007 at 09:19 PM

I'm speechless...!


555bug - November 19th, 2007 at 09:24 PM

Ian,
what are you doing for brakes? something interesting I hope.

Stephen


avwboy - November 19th, 2007 at 09:30 PM

cant wait to follow the build , will be watching daily for updates as im sure alot of ppl will :)


2443TT - November 19th, 2007 at 09:40 PM

Quote:
Originally posted by 555bug
Ian,
what are you doing for brakes? something interesting I hope.

Stephen


Front and rear brake rotors should arrive this week. I've gone with Zimmerman 1988 944 turbo ventilated and cross drilled rotors. They are 300x28mm front and rear.

Calipers are 1988 944 turbo 4 piston brembo's.

Cheers,
Ian


kroozzn63 - November 19th, 2007 at 10:07 PM

wow thats some sweet hardware u got there cant wait to see its stance


2443TT - November 25th, 2007 at 07:33 PM

Well this weekend I finished off the gearbox front crossmember, and i've planned out the front A-Arm front suspension. The steel has been ordered and I'll be starting on the front end next weekend.

Here's a pic of the crossmemebr finished. I still need to make up the inside brackets for the bushing mounts but ill do that mid week.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00711.JPG

Cheers,
Ian


reub - November 25th, 2007 at 09:46 PM

Noting like someone who hooks in mate... :tu:


Dero - November 26th, 2007 at 03:14 AM

is t done yet :rolleyes:

WOW Sweet stuff, love it :crazy:


VWFREAK - November 26th, 2007 at 06:27 PM

Your crazy Ian, I love it, masssive HP =:blush::tu:


2443TT - December 2nd, 2007 at 09:56 PM

So here's the latest for my project. I didnt get a great deal acomplished this weekend as I had to work saturday till 2pm or so. On the bright side I live in an industrial area with noisy neigbours on both sides, so they arent game to come over and complain about me angle grinding at 9pm at night :D.

I finished the gearbox mounts at last. The flywheel end mount was made by cutting up my old rear mount that used a tie down strap around the bell housing, and basically moving everything around to accomodate the gearbox's larger bell housing. The location of the box sits about 1" higher than a vw box which will help with drive shaft angles and give me a little more ground clearance. I decided to use vw rear mounts in the end becuase they are CHEAP! and it just seems logical to try and keep as much vw stuff in there as possible.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00717.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00718.JPG

More clearancing around the inside of the frame horns to give a nice 1cm at least clearance around the gearbox.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00719.JPG

Front geabox mounts were finished bolted up tight and then re-tacked onto the chassis after moving the box around a little.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00720.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00721.JPG

After much deliberation on how to go about mounting the back end of the gearbox in the end I decided to weld some mounts that I fabriacted from 6mm plate. These were welded to the re-enforcing ribs on the bell housing on the gearbox, and drilled for mounting standard vw rear mounts. The nuts are done up with a spanner from outside the bell housing.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00722.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00723.JPG

A little more clearancing required when the frame horns get fully welded and all the notches get plated up.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00724.JPG

Heaps of room on the other side though.
http://users.on.net/~iswinkels/Hosted/Chassis/DSC00725.JPG

And from underneath.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00728.JPG

And with wheels lowered to about 150mm from ground to the front gearbox cross member.

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00729.JPG

http://users.on.net/~iswinkels/Hosted/Chassis/DSC00730.JPG

Im still waiting on rear disc brakes and my camber/caster measurement tools so none of the suspension mounts are welded into place yet. With any luck that will all arrive this week.

Still a fair bit more re-enforcing to do in the rear end yet, and also a decision about what kind of suspension to end up running will have to be made. I can still run torsion springs, or I could switch to adjustable coilovers which gives me a huge range of tunable features. I am leaning toward coilovers.

Thats all for now.

Cheers,
Ian


matberry - December 2nd, 2007 at 10:12 PM

Awesome mate.
Keep them ponies SCREAMING!!!!!

Matt


1303Steve - December 2nd, 2007 at 10:31 PM

Hi

That's a different way to mount the trailing arm pivot point. It looks a like lot less work your way. Are you using the stock 944 bushing?

Steve


Cam - December 2nd, 2007 at 10:33 PM

Unreal! You're doing an awesome job :cool:


2443TT - December 2nd, 2007 at 11:13 PM

Quote:
Originally posted by 1303Steve
Hi

That's a different way to mount the trailing arm pivot point. It looks a like lot less work your way. Are you using the stock 944 bushing?

Steve


Yes they are standard 944 pivot bushings. I considered switching to vw poly bushes for about 30 seconds. Then I saw the uniball conversion parts you can get to replace all the porsche ones with... front and rear suspension. They provide much better movement and dont interfere with setting up the base camber settings.

Thanks for the feedback. :D

Ian


mactaylor - December 3rd, 2007 at 07:44 AM

should be fun what ratios are in the 930? the one i drove was awesome, waiting, waiting then BOOST then lots of shuffling trying to keep it straight even with 15 X 10s. I dont think it did 62 mph in first though.


dangerous - December 3rd, 2007 at 08:00 AM

The stock four speed 930 first gear ratio is 2.25 with a 4.222 diff.


2443TT - December 3rd, 2007 at 09:10 AM

Yes ratios may cause a drivability problem. I am hoping the engine will make 7lb boost before 2000 rpm or so, so it should have a reasonable low end torque. The twin plate should be quite drivable too, unlike the 4 puck was.

Whether I will get away with this and the web 226 camshaft I will have to wait and see. To be competitvie in drag I'd really need to buy a new 1st gear and shuffel the rest along so 1st becomes 2nd etc. Aparently this can be done with the 930 boxes.


1303Steve - December 3rd, 2007 at 11:42 AM

Hi

If you have any CV trouble with 944 ones, I was able to fit 930 CVs in into the 944 alloy arms OK.

I considered a 930 box, these are the ratios that I found.

1st 16/36
2nd 23/30
3rd 28/25
4th 32/30
CW/P 9/38
These ratios are standard for all 930 gearboxes. The sport CW/P ratio is 8/41.

So 25.315 tyre 930 box
RPM kph
1000 13 23 32 45
2000 26 43 64 92
3000 39 66 97 137
4000 51 88 129 182
5000 64 111 161 228
6000 77 132 193 274

Steve


2443TT - December 3rd, 2007 at 01:28 PM

Quote:
Originally posted by 1303Steve
Hi

If you have any CV trouble with 944 ones, I was able to fit 930 CVs in into the 944 alloy arms OK.

Steve


I will be modifying the ouput flanges on the gearbox to suit the 944 CV's instead of going with 930 CV's and modifying the stub axel flange. The 944 turbo cv's and axels are good for 500hp so they will be plenty strong enough.

It would have been nice if the axels used the same splines as the 930 but 944 went another way. I did consider running custom axels with a 944 outer and 930 inner spline too. To make it a 100% bolt together affair.


1303Steve - December 3rd, 2007 at 02:37 PM

Hi

I have to get custom length axles anyway because of how much I've moved the transmission forward, but I went for the 930 CVs for their ability to run at greater angles. I'm really enjoying reading what your doing.

Steve