posted on July 30, 2012 02:50
Team America World Time Attack - ARK Design's BNR32 Skyline GT-R Part 8
By Eric Hsu
Mike did a great job covering the build while I was unable to write because I was busy managing the car, team, and build and actually working on the car itself. From part 8 and on, I'll be taking over Beyond the Dyno once again. The car is on the slow boat to Australia, but for now I'll cover some of the things the team and I were doing at Cosworth.
Mike would head down to Design Craft once a week or so to see what was going on with the ARK GT-R, hang out, take pictures, watch Gary open Heinekens, point at stuff and say, "Hey, that''s pretty nice." or "Hmmm...I wouldn't do it like that." All while looking over his glasses in his patented monotone that could only be Mike Kojima. If it was something major that needed addressing, then Gary, Mike, and I would discuss and decide. If Tyler was there he would be in the discussion too, but a lot of times he was at home on Solidworks designing something (he claims!).
Here's Mike hard parking and looking above his glasses. He always jokes that he needs new glasses.
But there was a whole lot going on behind the scenes that was not covered in Mike's stories. A car consists of many sub-systems and they all cannot be built at a fabrication shop of course. The engines were built at Cosworth and the engine and chassis electrical harnesses were built at Apex Speed Technology, some of the aero parts were built at a surfboard shop down the street from Design Craft (but designed by Gary) in Huntington Beach, and the differentials were built at Cosworth. Unfortunately I was involved with most of the operations that took place at Cosworth which meant my hands were dirty/oily and I wasn't able to take as many pictures as I would have liked. So I'll cover what I have pictures on.
It all started with the used and beat to shit donor VQ35HR warranty engine that I acquired. It looked like the previous owner didn't change the oil and the engine was run for an extended amount of time at high oil temperatures. The crank bolt didn't want to come off no matter how much heat and torque I was able to give it. The solution? A 3/4" impact gun, a small nitrogen tank, and 250 psig of pressure.
Harbor Freight had 3 different 3/4" impact gun models: one with 400 ft/lb, a middle model pictured here with 650 ft/lb, and an ultra buff one with 900 ft/lb of loosening torque. The local Harbor Freight only had the 650 ft/lb model so that was going to have to do. With a MAPP gas torch and 110 psi (Cosworth's air pressure), the crank pulley bolt still wouldn't budge. That's when Lew suggested the nitrogen bottle. With about a minute of the MAPP gas torch flame and 250 psi of nitrogen, it finally broke loose. The threads were fine. It was just cooked to shit and stuck on there good.
Big pneumatic tools need a lot of volume too which sometimes people overlook. There were some giant air fittings and 1/2" air hose upstairs that came in real handy for this job.
Posted in: Magazine
, Beyond the Dyno
, Project Cars
, Race Cars
, XS Engineering BNR32 GT-R
, KW Suspensions
, Borg Warner
, Vibrant Performance
, Time Attack
, Time Attack Cars
, Skyline GT-R
, 2012 WTAC
, Project Nissan BNR32 Time Attack Skyline GT-R
, ARK Design BNR32
Monday, July 30, 2012 3:36 AM
Do those blocks use FRM cylinder liners or are they steel all the way through? It's hard to tell from the top picture on page 4.
Monday, July 30, 2012 3:53 AM
I was waiting for the engine part lol nice machine work that goes into Cosworths engines.
Monday, July 30, 2012 4:32 AM
The liners are iron and the aluminum is cast around the iron.
Monday, July 30, 2012 8:04 AM
Can i just ask what was the thinking behind not using all Cosworth parts in this build?
Monday, July 30, 2012 10:04 AM
@LeathanE, looks like Eric chose a custom length connecting rod and therefore needed a custom piece made. As for the cams, also seems to be custom specs, probably more race extreme than a typical Cosworth cam grind.
Monday, July 30, 2012 10:23 AM
These write ups are GOLD!
+/-.0003" bore tolerance is amazing. How do you measure it? Whats your hand lapping process like?
Photo-etching the head gasket layers will yield super flat and clean features. But if drilling them works, I guess that level of precision isn't needed.
Monday, July 30, 2012 11:36 AM
LeathanE: Cosoworth discontinued many VQ components due to the lack of sales. spdracerut is correct though: many of these parts are custom and not off the shelf so there wouldn't be Cosworth components anyhow. But they were designed by some of the same people who would have designed the Cosworth components anyhow. The cam are technically Cosworth, but just ground by Kelford. Unless it's for F1, Cosworth UK isn't going to drop everything and grind two sets of cams.
