Yamaducci's 2498 cc Turbo Re-Build Thread

[jhoefer]

[BDubVdub]

[808OvalGreasemonkey]

I am curious,the bolts that are holding the cam gear on "look" like super cheap "chinee" bolts with no grade marking on them (?) I am no expert,but that is something I would not overlook.
You mentioned Tec3,who is going to tune that for you? It is a complicated laptop based system. Here is a video of a car that went on the dyno and started off with 401whp. With the exact same boost,I took out a little bit of fuel and added more timing advance and made an additional 62whp. I did this in one dyno session using that SDS system I mentioned earlier,it was so easy to program the changes and see what the engine was doing. Check it out,I am only posting this becasue you like turbo VW's ,and THIS is a turbo VW! You can build the best engine in the world,but it is all in the afr & timing curve.
http://www.youtube.com/watch?v=84H2Z9VpyHM

[yamaducci]

[808OvalGreasemonkey]

Sorry,I had no idea you had EFI already. I thought you were still on the suck through carb setup,my bad. If you are dealing with experienced tuners,then you are on the right track. The only thing is when you need to make changes for drivability and startup/idle/cruise,that is when it gets difficult unless you are very familiar with the system.
The cars I built are all street cars and are daily drivable with over 500bhp on tap,and that was through hours of street tuning for transient response/cruise afr,etc. Have fun. I have seen a lot of hardware in my business and those bolts just "looked" cheap to me....have fun and get boostin'!

[VIN]

maybe his "weiner budget" couldnt afford Grade 8 bolts...

[yamaducci]

SAE says:

3 Radial Lines = Grade 5
Medium Carbon Steel, Quenched and Tempered
1/4" thru 1"= 85,000 92,000 120,000 Lb's Tensile strength.

I think the Engineers did their homework.
_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[yamaducci]

[jhoefer]

[yamaducci]

Weekend worked on the Fin addition to the Competition Eliminator Heads (see my other thread on that).
http://www.thesamba.com/vw/forum/viewtopic.php?t=476890




_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[yamaducci]

OK so I put of ton of pictures in my gallery last night of two CB Performance F.I. intake manifolds. One was bone stock, completely raw and the other was after the Fluff & Buff.
You should be able to see the difference but I will point it out to be clear. This method can be done on head ports as well; just remove the guides for best results and to avoid embedding grit into the Bronze.

Raw Intake Runner

These are the casting seems you want to get rid of. A full mirror polish is not wanted especially with large ports. You want it to flow smoothly but still have a texture to keep the molecules bouncing through and suspended.

Raw Intake

Raw Intake Exterior

Raw Intake Exterior



I started with the Carbide cutter bit for non-ferrous metal (wide blade) then moved to course rolls, then to the medium rolls then went to the course cross buffs and finally, the medium cross buffs (tool links in previous post)





Here I took a gasket that was used when porting the head and transferred it to the manifold. You can use a sharpie or Dykem and then scribe through it to outline where you need to cut/sand. These are now match ported to my Competition Eliminator Head ports.


Fluffed Intake Runners


Side-By-Side Comparison




Side-By-Side Comparison

After the final buff with the cross buffs the exterior of the manifolds were much shinier. Since I did not want to go with a fully poished manifold I knocked the sheen off and evened the texture with a "Fine" Grey Scotch-Bright pad.
Working time was about 2 hours for two manifolds with a Rotozip with the guide removed. Going to a full polish on th inside and outside would take another 8 hours without rushing and doing it right.

Once complete; washing with Mean Grean degreaser brightened up the Aluminum.

This is just one level of potential. Let me know if you have questions.
_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[yamaducci]

Update: Back on the build project after a few other long projects but will be building with the as-is CE heads to get base line temps before adding fins. That individual thread can be followed here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=476890
_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[mark tucker]

just a few things, you are only using 1 path for oil.the cooler bypass.dont do that. get a 1/2" aluminum plate the size to bolt down to the cooler adaptor pad on the case, drill it to fit, get the bug pack gasket, cut a section out of it 1/2" from one port to the other port, then transfer that to the aluminum plate, then use a ballend mill and cut a trough through the aluminum plate aprox 3/8 deep from hole to hole. you now have 2 paths for the oil to go, and you dont have to plug the holes in the case for the valve to breathe if you still use a soft spring & piston.or pluge the breathing hole (in the cam chamber)and no spring&piston.

This will do 2 things: 1 give 2 flow paths so there isant any chance of restriction due to turning corners&going through bad flowing orfices. and the main thing it will do, is the slow down the oil in the main gally due to it being fed from 2 places.at high rpm high flow rates can pass right by a oil gally& not feed it, but actuly suck oil from it!!!yes just like a ventouri, but , nainly just reduce the amount or possiably cavatate the oilo as it passes the gally at high speed going to other destonations or pressure relief.
and I would rather the rod throws be drilled than the counter weights be drilled, remember the reason for adding the counterweights to be added?? now that is almost gone.it should of had the throws drilled befor adding the counter weights.and it makes for a much lighter crank and is still strong with less chance of flexing like the stock crank does.I had a 86 bb crank hear and there was allkinds of crap (slivers/bendovers)hanging off the thing where it was machined & not properly deburred,& 1 oil hole almost nonexsistant,1/8" dremel with carbide ball workd great for that work. keep up the good work!!!

