[davejcb]

Buying a 91 TSI AWD within 2-3 weeks... Got the car for 1100$, body is mint, tranny looks good, only prob is bottom end needs rebuild, pistons 1 & 3 are busted. Head is still ok.

Now. If I were to build the engine like so:

Stock Knife Edged Crank
Crower or Pauter rods
Ross or JE Forged .010 Over Pistons
Ross or JE rings
Balance Shafts Removed
Engine Completely Internally Balanced
ARP Head Studs
Clevite 77 bearings
Ported head, extrude-honed, 5 angle valve job
1.0mm oversized Valves
Web racing springs with titanium retainers
Web Race Cams 453/228 grind
New lifters
New timing belt and tensioner
New water pump

That's all I can think of off the top of my head, but if I were to run this on a 14b, 450cc's, free mods, stock exhaust, stock pump, and everything otherwise stock until I get some $$$ to upgrade...

Would it run like shit? Say I had an AFC to control the idle with the cams, what other problems could I run into. I know this is doing it ass-backwards, but it's either this or rebuilding with stock 91 rods, 95+ pistons, and ARP head studs... I do plan to run 11s or more eventually, so I am thinking just build it right away. I will have all winter to do this, so downtime is not a problem.

 

[dsm4eva]

It'll run fine, but you need to do fuel upgrades when you add a larger turbo. As an aside, some people complain of excessive piston slap with the forged pistons, just something to keep in mind.

 

[davejcb]

Cool. Think that's what I'll do then.

 

[Nick 92 TSi AWD]

You shouldn't have any real problems except for the lumpy idle.
How high do you plan on revving it and how often will it be at high rpms?

 

[davejcb]

Don't plan on revving it any higher than 7000rpms... Will probably shift at 6500rpms when racing. Why, you don't think the titanium valve springs would be necessary then?

 

[eto]

If your going to shift at 6500, you might as well get a stock block and stay with the 14B turbo. If you get a large turbo, shifting that low will hurt your times. Those cams are also extremely aggressive. They are made for a drag car shifting at 8500+ RPMs. Its highly likely that the car will stall whenever you get on the brakes hard, due to a lack of vacuum. They recommend a stand alone engine management system to control those cams.

 

[davejcb]

Yeah but do you really need to shift that high??? Isn't all your power from 3500 to like 7500 on a 20G?

 

[ForestTalonAWD]

Dude, why are you wasting your money on springs/retainers when you plan on shifting so low?? You can usually take the STOCK valvetrain to 7500 rpm ... Is there a reason you don't want to shift at higher rpm's?

Ti or not, though, the only thing that would cause you a problem would be the cams you mentioned. Those cams are meant for racecars that only go WOT, they're not designed for daily driving, i.e. idling, coasting, etc. If you went with the Web 546/547 cams (which will still easily support 11's), you probably won't have any problems at all.

Good luck,

 

[davejcb]

Thanks for the info. Yeah, I think the 546/547 will be a good choice, I still want to be able to drive the car around, even if it won't be a daily driver. I just didn't think there was that much power to be made at such high rpms on a DSM, guess I was wrong

I do plan on getting a 20G or FP Green not too far down the road, so I guess that I may as well go with the springs anyway/cams.

 

[Rdy2race]

not to bust balls but this isn't much of a advanced question.

I will move this to Gen tech after this post.

Some things you have not outlined is compression for one.

I see no reason that a 95 piston motor wouldnt be ok for 11's and the others are a nice touch but things like the cams and springs can be added later for the sake of a better running car in the mean time. With the huge changes in the car that you will make with valve size, compression, Cams and so on your only risking damage with out the proper control. Do the lowerend of the motor if you like. the rods and pistions are a good idea and the other parts need to be looked at. Like the valves for one. 1MM over means that the seats need to be cut. this is a cost problem and larger isn't always better. With the larger valves it's more weight and this means a heavier spring is needed to return the valves fast enough. With that said this combo is also a High RPM combo. shifting at 6500 is not a option as your not in the powerband long enough and shifting this early will bring the motor down to a RPm where it's not making much power. Anyhing below 4K RPM's with this setup will be about the same if not less power then factory. So unless you plain on reving it higher save the money for other parts like fuel control. A ballanced combo will be much nicer then a high priced mis-match. I do not agree that you will not have problems. for one is the way the the ECU is going to react. with the low flow at idle B/C of low Vac the car will be dumping fuel. with this the fuel blocks ( trim ) will be low as it is trying to correct but as you open the car up the car will be in lack of fuel. making for a gas hog that doesn't get out of it's way. Nothing is worse then spending the cash and not having the outcome be something nice.

So i would make it a bit more mild. Drop the SS valves and the 5 angle V job. the cams are nice but do not need spings and retainers. and if the outline is for a 7K rpm motor I feel you will be better off with factory 1G cams. the new lifters is a must IMHO for any rebuilt motor and a new front case cover and oil pump gears.


Many have gone in to the mid 11's with 95 pistions. Yes the JE's and rods would be nice but needed? No Not IMHO

Best of luck with the project.
BM-

 

[niterydr]

imo stay away from the headwork until you need a bigger turbo..also if you only intend for 11's, street grind cams will help you alot.
Imo, go w/ .020" over pistons, that's the optimum size for the valve size among other things within our cars (i've had a few engine classes..its alot to explain, just go w/me on this one).
also if you like boost, go w/ 8.5:1 compression pistions instead of 9.0:1..and remember the higher compression + boost=more fuel or you get dedination.
good luck

 

[davejcb]

Thanks for all the info Bill and niterydr. Think I'll start off small then, I'll just rebuild the bottom with some 9.0:1 95+ pistons and 91 rods for now.

About the head though, if I were to take the same head I'm getting with the car, and has 215 000km on it, what would be best to do? Assuming the valves are all ok, should I go with the 3 or 5 angle VJ? Do I need to have all the seats reground? What about porting? Leave that for later or do it right now? New lifters for sure, what about springs?

Thanks!