Max Machine: A dial bore gauge is used to measure the cylinder bores. The hand lapping process requires a whole story since there are two different methods used at Cosworth. Thanks for the tip on photo-etching, but for the water passages precision is not that critical.Water jetting or laser would be fine.
Monday, July 30, 2012 12:20 PM
t's really strange how Nissan made everything soooo similar between the DE and HR engine, but just SLIGHTLY different.
It's called capitalism, brah
The details on this engine are amazing, the cost of it must be insane!
Monday, July 30, 2012 12:22 PM
Thanks for clearing that up Eric and best of luck in Australia :)
Monday, July 30, 2012 12:55 PM
Hey now we've been using that Braille battery for nearly a year mate :)
Monday, July 30, 2012 2:04 PM
I like that you get in there and do some of the work too Eric. One thing though. Why in this entire write up was the crank never cleaned thoroughly, cylinder head and engine block never deburred and the oiling system not modified/dealt with in the way oil delivery is brought to the bearings and so forth? These are huge things that prove significant in keeping engines alive not only from FOD issues but lubrication scenarios as well. Its great you have someone like Katu doing some of the work as it can get very time consuming. My other question is that why did you opt to turn the valve down and loose overall cross section of the valve which equals air volume than fly cutting the pistons valve reliefs to clear the valve diameter/margins?
Im not trying to attack you or anyone that is doing the build but from one engine builder/machinist to another these are things that shouldn't be neglected or improvised upon.
I look forward to more writeups from you.
Monday, July 30, 2012 2:06 PM
also...what did you have the crank balanced at? What percentage?
Monday, July 30, 2012 3:01 PM
Thanks for the write-up Eric! I look forward to more articles.
Tech@EPR, read page 4 again for cleaning/deburring. They're using a dry sump setup so I imagine the lubrication will be covered later. Piston interference wasn't the problem with the valve- it was interference with the other valve, so larger reliefs wouldn't help.
Monday, July 30, 2012 3:53 PM
My mistake then on the valve interference between valve/valve contact, I was under the impression he had piston to valve contact. My main question about deburring had to do with the interior of the block more so than the exterior and the deck edges. Main web and saddle area to be specific. As for the crank, unless they removed the check ball out of the main oil galley (4 of them) the crank is not fully cleaned. If the check ball was removed and rifle brushed through every galley then great the crank is 100% clean of all sludge/coked oil inside. The oiling Im referring to has nothing to do with what type of pump is used I'm referring to the delivery in which the crankshaft is designed. Cross drilled cranks are the culprit for rod bearing failures at high RPM/loads.
Monday, July 30, 2012 4:35 PM
great article and pictures!
Monday, July 30, 2012 6:40 PM
Gotta love the stance-based pics with Mike, always make me laugh.
I am so pumped for the wtac this year, and hope everything works out smoothly in Au for you all and the car. Do you expect the Skyline will surpass Christine's 300+ ??? :D
As a US-based TA fan and major fan of TA in general, I am so excited to see the ARK bnr32 go the WTAC, but as an Evo-nut and SSE-fan, I gotta say I am still super bummed SSE did not continue developing their chunky gal.
On a side note: I know Nemo had two engines, but since the "poooof", I wonder if Nemo will only be bringing the one remaining engine?
Monday, July 30, 2012 10:19 PM
Eric: 1st, aren't you down in Australia finishing the car up, right now!? Less than 2 weeks! 2nd, You're the man :-)
Hey, what color did you guys decide to paint the still unnamed beauty?
Tuesday, July 31, 2012 3:09 AM
Motary: The cost is expensive, but engine #1 was built by Katsu and I on our free time so while there was less monetary cost, the cost was mainly our time. Engine #2 was built by Katsu on Cosworth time since they are one of the main sponsors. Yes, it would have cost a bundle if you put a price tag on it.
Mike: I didn't know you were running the Braille in total loss. OK, you're first, but they still read about it here first!
Tech@EPR: While we did not show picture of Katsu and I eating dinner, we most certainly did eat dinner. I didn't show a picture of Katsu putting the crank in the block either, but it most definitely is in the block. My point is while I did not picture the crank getting cleaned, it most definitely was cleaned thoroughly. I mentioned in the very beginning that I was unable to take as many pictures as I would have liked. Thorough cleaning is a must after WPC since the micro blast particles need to be entirely removed from the system. The media is finer than fine sand.
Likewise with the cylinder block and head castings. I believe I mentioned that deburring castings is standard Cosworth procedure.
