LT5 bare block

[tpepmeie]

Maybe the last LT5 "virgin" block in the world. Who wants a 700bhp / 380 cu. in. engine?

In all seriousness, I am using this block to develop the liners and block machining program for new liners. I'd like to offer aluminum nikasil coated liners up to 4.000, and ductile iron closed deck out to 4.130 bore. The designs are being worked up.


http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_7018.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_7018.jpg.html)

http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_7019.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_7019.jpg.html)

[Blue Flame Restorations]

Neat stuff, Todd

[Paul Workman]

:happy1:

I'm interested! Do keep us in the loop!

Paul.

AES has done a few closed deck LT5s; Bob Gillig's 427, Al Dashto and Kevin Costello's 441s (cranks came from Bryant, IIRC). I don't know if that would interest you - save having to do some of that machining - or NOT (I dunno). But, the 4.000 nikasil liners are VERY interesting, especially if the machining to the block was minimal.

My pending build plan would be a sleeve and cam re-grind - NO offset grind on the crank seriously being considered at the moment. Being able to have 4" nikasil aluminum sleeves...would be ideal for what I would hope to be a very reliable upgrade.

[A26B]

Great concept Todd.

Rebuilding the LT5 with new rings & sleeves is becoming a vanishing possibility. The first item to go extinct will be rings, then sleeves & new pistons.

For several years now, I have been toying with the idea of developing a major overhaul kit comprised of new sleeves, pistons & rings, with an increase in bore to 4.00". I see no reason to rebuild with a stock 3.90: bore. I am glad you are doing this and I would be glad to refer my customers to you for those parts or buy from you for my customers.

[tpepmeie]

Jerry,
the problem with an aluminum liner is getting enough wall thickness at the bottom. You cannot go less than .120, or the liner won't have the necessary stiffness, at least I wouldn't feel comfortable less than that. I have a Cosworth XD wet liner which is .120". Stock LT5 is about .135".

An iron liner can go .080" or even less because of the stiffness of the material.

If I go ahead with the Aluminum liners, the OD would be oversize and thus require the bottom of the block to be machined larger. This shouldn't be a big deal for most competent machine shops. Nonetheless, a 4.000 aluminum liner wouldn't be a "drop-in" replacement.

So, why bother? Well, a couple of reasons, mainly the same that Lotus decided. 1) lighter weight-not a big deal for most of us, 2) better wear resistance, and 3) friction reduction again due to the properties of the coating.

[tpepmeie]

Cosworth liners and the OEM LT5 liners. Guess which is which :)

http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_0271.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_0271.jpg.html)

http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_0270.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_0270.jpg.html)

[W i l l]

Hi Todd, I think there is a speck of dirt on the floor.... Just kidding. Nice shop!!

[W i l l]

Since aluminum 4.00" liners would not have enough wall thickness, would it be possible to machine the liners from titanium (for strength) and line them with Nikasil (for wear resistance) to avoid machining the block? Not that I have anything against deflowering virgins..., but just looking for an alternative to block shock :)

[tpepmeie]

Will, I don't think Ti would be a very good liner material, and I am not aware of anybody who uses it. From what I understand, the surface properties aren't well suited to any application which involves rubbing or friction.

I'd still like to concentrate on the Aluminum liners, but I'm not sure there is much of a market there. The cost would be more than twice what the LA sleeve iron liners are because of the nikasil coating, plus the additional block machining. For a 4.00 bore at nearly any moderate performance level it's hard to beat the economics of the good old ductile iron sleeve. LA Sleeve sells these for $145 ea. retail and they drop right in.

Hopefully I can have something new to display at BG this year. Whether it will be iron or Al, I'm not sure yet.

[Paul Workman]

Looking forward to seeing you and your creation!:cheers:

[spork2367]

Was this the one that Jim Butler Chevrolet had for sale? I actually have a virgin block sitting on the shelf in my garage. I'd love to see someone remake nikisil plated liners.

[tpepmeie]

RE: aluminum liners.

I believe I could offer Aluminum nikasil coated liners in 4.000 bore at approximately $2500. You would need the block bored slightly oversize to accommodate the liners, and the final honing would need diamond abrasives.

Benefits- Lighter weight than iron, superior wear resistance, lower friction coefficient.

Can you guys let me know either here, or by PM whether you might be interested.

[Jitse]

Hello Todd,

I am interested in a closed deck 4" Sleeve set, the steel version, something similair like you are now using on your own engine.

