Semi-DIY Mild Engine Build for FI

[gsrboy]

Dave,

There's always negative things said about almost every valve springs. I would not let what you hear hold you back from using supertech. Just like some blame regrind cams for destroying their motor. Its either valve spring failure or the cams were not installed/degreed properly.


Tuan

 

[BATMANs]

....Are you putting new OEM keepers and retainers then? DAL broke OEM ones and ruined a few engines by reusing them. I'd highly recommend new ones! Why not new seats too?

I'm curious what rates the OEM ones are. If you run FI, and roughly estimate the valve area is 1.3in^2, then 10psi of boost would require stiffer springs (13 pounds) to compensate and ensure the same sealing force, even if you haven't changed camshafts or increased your engine speed......

My builder said that for the 4~ decades that he's been building engines he hasn't seen any keepers and retainers go bad after carefully inspecting the parts when it was taken apart.

In my case all of the parts in my engine were fine (aside from the failed pistons).


This is the first that I have heard about increasing valve spring pressures for boosted applications.

My thoughts are that if there is more boost that it would help open the valves and close the valves due to the increased dynamic charge.

I can see that logic with the exhaust valves. Are you talking about the exhaust valve springs?

 

[Mac Attack]

I know the OEM valves have a decent design, are hard to get new, and are expensive. Therefore, my rationale was to just reuse them if they measure OK.

I don't know the availability or price though for new valve springs, but I'll ask Acura tomorrow. If new OEM springs are the same cost of new Supertech's, then that's relatively cheap insurance and I'll buy new OEM springs. Likewise, I think it would be cheap insurance to get new retainers and keepers, especially when DAL had two good motors ruined because of reusing them:
http://ojas.net/nsx/mirror/dal#Heads

Oh, for FI, I think the intake valves would need increased spring rate as they're subjected to decreased dP WHEN that particular cylinder isn't firing on a particular stroke. Yes, on cylinders that are firing, I would agree the increased cylinder pressure should compensate!

On the exhaust side, I guess it would depend how well each cylinder communicated with the others. Couple a turbo that has a higher exhaust backpressure to begin with just from having to spin a turbine, to higher cylinder pressures from more power (that communicate with each other real easy like on the SOS twin turbo manifolds), and I would think you'd want a stiffer spring rate on the exhaust side too. I have no idea what the pressure is in a manifold, or what the increase in cylinder pressure is due to increasing power. Just sayin'. On a supercharged vehicle with really long primaries, then you could probably get by with a smaller exhaust valve spring rate....

Hmm, from the SOS website, if the 67lb seat pressure includes the ~20% increase, then the OEM seat pressure is ~56lbs. The SOS valves are then an increase of ~12lbs :smile: AHA!
http://www.scienceofspeed.com/products/engine_performance_products/NSX/ScienceofSpeed/valve_springs_retainers/

 

[BATMANs]

Just got the heads ports and blower manifold cleaned up and dropped them off for thermal dissipation coating on the intake ports and the outside of the heads and manifolds.

The exhaust and combustion chamber will get thermal barrier coating.

I'll provide close up and detailed photos later on as well as before and after porting and coatings.

 

[greenberet]

Just to follow up, as best I can tell based on the pictures in post #195, the intake openings in the cylinder heads each have an area of 21.17 cm2 not including the injector cutouts. Since the intake openings seem to be at an angle of 51.8° compared to the direction of the airflow, that would give the intake runners a cross section of 16.64 cm2 at that point.

That’s clearly the smallest cross section in the intake system, which will result in the highest airspeed being achieved at that point.

 

[Mac Attack]

I am so sorry - I forgot to get these for you. I'll try to do that this evening.

Dave

 

[BATMANs]

Just got the heads and manifold back with thermal dissipation coatings throughout except the exhaust port which is the thermal insulation coating.

 

[Mac Attack]

OOOoooohhhhh, Aaaaaahhhh... Looking good. Machine shop still has my stuff, but I knew they were backlogged a good two weeks when I dropped my parts off. Not in a hurry anyways.

