Hey everybody. Couple of build questions out there. I have a 07 Mini Cooper S that currently lost compression on cylinder#3. Corrosion or bent valves none the less I figured it be a good time to pull the motor and do a built setup. Was thinking sneed for speed rods, super tech pistons ( looking for compression ratio suggestions). ARP head studs and main studs (seems to be mandatory?). Stock crank. Block and head are going to the machine shop etc. I was thinking going jcw exhaust manifold and jcw turbo portmatching the head also cleaning up the intake port. Stock valve train (obviously might upgrade later). Was thinking Rpm stage 3 software. Other question the car is Auto? Do the stock transmission hold stage 3 software ? Obviously all the other goodies Wagner engineering FMIC, catless down pipe l. Suggestions would be greatly appreciated. Not looking to make crazy power just reliable fun. Oh and obviously water/meth. Let me know what you guys think.

 

If changing pistons, go 77.5mm dia to ensure round cylinders. CR depends on max boost. JCW turbo can get by with JCW CR --- 10.0:1. As boost goes higher, CR should go lower. My 30PSI boost uses 9.0:1 CR.

What else??? Oversize exhaust pipes, for engine "breathability". Suggest Thumper for head work, he will also match the exhaust manifold to the head. Just remember, the gasket also needs to be enlarged, so if you ever change the gasket for any reason, you need to enlarge the new one yourself --- PITA! Don't forget OCC, dual is best.

 

So I should prolly just drop to the 9.5:1 if I think I might go bigger turbo one day? Have you heard any piston brands to stay away from? And with the ARP main studs are you guys getting the block relign bored.etc.

 

If you're not already locked in with a machine shop, and are considering 300+WHP, look at https://cylindersupportsystem.com/?f...R26x53-qiqMq0Q for beefing up the cylinder walls. They'll match diameter to the exact pistons you use, after installing their insert. Price is right and awesome warranty. Good turn-around too.

 

Following this thread, obviously.
I second oldbrokenwind's suggestion on the cylinder support system... it's the only thing I regret not doing when Buzz was being built the last time.

 

I’m assuming it’s like a block guard. It’s seems super reasonable for $395. I really doubt I’ll make anywhere near 300whp. Especially through an auto. I’m more concerned with choosing the proper compression ratio. Any thoughts ?

 

Hey was looking into CSS. Was curious if you guys could vouch for there other machine work? I’m not locked into a machine shop yet but I have a local guy I trust do all of my motors but he obviously doesn’t have the cylinder support system option (I assume it’s exclusive to css). But didn’t see anything on there website about boring etc. was curious if you Anyone had all there machine work done there or just the cylinder support system? Another question do the mains need line bored if I switch to ARP main studs?

 

I had them do the cylinder bore and CSS, no problems. They needed the pistons to ensure proper bore size, so a bit extra shipping cost. Should be no need to mess with the mains. BTW, CSS also sold me the ARP studs, his cost, no mark-up. Ask them about it, they're a good group to work with.

 

Ok awesome! I will prolly just have them do everything then. Still can’t decide on pistons yet. It’s either supertech 10.0:1 or I go cp 9.5:1. I’m leaning towards 9.5:1. Still haven’t heard anything about rods either. Sneed 4 speeds seem the cheapest for a forged h beam.

 

All aftermarket rods are not compatible with all aftermarket pistons, be careful when choosing them. I chose CP pistons and Carrillo rods 'cause they're from the same company. Also they were off-the-shelf. Sometimes SuperTech is out of stock.

 

Hmm maybe I’ll give sneed for speed a call make sure they are compatible or I’ll just go with the Carrillo rids.

 

Have you heard anything about the Mahle pistons ? The only CR I found was 10.25:1 ?

 

I've heard that Mahle is OEM supplier. They also seem to be less popular than SuperTech and CP Carrillo, based on build threads I've read. Don't know why --- materials, availability?

