2084 Turbo Build

[kangaboy]

Are you getting the same cam with the correct blank?

Yep. I'm not super comfortable running the SC-1 cam with CBs lifters, and I don't want to go the tool steel route just yet. So I'll get the cam that I had initially decided on (with and EP-12 blank) and go from there.

[buguy]

Yeah i just had Web send me lifters with the cam. That way i knew they were compatible.

[kangaboy]

For anyone curious, my lack of updates is of no fault of my own...ordered the cam from WebCam back in March and still don't have a time frame of when I may get it. I called last week and they said they should be getting their new EP12 blanks mid-July...so we'll see what happens there. I'm almost to the point of them just sending me an 86b on whatever blank they have in stock, and then just getting a set of compatible lifter. I really had my heart set on the CB LightWeights that I have sitting on my bench, but it's almost to the point of what ever works.

[madmike]

March? screw that , my ADHD would of drove me nuts I really like the FK10 i have in the 2276

[kangaboy]

Quite the updated here. After a little deliberation, and WebCam still not getting the EP12 blanks in to make the custom cam that I requested, I just said screw it and had them send me back the initial cam that they ground for me on the SC1 blank (they still had it sitting on the shelf from when I sent it back to them initially ). Luckily, my lead engineer on this engine build, fellow STFer Jimmy Hoffa, had a set of WebCam lifters on hand from a previous build (that would be compatible with the SC1 blank). So while I'll have to shelf the CB Ultralights that I intended to use, we now have a paired cam and lifters ready to use.



With cam in hand, and all the thinkable parts on deck, I brought my boxes of parts over to Jim’s workshop and we started on the short block.



The case: We measured everything up on the CB/Autolina case and it looked awesome. Everything was in spec. 10mm studs with a deep #3, full flowed, previously hand deburred (with a little more by me), shuffle pinned, etc. After a short discussion on the Hoover Mod (cam oiling ports), Jim talked me into letting him drill a couple extra holes in the new case. After a quick measurement to make sure there was enough meat in the case, he made quick work of the additional ports while I was doing some additional deburring on the other case half. One more small modification was done to the case main bearing saddles, and that was just to drill out more of an oval shape to better align with the bearing outside oil ring. It was minimal, but better to move it where it can flow better, than to make it fight the direction you want it to go. I say minimal because there several folks that say as long as the case oil hole is at least half way exposed in the bearing oil groove, there is nothing to worry about. We had the opportunity to make it “right” so I opened it up a little bit in the case.



We had initially completed the blueprinting of the main bearings and new DPR crank a few months prior, so after a thorough cleaning of the case halves and crank, we were ready to heat up and assemble the cam/crank gears, and the #2 bearing, and then drop it in the case.



So this leads to the first major hurdle, or so it was thought...or is? IDK…anyway the DPR crank that Jose sent me was an old 1500cc crank that was originally straight drilled, and is thought to be the stronger of the stroker designed cranks for this reasoning. It doesn’t have any scallops on the main bearing oil ports, and from what I understand, the bearings used on these cranks initially had internal oil grooves. I believe SCAT is designing cranks currently that are straight drilled, but they have a groove around the entire surface of the crank to allow oil flow. My crank on top, a waterboxer crank on bottom for comparison. You can see the lack of scallop and this straight drill compared to the dual/scallop drilling.

[kangaboy]

Theoretically hit a wall here and stopped for a bit until we could find a path forward. Obviously searched the interwebs for a bit and found mixed reviews. Some obviously said we needed internal grooved bearings or it was going to starve #2 and #4 rod bearing of oil and seize up. Others said you’ll be fine with out it, and then others said just grab a pair of steel backed bearings and put the internal groove in yourself. So obviously there were mixed reviews…time to call the guy that sold me the crank and makes his living, literally, off of selling cranks. Jose was a little touchy on the subject…in a kinda joking way, but seemed appalled at the fact that I was questioning his work. I broke it down and explained my case, stating that I wasn’t questioning it, but more so just wanted the best path forward, and he said talk with any other actual engine builder that you know, and they will say its fine, as did Jose. I did in fact talk with my local VW shop, and he said the exact same thing Jose did (and also exclusively uses DPR cranks for all of his motors), and said there is nothing to worry about. Run it with the external groove bearings. Side note…we DID end up drilling a hole in the middle of the bearing halves in the external groove path…figured it wouldn’t hurt anything, and at the same time help us sleep at night, while also providing maybe JUUUUST a little more oil…maybe.



Alright, crank in and everyone is sleeping well at night, time for the cam. I went with CBs straight cut cam gear set, as it was suggested the 86B cam that I am going to run was on the upper limits of what a helical cam gear could handle. Figure just go with the sure thing and run straight cuts. I didn’t get any building pics, but the gear was installed at 0° straight up with no advance/retard, and then bearings were installed and everything was lubed up with WebCams packet of super sauce. Lifters clips installed on the top case half, and then its time to button up the short block.