Can you PM me the approximate cost for the head coatings and who did them please? I think those would look good with my black chrome valve covers.

Thanks!

 

[nsxnut]

Can you give us a rough idea what the thermal coatings cost?

Thanks in advance.

Later,
Don

 

[Mac Attack]

Swaintech will do the barrier coatings in 6cyl heads for $230, and exterior head dissipation coating for probably around $400 for both heads:

http://swaintech.com/store.asp?pid=10971

 

[BATMANs]

Can you give us a rough idea what the thermal coatings cost?

Thanks in advance.

Later,
Don

$300/head with both thermal barrier and dissipation coatings. It's very labor intensive on the time alone to mask things off, clean the surfaces with solvent and bead blasting, etc.

I'm using a proprietary coating from my connection at a Aerospace & Defense company that I'm sure many of you have heard of but i can't disclose.

The blend that I got isn't sold to the public nor available at Swain Tech, for example.

 

[BATMANs]

More pics with taken with my Nikon N90s SLR (prior to coating the heads):

 

[EAC]

where do the triangles go?

 

[sparky]

those images are amazing ... and huge, almost completely filling my 1,920 x 1080 screen. What resolution are they?

 

[BATMANs]

those images are amazing ... and huge, almost completely filling my 1,920 x 1080 screen. What resolution are they?

Dunno. It's the Kodak ektar 100 35mm film that was developed and scanned to a DVD at Costco. Yes it's old school like my nsx. More photos to come with the camera. Today im going to take pics of the engine getting balanced

 

[myhui]

I need to sneak in here with a question of my own, since this thread seems to be going so well. I'm working on an engine rebuild for my 2001 Prelude. I also have a 1999 NSX which I plan to work on next. The Prelude is the practice car. They both have FRM cylinder walls.

I need to check whether the FRM cylinder walls need honing, and if they do, where is a good place to get them done, preferably in SoCal, but I am willing to ship if justified.

Both the Prelude and the NSX have been using a lot of oil. The Prelude has oil dripping out the exhaust, so I believe that means the cylinders are running too "wet" and the oil control ring is not working. But looking at one piston here, how can I tell whether that is the problem? The oil ring looks fine: no breaks anywhere. One thing I've noticed is that the oil ring doesn't have any spring to it, unlike the two compression rings above it where they bounce out of the ring land by themselves the moment the piston is removed from the cylinder.

I plan to switch to Mahle's Gold Series pistons. They make ones especially for this Prelude model and they are meant for FRM cylinder walls. They make OEM-sized and 0.25mm-oversized versions. If the FRM cylinder walls are bored out by 0.25mm, will any of that special material be left?

http://www.us.mahle.com/MAHLE_North_America/en/Motorsports/Catalog

http://www.us.mahle.com/C1256F7900537A47/vwContentByKey/W26HSFB8505STULEN/$FILE/2010%20AP%20complete.pdf

Search for part H22220425F01 in the catalog above.

Does any shop have the necessary equipment to measure to 0.0016mm clearance? Or just slip the piston in the cylinder and do it by "feel"? The whole engine can seize up if I get this wrong. Yet if all else goes well (a huge "if", since so many things can go wrong), this is a key clearance measurement that can being top performance.

The cylinder walls look fine too, with uniform appearance in all 360 degrees of it and a super-smooth wall as far as I can see with my eyes and feel with my fingers.

 

[gsrboy]

Just got the heads and manifold back with thermal dissipation coatings throughout except the exhaust port which is the thermal insulation coating.

Batmans, your build is looking really nice man. Keep us updated.

 

[BATMANs]

Just got my cylinder walls fine honed 500 finish (280 is normal) where there is little to no break-in required. This finish is what Wiseco pistons requires to properly mate to the piston rings.

The block is perfetly straight up on top (never over-heated) so it didn't need to have the deck shaved.

These photos are taken with my brand new Samsung Galaxy 2 in case ya'll wondering.

 

[BATMANs]

.........They both have FRM cylinder walls.

I need to check whether the FRM cylinder walls need honing, and if they do, where is a good place to get them done, preferably in SoCal, but I am willing to ship if justified.