Two weeks ago I finalized the rebuild of my 368, but discovered the day after I filled it up with coolant, there was coolwater leakage from inside the oil pan.
Toke the oil pan of and saw immidatly the problem, there was coolant slowly sweating from in between a few liners and the block.
Dissambled the engine and found that the sealer from the liners was complete washed away.
The block was send away before to a locally good recommended machine shop,
But from my view now; not that good at all.
They ultrasonic cleaned the block including the liners and after that the installed a torque plate and honed the sleeves ( iron ductile).... the result you know :(
I provided them with all the technical data (copies) from the service manual, but looks like they did not read and made a short cut. A expensive one for me.

I never want to go back to this shop again and I am going to search for a shop who can handle this job how it suppose to be.

Todd are your design closed deck sleeves still using anaerobic sealer or did you make an modification to o-rings in to the block. I like the closed deck because of the more ridgit design it looks like its also possible to get a thicker wall sleeve in to the block with not that much extra job for a good cnc machinist.

Jitse Betsema

[tpepmeie]

Jitse,
PM sent

[XfireZ51]

Cosworth liners and the OEM LT5 liners. Guess which is which :)

http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_0271.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_0271.jpg.html)

http://i1036.photobucket.com/albums/a441/tpepmeie/IMG_0270.jpg (http://s1036.photobucket.com/user/tpepmeie/media/IMG_0270.jpg.html)

So Todd, is that Cosworth as in C7 ZR1 Cosworth? :eusa_shhh:eusa_shhh

[rkreigh]

the nikasil is certainly great stuff and adds to the durability of the LT5 bores.

But can't you just get the ductile iron liners coated?

Seems like it would be lower price and still meet your 4.0 goals

I'd love to see how much it would cost to nikasil coat a set of AES liners.

That seems like it might be feasible.

[george1945]

The pictures of the bare block quickly dispel any thoughts of the LT5 as just having a set of trick dual OHC heads slapped on. The more I learn about this beast, the more I come to appreciate it and respect just how special it really is. I just wonder where the HP would peak on a built, streatable driver in a natural aspiration and a turbo boosted variety. 700-800 HP and up? Easy?

[tpepmeie]

the nikasil is certainly great stuff and adds to the durability of the LT5 bores.

But can't you just get the ductile iron liners coated?

Seems like it would be lower price and still meet your 4.0 goals

I'd love to see how much it would cost to nikasil coat a set of AES liners.

That seems like it might be feasible.

Ron,
Although you can coat ductile iron, there is no real engineering benefit to doing to. The aluminum is coated for wear resistance, which is obviously not a problem with iron. There is a slight side benefit of friction reduction, but that is really secondary to the main purpose. I can't think of one example, either in production or motorsports with a nikasil coated iron liner. Somebody might prove me wrong, but it's generally not done.

[Hog]

Yes, the whole point of a Nikasil liner is to allow the aluminum to stand up to the rings frictional wear forces.
No aluminum cylinder, no need for Nikasil. The advantage is the aluminum liner, the Nikasil merely allows its usage.

[spork2367]

Ron,
Although you can coat ductile iron, there is no real engineering benefit to doing to. The aluminum is coated for wear resistance, which is obviously not a problem with iron. There is a slight side benefit of friction reduction, but that is really secondary to the main purpose. I can't think of one example, either in production or motorsports with a nikasil coated iron liner. Somebody might prove me wrong, but it's generally not done.

I was just reading back through some old posts looking for some info on rings and found this.

Some air cooled forged 4140 aircraft cylinders are nikasil plated.

[rkreigh]

Thanks all! Nikasil is cool stuff. I agree that the ductile iron liners might not benefit all that much but it seems that nikasil would make them a bit slicker and reduce friction. The rotex guys are the only ones I see nikasil coat a ductile iron sleeve and I believe they do it just to get that "last little bit" of durability.


The ford guys "plasma spray" the alum block which seems to be a pretty advanced treatment.


Thanks for pushing the envelope and explaining the engineering!

[spork2367]

Thanks all! Nikasil is cool stuff. I agree that the ductile iron liners might not benefit all that much but it seems that nikasil would make them a bit slicker and reduce friction. The rotex guys are the only ones I see nikasil coat a ductile iron sleeve and I believe they do it just to get that "last little bit" of durability.


The ford guys "plasma spray" the alum block which seems to be a pretty advanced treatment.


Thanks for pushing the envelope and explaining the engineering!

We have also used the plasma spray coatings on aluminum blocks. It is probably a better coating for aluminum today than nikasil.