I just needed to throw this in there for documented proof that the cam was installed correctly lol



On to the oil pump. Jim has the ability to put a nice o-ring on the pump, so he threw it on the vertical mill and now we have a nice, tight fitting 26mm Schadek oil pump.





The more I type the more I wish I would have taken more pictures…maybe next time.
Ok, short block buttoned up and torqued down. Everything still rotates, yay!

[kangaboy]

Time for pistons and cylinders. Took the 92mm JE pistons and their thick walled cylinders and gave them all a warm soap scrub in the bucket. Blew them down, gave the cylinders a little bbq paint base coat, and sprayed them with a little oil.





Rings gapped using specs for chrome top ring and a total seal second. Gapped and ready to get shoved back in the cylinders.





Pistons and cylinders ready to install. Next was assembling the new Scat 5.5 rods and their respective bearings. Just an FYI, putting 50lbs of torque on a rod bolt is boarder line sketchy. Rod bearing clearances were perfect with the Mahle bearings, so they were disassembled, lubed up, and torqued to spec on the crank. They all weighed the same to boot!





Next was the install of the pistons and cylinders. So all of this went just fine. I’m using the tru-arc retainers that JE pistons came with, as I feel they will be adequate despite several folks swearing that only one or the other works (aluminum wrist pin buttons, sprio-locks, etc.)



It wasn’t until we installed the head studs that we ran into a tiny problem. 10mm head studs are can be verrrrry tight on these 92mm thick wall AA cylinders. We got lucky on every stud except a one on the number 4 cylinder. No worries, the vertical mill can solve many a problem.





Alright, so we’ve almost gotten to the point of the current road block. I’m going to talk rocker geometry real quick, and then get on to the lovely discussion of Deck Height and Compression Ratio
So doing valve install in the heads was a breeze with the new handy dandy press we got from JBugs. A few little tweeks out of the box and its as good as you could imagine.



Got the intake and exhaust on the #1 cylinder and then went to measuring push rods. No pic, but we got our rod length and will throw them on the mill to cut the dual taper chromoly rods from CB to length. Next was bolting down a CB slipper foot 1.4:1 rocker down and taking it for a spin. After the lash cap and outside of the dual spring made some unfavorable seating sounds, the 86B cam measured just as advertised with ~0.532 lift.
Jim made the observation of the slipper foot maybe running a bit high on the lash cap, potentially creating some unfavorable wear on the guide, but after putting some gear paint on, it looked to not be too bad. With the mill, we have the ability to deck the rocker stands, but idk if its sever enough to do so…Thoughts?

[kangaboy]

Alright, the current issue at hand….

I pulled each cylinder down, got the dial indicator out to find TDC and got a deck height of .023” on the 3/4 side, and .028” on the 1/2 side. With the .016” step in the heads, that gives me .039” and .044” deck height. Nice…so now the bad part. With the 043 GO3 heads with 40x35.5 valves I’m using, they have an advertised combustion chamber cc of 52ish I think. After removal of the sharps and blending juuuust a little bit, we got 55cc for combustion chambers. This puts my compression ratio with 92mm pistons, 78.4mm stroke,.044 deck, and 55cc’s at 9.34:1. To high for my liking in a pump gas boosted car, with the option to use e85 during race day and just whenever I want.

Before cleanup:



After cleanup:



With Valves:



I need 67cc combustion chambers as it sits now with the current deck to get it down to a favorable 8.0:1. Every .01” addition to the deck height is comparable to 1cc…so even with a shim to .055” deck, I would still need ~66cc chambers.
Now is the part where pulling the trigger on the damn super squishies would have been critical. Other than that, I have heard every side of the argument on this one, from “don’t touch the combustion chambers cause you will ruin the flow while looking for cc’s”, to “just dish the pistons,” to “should have gotten head to suite the build”, and then back again to “unshroud the valves and take some meat out of the plug side.” Again…everyone has their opinion, but I’m about to just bust out the Dremel and find those 11cc’s, while trying to maintain the squish areas and not distorting the chamber shape much. You’ll notice on the above picture, I put some blue marker outlining the inside bore of the cylinder, as well as some areas around the valves where I think I can find some cc’s.

Anyway, as it stands now, I need to get my compression ratio to 8.0:1, and I have 8 days till the next track day…stay tuned to see if I make it.

[V8Nate]

Nice work:) I'm sure you'll find some meat to remove to get your cc's just right. What's going on in between the valves by your exhaust valve seat?

[Schweg]

I’m pulling for you!

[madmike]

don't be shy about a huge deck ,, that's why huge under cylinder spacer are made,,even the 'empi's' mic out pretty good

[Clonebug]

Aircooled.net states that cam requires 9.0-9.5:1 compression.

If you shim one side with a 0.10" shim and the other side with a .015" shim you will even them out as far as deck and your compression would be a 9.1:1 ratio. That's right in the recommended sweet spot for the cam.
If you put it down to 8.0:1 your off boost performance could suffer.