[yamaducci]

[yamaducci]

Current Update: After many hours of trying to avoid more machine work to the Competition Eliminator heads. I decided to find a new machine shop to remove material from my rocker pads. No combination of shims and lash caps could reasonably correct the rocker arm geometry. The combination of Autocraft 1.4 ratio rockers and Competition Eliminator just would not work without machining (estimated .030-.040") off the rocker mounting pads. I will post geometry at "0" lift when I receive the heads. FYI:When the adjuster is at the pushrod side; the first step is get the contact point of rocker arm to valve tip below valve centerline on the valve by ~ .060" @ zero lift.

These rockers and Heads will be worth the added effort once they are perfect. If they are not set up perfect they are a ticking time-bomb.
Another note: I discovered I could, instead of using rocker arm spray bars, drill each rocker arm and use CB Performance Tool Steel adjuster screws for a fully oiled rocker assembly. It would provide pressurized oil up until it reaches the needle bearings in the rocker arm. The down-side would be pressing out all 8 needle bearing cages to drill the rocker and pray none of them are damaged.
_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[mark tucker]

I dont think that 1/8"will do much for duel path. you dont need the seals for the plate just the bugpack gasket that replaces the seals.if the hole is still in the bypass gally in the cam chambetr that will just squirt you oil in there not putting it to the bearings.or you have to plug the piston galy so oil will not go there.or use the spring&piston but you are not using the upper gally unless you add the plate across the holes you have pluged. I sure dont want to see you mess any thing up, by either bypassing or not bypassing some portion that needs to be used.and for the pressure you can use one of the adjustable plugs(yes they look like poop, but work.or you could make one that is much nicer and have a real seal on it.it's easy to over look something or think it through almost all the way and miss something. kinda like the bugpack bottom feeder(oil fitting) that lets oil pressure bleed off through the vacume break hole in the bypass chanel& the hole in the case for the piston is too small ,(pressure hole)you dont need any internal leeks that are covered up by a high pressure spring,exsessive foaming,over filling of the camchamber,and oil gally bleed down when turned off resulting in longer runtime getting oil to all parts when starting,(aka long dry start, like when changing oil filter &draining cooler).
I usualy cut down the rocker blocks, not the heads, but either way will do the same thing.also if the rockers need moved you can make an incert like is sold for the ones that pull studs, and just move the stud to where you need it to be.
if you drill the rocker for oiling with needel bearings the cage will block off the new hole unless you add a groove around to the tip end then to the sides with washers/spacers that will deflect the oil to the needles.I drill my bushed rockers for tip oiling & add a groove in the bush to it.

[mark tucker]

I also drill the cam oiling gally coming off the main gally (where the plug is in the side of the case )biger dia, to be sure there is plenty supply.and be very carful widening the slot in the cambearing journel/ toweres, one of those comes very close to the edge&clrearncing relief, you dont need to loose any oil pressure there either.I had thought about conesting the rear cam bearing gally to the lifter gally, but it's very thin on the mag cases, I might see if it is feeseable on the aluminum cases. the more gallys tied togeather the slower the oil go's, it cools better and works better .

[yamaducci]

Mark, I took a look at my Block-off plate last night and you are right. No OEM style oil seals just a flat gasket. Here is a pic:

I think I will consider using this; however, before I do I could run an oil pressure gauge to the 1/2 side cam journal at first to see what running a plugged cooler and oil booster springs will give me (as Bob Hoover Suggests). If there is good pressure throughout the RPM and load range then it would be safe to say having the single path of increased pressure will be OK. If not, that could indicate oil in the main galleys passing right by the entrance to each main and cam galley as you mentioned before from oil velocity being too high.
Here is a pic of where the 1/8" NPT hole is in the 1/2 side of the case where oil will be returning to the cam journal #2 or it can be used as a test pressure port.




For others following along we are discussing the oil circuit in the following diagram. My additional modification are in Red. The oil control modification allows the preper use of a 30mm High Volume oil pump. This port was opened to 8mm to allow pressure to bleed-off faster than stock configuration. The second Red line is a 1/8" NPT drill and tap into the #2 Cam Journal to allow added oil from an external line or a pressure test port.




Here is a shot of the completed Bob Hoover HVX mods done to the lower valve train in addition to my modifications. Notice the added groove in the lifter bore, #2 /#3 cam journal drilled for oiling mod "D" in diagram above.


_________________
-John Cox
My 2498 Turbo Re-Build Thread: http://www.thesamba.com/vw/forum/viewtopic.php?p=5578697#5578697
Cox Racing Engines
Class 5-1600's; Stock 1600 to 2498cc Type 1's. Custom Built for you in Maryland

[nsracing]

That is the weak side you just tapped. The lifters only get the tiny amount of lube there. You just need drops to lube the lifter bores there.

You should tap the MAIN GALLEY-SIDE for any oiling application ..gauge or other lube enhancements you might conjure up.
_________________
"A free people can only afford to make this mistake ONCE."

"..from my cold dead hands."

"An unjust law is no law at all."

[yamaducci]