9A pistons will give you a CR of about 9:1 with a stock headgasket. The ABA uses larger wrist pins so you have to get the rods rebushed for the smaller 9A wrist pin.
You'll still need the rest of the conversion parts: int shaft, pump gear, block off plate, intermediate shaft gear, crank gear, distro, etc.
You also need a Passat 16v auto throttle body to get a TPS.
You can run a 16v head off of Motronic, by swapping the 4 window trigger wheel in the distro for the ABA's single window. I'm not sure how that should line up so you should defnitely examine your stock ABA distro and how the trigger wheel lines up at TDC for refrence.
1995 GTI VR6 - 12.90@106 R32 power - 12.833@106 12v power
KPTuned - Official MegaSquirt: Sales - Repair - Installation - Tuning
Build Thread: The Build Thread "Good Clean Fun"
tried to find this info cant find it so i`ll ask when you run the mkIII accesories with the swap do you machine down the 16v pully or the aba pully and what all is involved in using the obd II system from the aba with the 16v head. also has any one heard of a valve clearence issuse when usin the aba pistons
why do you need to use the 9a oil pump and intermediate shaft? Why can't you leave the bottom end alone?
I am working on an ABA 16vT right now and I am going to go pick up a 1994 ABA motor tomorrow. I have a 1.8L 16vhead that I am going to put on it. Why should I change the oil pump?
You will have to forgive my ignorance, but I have been looking in the archives and haven't found an answer to my question. What CR do you get when you use an 95.5 crank, in an ABA block, with ABA rods, & 9A pistons? I would like to turbo the set up. Or do I need to use the 9A rods? Is a ABA piston taller from wrist pin to top than the 9A? Sorry is these sound like silly questions, but the help would be appreciated. Thanks.
ok, reasons to change the intermediate shaft are because the timing gear is wider and the ABA intermediate shaft doesn't fit the 16v intermediate shaft gear. The 16v intermedaiate shaft, from a 9A, fits right in and uses the correct width timing gear. Truth be told you can use the ABA oil pump with the 9A intermediate shaft, but the distributor is in the head on the 16v so having 2 distributors is unnnesesary. Therefore the 9A oil pump, drive gear and distributor hole plug are used.
If you wanted to go the other way to use the block distributor and block off the distributor on the head, you could get a block off plate from eurospeed.ca, the put the 9A intermediate shaft in the block and bolt a 16v cam gear in place of the intermediate gear, then leave your ABA oil pump and distributor, but then you may need longer wires, the distributor may hit the head and you may need to change the cam window between the 1 and 4 window style depending on what management you are using.
The 9A rods are way to short to use in the ABA block. Also using the 95.5 TDI crank with either 9A or ABA pistons will give you a fairly high compression ratio (somewhere in the 10.5-11.5:1) which will be too high for turbo.
Also you only gain .05L from the TDI crank, you could just turn up the boost 3 psi to get the same gain. Maybe if you use the ABA pistons and have them valve clearanced and them add a head space or several gaskets you can get the compression down enough for a turbo, or you could get eurospec sport ones for the ABF with an 95.5mm stroke and add a headspacer.
The cost of a TDI crank vs. the cost of an intercooler to use more boost, I know which one I would choose.
The ABA pistons are also shorter than the 9A pistons. Heres a good link to find your compression: http://not2fast.wryday.com/tur...shtml
Modified by all-starr-me at 1:00 AM 11-27-2004
Thanks for the tips Jason. You could get the compression down enough with a spacer and a head gasket on either side? I know they spacer a normal 16v motor to bring down the CR for boost. A 9A is like 10:1 right? See, I already have a 95.5 crank that is new, and JE pistons[9A] that are 83.5mm. I have all the internal 9A stuff I need. I just have to get a ABA. Hey do you ride BMX? I have friends that work at FBM by you. Thanks again.
The 9A pistons (rebushed) with ABA rods yield ~9.2:1 with an ABA crank, the TDi crank adds ~ 1 more point of compression so you would have ~10.2:1 (too high for turbo). What compression are your pistons for? 9A is 10.8:1 stock and yields ~10.2:1 in ABA with TDi crank so to approximate compression subtract 0.6 points from whatever your pistons are for.
You could prabably get the pistons dished out a little more by a machine shop, or just go with an EIP or C2 headspacer to get the compression your shooting for. I used to skate with some of the FBM guys, not so much anymore.
Wow, you just confused the crap out of me. LOL. It's hard to say but the pistons look like stock shaped JE's. I keep reading what you wrote and it's starting to make sense. Man I'm thick skulled. LOL. I want to get 8.5:1. I have to loose 2.'s of CR. Will deshrouding the valves and polishing the combustion chaber gain me some then maybe spacer it. Man, I hate to use a spacer.