 

Hey figured I’d update this post since I got the Motor pulled this weekend. Turns out someone put an LKQ motor in this vehicle at some point. It looks like atleast 3 pistons hit exhaust valves. One valve definitely bent. One bent and broken (didn’t pull the head apart yet). 3 cylinders badly scored. I don’t know if 77.5 bore is going to get it out. But here’s some pictures of the carnage. So if anyone knows of a decent block laying around let me know.













ah that’ll buff out

 

Another picture of the cylinder wall.

 

The valve dome and the piston top are all looking good, only a slight film of carbon build-up. I remember when I pull my head out and first look scared me off, it was all gunked up with the valves and piston top has build-up which took me two-weeks hand-scrubbing them off (hobby time spent, not 8-hour work-day style).

After you clean it up and put it back together, it'll feel like a new motor. It's how mine felt, took all the shudders and shakes out of the equation just by cleaning up. Happy motoring.

 

Did you see the cylinder walls ?

 

Not really that much worried about cylinder walls. If you take a honing tool and hone the walls slightly to smoothen it out, you will be fine without having to worry about sleeving or changing to the next larger size piston. At least my cylinder wall didn't look like yours when I did it, and I didn't even hone it and it came out just fine, strong compression and all.

EDIT*: Nevermind what I said, just caught a glimpse of your close-up pic on that scratch. That scratch looks deep, and you will have some serious work to do if you are going to re-use the short block. In this case you will need to get some shop to cut your wall out and size up the piston to match. Else, you're looking at an engine swap. I don't think if you buff that scratch with some honing tool can actually get you squared away, you'll likely have some compression leak with it.

 

What are people’s opinions on using Darton 800-800 sleeves over the css option?

i am thinking css is a more cost effective option at $395 plus shipping compared to darton which is approx $700 plus labour charges.

 

Depends on the power the build you are building. Last time I checked CSS is good for up to 500bhp and Darton Sleeves for higher power builds than CSS can handle.

$700 for Darton sleeves is cheap as it costs double as much where I live. Labour costs to install them probably won't be.

 

Has anyone considered combining both approaches, ie sleeves with CSS. Would that bring anything extra to the party

 

If sleeves were done you won't need CSS as sleeves does more than what CSS alone can be done.

Extracted from a website

"The Darton Sleeves use a wet sleeve design that offers better cooling over standard open deck designs. The Darton Sleeves feature ‘Swirl Coolant Technology’ for significantly improved heat transfer in the upper cylinder wall area. This improvement in cooling reduces detonation in the combustion chamber which is one of the most common causes of engine failure among high performance, high horsepower engines. "

 

Hey guys been awhile sense I posted. Wanted to update this. Soo I went a picked up another motor. The story is the vacuum pump went bad broke the exhaust cam bolt for the timing sprocket etc. I have heard of this failure before seems common. Looked the motor over 2 bent valves in one of the cylinders. Obviously hit a piston. Didn’t see any other witness marks where valves met piston. Regardless all I really needed was the block and crank. I’ll take some better pictures tomorrow when I get it up on the engine stand disassemble it completely etc. was told the motor had 89k on it.


On a side note I am really curious about the Darton sleeves. The pricing I have found is around 1200$ just for the sleeves and I’d have to find a machine shop that can do it. I’m sure the labor will be considerably expensive as well. But I mean I guess with a block like mine where the cylinder wall is scored beyond a .5mm bore that’s really my only option or scrap the block?

 

Last year I got a price quote for Darton sleeves and install ~£2000 here in the UK, but just couldn't justify myself spending that much whilst only aiming for 300bhp.

Maybe WMI setup would be a cheaper and better option for me.

If you're thinking of more bhp and can get the Darton sleeves done at a reasonable price then it's a good option as I've only heard good thing about them.

Keep the post updated with your build ​​​​​​​.

 

Well my one block is junk so if I ever want to use it I’d have to sleeve it. Not solely for the strength. My cylinder walls are just scratched to deep for a bore.

If your looking to just strength the block cylinders. There is a couple companies that will close deck the N14’s block. And it’s super reasonable compared to the Darton sleeves.