1915 with AA 500 heads- now 2054

[buguy]

Ok since the 2275 is on hold for a bit, I figured I'd get the correct build thread stared.
The plan right now is to use a virgin mag case I already have and is bored for 94mm. Also going to use the stock rods and crank. Case has been thoroughly cleaned and galleys are tapped. Only thing I haven't tapped is the oil pump. I will also be reusing the flywheel, and the Web 163 cam and lifters. I will be putting the distributor drive back in this one so I can go full sequential.
I have a set of cast 94mm pistons and barrels, and now I have a set of real forged Mahles in the mail.
I am also going to reuse the intake system, intercooler, and turbo. However, I think I will be making a new header from 1.5" and taking off the 1 3/8".
As the title says, I think I'm going to buy mini wedge heads, 650 springs (maybe), and titanium retainers. I also think I'm going to try to use aluminum push rods if possible along with 1.25 rockers.
I polished the crank this morning and will be mocking up the crank in the case, balance the rods and get those fit to the crank, and get all that fit in the case this long weekend.

[madmike]

the price for good alm. push rods is like that 'Pearl paint' just get some chrome moly P.R.'s and C.M retainers. that's all I use , hold up great on the street,,,, leave all the super lite stuff for the racers trying to break records
use the Mahle's and your new cylinders,,check clearance.

[buguy]

My thoughts on aluminum push rods were really 2 fold. Being light is of course a good thing, but really I'm a weirdo about noise. I super like that my engine now is nice and quiet with aluminum push rods. Although I'm not sure how much of it I would hear over the 3" open exhaust pipe! I hear you though. I have a set of Mantons around here somewhere but they have already been assembled so it's unlikely they will be the correct length. I had them on my first stock engine I put the turbo on.
The engine builder at work said he would check my piston clearance and hone the cylinders if they needed it.
I tried to call and talk to Pat Downs about springs but he was out of the shop until 2 today. I saw that the 650 springs are an $80 upgrade so if I don't need them now I will wait and just get the duals.

[Clonebug]

I'm running just the outers of the 650 springs and I use the .035" wall CM pushrods. They are no louder than the stock pushrods.
I'm getting .530 lift right now so I see no reason you would need to run dual 650 springs if you aren't lifting much over .500".
Your cam with 1.25 rockers.....even 1.3 rockers will under or at .500".
Those springs would be major overkill and just destroy lifter bores or suck hp. That along with having to machine off a bunch of guide support.

[buguy]

Well I'm going to need them for sure when I build the 2276, so I may as well get them now. Or at least cut for them. I don't know if I could get the heads with them and take the inners out or not? If not I could just get regular duals and switch out to the 650's when I need them.
Yes. With 1.3 I think it was right at 500 lift. But I really don't know what it takes to control lots of boost. I will have to ask pat that if I ever get him on the phone.

[madmike]

reg,duals Like u said by the time you finally get the 2276 ready you'll need to get new ones anyhow

[buguy]

Ha! Pretty unlikely. It's summer here and already nearly 95 degrees. Makes it tough to want to go out for a cruise. I'd be lucky to put a few thousand miles a year on my car.

[Schweg]

Your in the exact opposite boat of pretty much everyone else. You build in the summer and play in the winter.

[Clonebug]

Well I'm going to need them for sure when I build the 2276, so I may as well get them now. Or at least cut for them. I don't know if I could get the heads with them and take the inners out or not? If not I could just get regular duals and switch out to the 650's when I need them.
Yes. With 1.3 I think it was right at 500 lift. But I really don't know what it takes to control lots of boost. I will have to ask pat that if I ever get him on the phone.

I haven't seen Pat running anything over about 12-14 lbs. boost on any of the engines on his dynos....just sayin........
For that matter CB usually doesn't even run an intercooler.

Boost really has no bearing on valve spring pressure due to having a 1:1 pressure ratio from the intake to the exhaust....and higher on the exhaust side in some cases if the turbo is a restriction.
Once you cut the valve guide bosses you will have to run dual springs in order to keep them from moving around.....

[buguy]

I would have thought boost would have a lot to do with spring pressure? The valve is working against that boost pressure and I would have thought it would need more pressure to keep it from bouncing around.
But your right I looked everywhere and nothing over 15 psi from them. I talked to him earlier and he said he puts 650's on all his turbo engines but didn't say why. And said he doesn't build small turbo engines. So that didn't really help me much. He also said he would run wedge port heads on a 2276 and would put a larger exhaust valve in it than comes standard (which is 37.5). Said it has a smaller port volume than the mini wedge, and out flows it, so it will have better air speed. Oddly enough he also said he would run the cam I already have in it. It's 250@50 and isn't too bad in my 1600. No way I would run that in a big stroker. I don't know if anyone has ever talked to him but he doesn't spend much time talking so it's pretty hard to get much info.
Chamber volume in that head is 67cc and would make for really low compression in a 1915 so I have some thinking to do.

[buguy]

Your in the exact opposite boat of pretty much everyone else. You build in the summer and play in the winter.

Building in the summer sucks too!

[Schweg]

Your in the exact opposite boat of pretty much everyone else. You build in the summer and play in the winter.

Building in the summer sucks too!

Either sweat or freeze.

As for Pat, I would think that similar to what clone is saying the valves should have equal pressure. Though valve size doesn’t 100% indicate flow rate.

Unfortunately the number of guys that have thrown large boost at a VW engine and drive on the street is as far as I can tell countable on two hands.

Looking foreword to the first drive report Monday!

[Clonebug]

I would have thought boost would have a lot to do with spring pressure? The valve is working against that boost pressure and I would have thought it would need more pressure to keep it from bouncing around.
But your right I looked everywhere and nothing over 15 psi from them. I talked to him earlier and he said he puts 650's on all his turbo engines but didn't say why. And said he doesn't build small turbo engines. So that didn't really help me much. He also said he would run wedge port heads on a 2276 and would put a larger exhaust valve in it than comes standard (which is 37.5). Said it has a smaller port volume than the mini wedge, and out flows it, so it will have better air speed. Oddly enough he also said he would run the cam I already have in it. It's 250@50 and isn't too bad in my 1600. No way I would run that in a big stroker. I don't know if anyone has ever talked to him but he doesn't spend much time talking so it's pretty hard to get much info.
Chamber volume in that head is 67cc and would make for really low compression in a 1915 so I have some thinking to do.

Those heads with a 67 cc chamber are designed for a 2276. You would need to flycut them to 60 cc's to get a decent compression ratio. Compression is dependent on cam duration and other factors. Trying to buy heads for two different engines is going to set you up with two piss poor performing engines.....You might as well just build the 2276 right away.

[buguy]

Oh yes. The valves will have equal pressure. I will surely still have to run high boost on the 1915. It's only a few hundred cc larger than what I have now. I don't think the impact will be enough to turn the boost down much. I think looking at CB's site might be confusing me more. His builds are all over the place with parts but I think the lowest I've seen is 300hp and the most was 330. That's not much of a change when some are little panchitos and some are super pros. There is a big difference in those heads.

[buguy]

Your right those are definitely for a 2276. But it would only be one piss poor engine. I wouldn't have them fly cut for the 1915. I would just run them set up for a stroker. I would just deal with what I got. The mini wedge is still on the table for me too.