Quote, originally posted by vwpat » The 9A pistons (rebushed) with ABA rods yield ~9.2:1 with an ABA crank, the TDi crank adds ~ 1 more point of compression so you would have ~10.2:1 (too high for turbo). What compression are your pistons for? 9A is 10.8:1 stock and yields ~10.2:1 in ABA with TDi crank so to approximate compression subtract 0.6 points from whatever your pistons are for.
Maybe if I dish the piston a little and deshroud the valves in the head I can make up 2.'s of CR. That seams like a lot to make up. Man this sucks! LOL.
Quote, originally posted by all-starr-me » You could prabably get the pistons dished out a little more by a machine shop, or just go with an EIP or C2 headspacer to get the compression your shooting for. I used to skate with some of the FBM guys, not so much anymore.
ive been readin this whole thing, and im still a little unclear. Im gunna turbo my setup, and i have a 1.8L 16v motor and an ABA tallblock. Am i set with parts? or do i still need the 9A intermediate shaft and sprocket, pump gear, and oil pump?
Modified by azninferno at 11:48 PM 11-28-2004
yes, you should be able to run it on motronic but it will be a little easier with OBD 1 than 2. You should have a chip made for it though, I hear techtonics makes them for ABF/16v ABA's, unless you are going with a turbo or supercharger them go with C2. You should make an adapter plate so you can use your OBD 2 throttle body unless you move the switches from it to a 16v one. You got the part about using a 16v cam gear on your intermediate shaft, right? Otherwise it wont turn at the right speed. Its a straight bolt on if you use a 9A intermediate shaft, otherwise you will have to mod the ABA intermediate shaft to get the 16v cam gear onto it.
Quote, originally posted by hasnfefr » Wow, you just confused the crap out of me. LOL. It's hard to say but the pistons look like stock shaped JE's. I keep reading what you wrote and it's starting to make sense. Man I'm thick skulled. LOL. I want to get 8.5:1. I have to loose 2.'s of CR. Will deshrouding the valves and polishing the combustion chaber gain me some then maybe spacer it. Man, I hate to use a spacer.
since you are going with a larger bore you could unshroud the valves all the way out to the new bore diameter, this should gain you some space to lower the compression but I'm not sure how much.
how far can i go with this with a chip before the system is maxed i want to run some boost or high compresion and some serious cams not sure which way is better i need to keep the stock ecu so that when i get tested for emisions they can still plug the car in if not it will fail damn MD laws
Ok, so I got my ABA engine tonight. I pulled the pan and oil pump, and the 16v oil pump and 8v oil pump are different. The 16v oil pump is driven by splines on its input shaft while the ABA oil pump is driven by a rectangle (for lack of better words) on top of its input shaft
The C2 chips are being used with the kinetics turbo kit. I saw it put down better than 350 whp on a turbo VR6, so chip tuning has potential, but you should really sit down and figure out before hand what your total budget is and how much power you need. If staying NA then I would get some sport cams, a 50mm or ABF intake manifold and eurospec sport pistons. If going turbo a stock manifold or short runner, stock or a euro intake cam and ABA or 9A pistons. Remember when going turbo though, take your total costs of all the parts, add them up then double that number at least for your total budget.
Modified by all-starr-me at 6:53 AM 12-31-2005
Quote, originally posted by all-starr-me » Well, you could try changing the input shafts, cutting the drive gear off the ABA distributor, or just leaving the distributor and living with it.
I could, or I could just get a 9a oil pump. I dont want to screw around with the oil system on the motor that costs more than my car. Just not worth the 80$ or whatever a new oil pump it
So I have started on the dis-assembly of my 94 ABA motor. I pulled the oil pan off 2 nights ago and had a b!tch of a time trying to get the actual pan off. Turn out that there was a windage tray in there, and it is bolted up to the oil pump. So if you are pulling your pan, separate the pan from the gasket, not the gasket from the block.
Ok, so next I put the engine on a engine stand. I removed the intake manifold from the head, no problems here.
Then I took off the valve cover, and some sorta plastic splash shield.
Since I am going to need to change the intermediate shaft, I figured it would be easiest to loosen the pulley while the timing belt was on. In order to get to the intermediate shaft, I needed to take the lower timing belt cover off. In order to take the timing belt cover off, I had to pull the crankshaft pulley. Now that the crankshaft pulley is off, I the timing belt is off too and I can't use that to resist the intermadiate shaft so I can take the pulley off. Then I look at the int shaft and notice that I can access it without removing the pulley.
Ok, So now I pull the head off. Easy!
I go to test fit the 16v head on the ABA block, and the guide pin is too big. So I pull/push the pin out of the ABA block, and put a pin in from my 9A block.
So that is where I am. In need of a 9A oil pump and all the gaskets and headbolts, but I'm very happy. The crosshatching on the cylinder walls looks mint.
pictures coming later!