I have never found factory VQ cranks to have any oiling issue. Have you? Then again I've never revved a stock crank VQ past 8500rpm. Many dry sumped VQs suffer from the lack of oil pressure because too small of a pressure stage is used. We will not have this problem because we are using an ultra wide pressure stage capable of over 22gpm.
eeeen: I'm not sure if the Skyline will surpass Christine's 301 km/h on the front straight since the Skyline has a much higher coefficient of drag to begin with. The Skyline will also have less peak horsepower by design, but it will certainly have a ton more torque. I'd say there's a good chance it might happen.
I too am bummed that SSE ended the program, but then again you never know if she'll reappear one day.
Nemo is a car to watch for sure. We'll see what happens.
Bruce: Uh...leaving soon. Paint? This thing is getting wrapped!
Tuesday, July 31, 2012 7:11 AM
Dropping knowledge as usual! Thanks a lot Eric, thanks for sharing your tricks, I'm learning a lot.
Tuesday, July 31, 2012 8:08 AM
Fun thing about total loss is using it in classes with a minimum weight. Why just use lead for ballast when there's these lead-acid ballast units that have other benefits too? :D
Tuesday, July 31, 2012 11:33 AM
Eric: I've never heard of hand lapping an engine block before. I did some googling, but couldn't come up with much specific info. Any chance you could go into this process in detail?
Tuesday, July 31, 2012 11:36 AM
You said the rev limit will be set at 8500rpm i heard with Christine you raised it to 9200? would you be able to do this safely with the Skyline if you needed the extra revs
Tuesday, July 31, 2012 3:53 PM
Diesel: Here's an old article I wrote in 2008 on my JDM Insider blog, before the days of MotoIQ on deck preparation: DECK PREPARATION
. This is the quicker way to do it. The super correct, and time consuming, way to do it is with a lapping table and lapping compound. As with anything, the more effort the better the results so lapping on a table is best.
LeathanE: The ARK Design GT-R benefits from custom gearing. Since Holinger has a whole giant chart of ratios to choose from, I was able to gear the car according to 8500rpm. Christine needed more revs because Quaife only has 2 different ratio sets for their EVO gearbox. Of course that's no fault of Quaife's since the gearset was only ever designed for Group N rally cars. So to get the additional speed, I had to raise the limiter to keep Dave happy.
Tuesday, July 31, 2012 7:19 PM
Awesome stuff Eric.
Great tips on an HR build which is next in line for my car. When I was fitting JWT C10 cams with high compression pistons Clark from JWT STRONGLY encouraged me to make a mechanical stop for the cam control, he felt that cam control (even with a Motec) was not precise enough and the engine would occasionally hit the mechanical stop, especially during high rates of engine acceleration where the cam control is liable to over-shoot.
I know the engine is already together, in the car and on the boat, but it may be something to consider for the future. I didn't have much time to do my motor, but we rushed something together in less than a day and it hasn't grenaded yet. Thanks for the amazing insight on building an HR.
Good luck to all of you!
Tuesday, July 31, 2012 8:01 PM
Epic write-up as usual! More and more pumped to cheer Team America on this year at WTAC! :-)
Wednesday, August 01, 2012 1:10 PM
Sasha: I've been told that before also regarding the mechanical stop for the cams, but none of those people used Pectel ECUs. I'm not say electronic controls can overcome the laws of physics, but Renault did use Pectel as the spec ECU in the Formula Renault 3.5 cars which use VQ35HR with twin variable cams that also rev to 8500. I suspect this is possible because the Pectel ECUs have a much more in depth PID control strategy for cam control. While Motecs are great, their PI strategy appears to be much simpler with simple single value P and I gains only. I don't recall seeing error based PID terms in the Motec. The stock ECU is great too up to 7000rpm, but Nissan's engineers never calibrated the stock ECU's PIDs to 8500rpm.
At one point, Renault was testing the dyno testing VHR engines using the Pectel ECU to control that mess of a valvetrain too. In my own experience, I've had no issues with controlling 4G63 MIVEC to 9000rpm and EJ20/25 AVCS with Pectel ECUs up to 8500rpm either, but those are entirely different engines of course.
Wednesday, August 01, 2012 6:45 PM
If you had the ability to choose custom gearing for the Evo, what would you have wanted Christine's rev limiter to have been?
I know you said you think the Skyline will ultimately be quicker around the track than the Evo, but its nice to know the insane speeds will also be there. Cosworth power! "HP" = "High Profit" right? Oh wait, no, that's not how that went... lol.