It has 300 degrees duration so there will be a fair amount of compression bleed off until it gets up to 3000 rpm.

I'd run it.

I've run .062" deck for 9 years.

[kangaboy]

Thanks guys...only 8 days to finish the long block, get all the top end and fueling system set up, tinware, break-in, tuning, etc. I feel like its quite a stretch, but were gonna give it our best shot. Just need to get these heads figured out and it's relatively all down hill from there.

Nate, IDK what up with that pic...there is a tiny bit of distortion in between the valves, but its smooth-ish...the weird looking picture doesn't do it any help. It is what it is. We buffed it up, so I hope it will be fine.

Mike, you are one of the folks in the "big deck is fine" club...I read through many of Clones replies stating the same thing as well...which is why I am not opposed to maybe getting as many cc's that I can appropriately find in those heads, and then making up for the rest of it with deck height. With the possibility to run "big" boost, I'm hesitant to dish the pistons as well. Wanna keep them as thick as possible.

Clone...so I'm aware of the ratios that John gives to each cam, but what are the criteria for such numbers? Are they assuming pump gas? Are they NA specific ratios? Why do I have it ingrained in my mind that I need to be as close to 8:1 as possible while running boost to not cause a catastrophe? Is that just a pump gas number? As you mentioned, I'm right on the money with the Aircooled.net suggestions, but I'm nervous with running big boost and a higher compression ratio. Am I just aiming for 11.5:1 AFR up top and hoping I don't detonate? I will say, I would turn my boost controller down to wastegate spring while I had pump gas in it, so ~8lbs of boost would hopefully be all it sees in that case. I would only do anything more than wastegate boost with E85 in the tank. I currently am not set up with an intercooler, and the thought of setting up a water/meth system has left my mind. For sake of future argument, lets say I run ~8psi on 93 octane, and 25+psi on E85 out of the pump with a flex fuel sensor. Lemme know what you think.

I appreciate the comments by all so far, and this is the reason I post my builds and serious questions on this forum...cause I respect the users and responses over here.

One last thing...I do plan to daily the car in the spring summer and fall as much as possible, and the only easy access e85 station is on the other end of my town, opposite my way to work. It just gets old driving out of the way to fill up 2-3 times a week. That's why I still wanna be able to daily it on 93 octane, which is readily available around here.

[Clonebug]

Boost limit is a matter of mostly boosted inlet air temps. Keep them as close to ambient and you can run higher numbers.
The higher the IAT's.....either ambient or boosted......the bigger chance you will experience detonation.
You do need good ignition control. Boost retard is needed any time inlet temps go over 110 degrees no matter the boost limit.

Travelling through the Hot Cali high deserts made a believer out of me. Both times I detected cruise detonation when I saw ambient temps at over 100 degrees. 100-105 ambient's would put my cruise temps at over 130 degrees..........without any boost ......most turbos will add 10-20 degrees just at cruise.
I had to lower my timing map at cruise and low boost due to very faint detonation.

The Intercooler Calculator on the RB Racing site is a good calculator to use often. It will tell you what to expect for IAT's due to high ambient temps or higher boost numbers. High Ambient temps and high boost are killer on engines that don't retard timing far enough.

As I still learn something new most every day.....the last trip I set up my MAT retard to lower timing at anything over 110 degrees. I never had any timing issues although we never hit the really high temps that were farther south. I never had that activated before since I seldom see temps that high with an intercooler and W/I.

If you are going to run boosted on the street I advise you to incorporate some form of intake cooling....whether it's an intercooler or W/I.
Colder air makes more hp.......in the long run W/I is a good investment and will save your engine.
If you run 8 lbs.at an ambient of 100 degrees your IAT's will be at 173*F. That's detonation territory unless you drop timing down to 20 degrees or less. 8 lbs. at 75 degrees ambient nets you 145*F. That's a pretty big difference just with ambient temps.
With my intercooler and W/I I can run 27-29 degrees timing at 8 lbs boost depending on rpm......my IAT's are still at 90 degrees or less depending on time of year.

Adding an intercooler was a challenge but it was still worth it. W/I will only do so much.......you'll turn it up...I know you will.
It is an addiction as you well know..........

My W/I tank is 1.0 gallon. I filled it up before I left for California.....I have driven over 2000 miles and the low level light hasn't come on yet....not even a little flash.

[madmike]

On my 2074cc I ended up with .106 deck and used .180 spacer,,,,why? , because I got a great deal on that Crank and the guy threw in the H-Beams & all new bearings,,,rods are 5.5 ,,, and I prefer short,,,, but it is what It is
I advanced the FK 8 cam 4* and "boy is this motor snappy/ power Frickin right now",whatever ya want to call it and that's "off boost"
I had a race coming up so I yanked it out and slapped in the 2180 so ,never really 'Boosted' the 2074,, well maybe 5 or 6 pounds only had a few miles on it ,,,, cheers, Madmike