Both the Prelude and the NSX have been using a lot of oil. The Prelude has oil dripping out the exhaust, so I believe that means the cylinders are running too "wet" and the oil control ring is not working. But looking at one piston here, how can I tell whether that is the problem? The oil ring looks fine: no breaks anywhere. One thing I've noticed is that the oil ring doesn't have any spring to it, unlike the two compression rings above it where they bounce out of the ring land by themselves the moment the piston is removed from the cylinder.

I plan to switch to Mahle's Gold Series pistons. They make ones especially for this Prelude model and they are meant for FRM cylinder walls. They make OEM-sized and 0.25mm-oversized versions. If the FRM cylinder walls are bored out by 0.25mm, will any of that special material be left?

http://www.us.mahle.com/MAHLE_North_America/en/Motorsports/Catalog

http://www.us.mahle.com/C1256F7900537A47/vwContentByKey/W26HSFB8505STULEN/$FILE/2010%20AP%20complete.pdf

Search for part H22220425F01 in the catalog above.

Does any shop have the necessary equipment to measure to 0.0016mm clearance? Or just slip the piston in the cylinder and do it by "feel"? The whole engine can seize up if I get this wrong. Yet if all else goes well (a huge "if", since so many things can go wrong), this is a key clearance measurement that can being top performance.

The cylinder walls look fine too, with uniform appearance in all 360 degrees of it and a super-smooth wall as far as I can see with my eyes and feel with my fingers.

I dunno what FRM is. Please explain.

When I did my first engine build project (the GTO) I wasn't impressed with Mahle. To me it was better suited for the European car market. Normally aspirated.

Please advise me of what alloy the Mahle is (ie- 4032, 2618, 7075, etc.)

I did ALOT of research on carefully selecting my pistons (and other stuff) and IMHO the Wiseco Pistons were pretty much the superior choice. Certainly for forced induction applications. There just seems to be a vaste collective of history, racing experience, advance design, etc. that just made Wiseco stand way above the rest. JE Pistons were a distant second place for me and they were already good for a 1500HP GTR build that you can find on youtube running 8 seconds.

I dun have the knowledgebase to get into your aforementioned measurement specs. The best thing is for you to contact a shop for advise.

What engine oil and weight are you using? Do you properly warm up your cars? What is your change interval? What oild filter are you using and do you change it with each oil change?

I have owned a great many cars and have NEVER had ANY oil-related engine ailments as it appears to be in your case. ALl of my engine problems were a result of detonation (ie-bad gas, agressive and/or abject tune).

 

[kookoo4nsx]

FRM=Fiber Reinforced Metal

 

[BATMANs]

FRM=Fiber Reinforced Metal

What does it do?

 

[myhui]

Quoting http://en.wikipedia.org/wiki/Metal_matrix_composite

A metal matrix composite (MMC) is composite material with at least two constituent parts, one being a metal. The other material may be a different metal or another material, such as a ceramic or organic compound. When at least three materials are present, it is called a hybrid composite. An MMC is complementary to a cermet.

MMCs are made by dispersing a reinforcing material into a metal matrix. The reinforcement surface can be coated to prevent a chemical reaction with the matrix. For example, carbon fibers are commonly used in aluminum matrix to synthesize composites showing low density and high strength. However, carbon reacts with aluminum to generate a brittle and water-soluble compound Al4C3 on the surface of the fiber. To prevent this reaction, the carbon fibers are coated with nickel or titanium boride.

Honda has used aluminum metal matrix composite cylinder liners in some of their engines, including the B21A1, H22A and H23A, F20C and F22C, and the C32B used in the NSX.​

 

[BATMANs]

Interesting. I have a $3500 Griffin Vulcan bike frame made from metal matrix.

 

[BATMANs]

I was at the shop today and someone dropped off 2 Indy engines making 14k RPMs off for some work.

I should have photos of the rotating assembly being balanced tomorrow.

 

[BATMANs]

At over 110k miles my OEM harmonic dampener was inspected by my shop said that there are NO signs that requires it to be replaced.