(I tried posting this yesterday, with no success, I hope it does not end up eventually multi-posting)
Thursday, August 02, 2012 12:30 AM
Sasha: Funny enough Clark at JWT sent me an email regarding the exhaust retarders after he read my response. He gave me some tips that I will definitely be using.
eeeen: The engine guy never wants to have to rev their engine any higher than necessary. That being said, the Sierra engines made peak power at about 8300rpm. Dave shifted higher in lower gears so that we could maximize 5th gear.
"HP" was my nickname within the Sierra Sierra team, but there really wasn't all that much profit if you really break down the amount of time the engineers, builders, and I spent on developing the engines.
Thursday, August 02, 2012 2:14 PM
Clark is a wealth of knowledge no doubt! I am greatful for all of his help.
I just wanted to say YES! Fuck NPT threads. O-ring boss feels so right. Do you know where I can find the machining dimensions for o-ring boss fittings?
Thanks and good luck guys, win!
Friday, August 03, 2012 1:13 AM
Eric, my statement is geared in the sense of a cross drilled crankshaft. There are several articles written about the design and its demise in throwing rod bearings due to oil issues. Makes no difference if its a VG or any other engine running a crossed drilled crankshaft, fact is, they are the death of any engine revving past the load/rpm they are designed to sustain themselves in.
I get that you didn't take pics of everything but I said what I did because you made NO mention of some of the things I spoke about. Im not here to tell you what is and isn't but I will say this that being a machininst and engine builder myself I know exactly what is and isn't and will and won't work for a lot of setups and scenarios. Im not here to nit pick nor pull your thunder out of this project. I had serious inquiries about certain things. Moving forward I look forward to seeing how this setup performs.
Friday, August 03, 2012 2:08 AM
Once again, I have not had issues with factory VQ cranks up to 8500. Have you experienced something I haven't? I know there are reported issues with high revving, long, cross drilled cranks; especially those with many cylinders such as American V8s, straight 6s, or V12s.
I personally have not had issues with cross drilled inline 6's to 9500 (RB26), V6s to 8500 (VQ35) and inline 4s to 10500 (B18) in sustained use. 8500 rpm is fairly low in the world of race engines. Many of Cosworth's race engine crankshafts are not cross drilled, but those are engines that see 10800rpm plus. I didn't think it was worth mentioning since I have not had any RPM related issues with cross drilled cranks as such a low RPM. Which is why I ask, "Have you?"
Saturday, August 04, 2012 12:58 AM
Regarding the lapping of the cylinder block, is it possible for the surface to be too smooth? How do you ensure that the roughness is in the correct range or are things different with metal gaskets?
Saturday, August 11, 2012 8:57 PM
Eric. Cross drilled whether V6, I6 or V8 its a known and inherent issue with the crankshafts oiling. It certainly isn't a matter "if" it will fail but "when". I machine cranks in house from oiling systems all the way to counterweight reshaping and windage reduction and first hand I've experienced oiling failures in nearly all platforms that utilize a cross drilled configuration. Many of the domestic manufactures don't use a cross drilled orientation for many reasons, the oiling distribution is one of them. Anytime you purchase an aftermarket crankshaft from Crower, Marine Crankshaft etc etc they (95%) will have a "straight shot" oiling configuration. Im only giving you my experience and expertise in what I've come in contact with and used and what I've done to resolve the issues. To date I've been 100% in resolving the oiling issue in the crankshafts distribution orientation. I know you've seen F1 crankshafts in person, you'd see first hand what oiling system they utilize. I only wish I could spend a week working with you to check out your work area. I envy your position in working at Cosworth.
Sunday, August 12, 2012 1:26 PM
Saturday, December 01, 2012 2:14 PM
I never did see your response until now, Tech@EPR. I'm now writing the Part 9 update for the ARK GT-R.
I do understand what you are saying and I know exactly what you mean regarding oiling problems of cross drilled crank pins. I have seen many race cranks at Cosworth that use different methods of oiling for sustained high RPM use. Also remember that there are several factors regarding how good or how bad a cross drilled crank is such as if the crank pin is fed by one or two mains, diameter of cross drilling, etc. I do not believe the issue will occur with the VQ crank and have proven so with the VQ35DE crank.
The first four years I worked at Cosworth were great, but sometimes I wonder why I didn't get out of there sooner than the six years I was there. I'm sure you've heard the news: Cosworth is for sale and the banks have stopped floating them (financially supporting them for an IPO). It sure was a great run...THE TELEGRAPH: Motoring company Cosworth puts itself for sale
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