Engine and Transmission Tech

Good News!

Good news,
Now we need some updates

An update on DiDueColpi, otherwise known as Fred. Good news, Fred is alive and well! I had a long conversation with him late this afternoon (BC time). He and Mrs. Key took a 2 month holiday in Europe, swore off electronics for the trip and says that he hasn't got back into the swing of posting things since his return.
He is still working on some of his projects and said that he will be posting again in the future but that he has enjoyed the freedom from the internet.
I have missed following him and his projects on this site.

Phil

Great News! Thanks, Phil!

It would probably do most of us a world of good to spend less time on electronic distractions. Real life is out there & it is not waiting...

Well The mystery is solved Way to go Phil aka Sherlock ps how did you get him to answer a phone?

Hi Fred!

How's that Unicorn coming along?

Bump for Fred?

I’ve been looking at going down a similar path with an engine build, as described in this thread.

I’ve been looking for piston/rod combos that work with the 28cc rover head, and either a 4.0, 4.6, or offset ground 4.6 crank. Using a custom spreadsheet, the best results come pistons with low 20’s dish cc’s, short piston heights, and 6” or longer rods as needed. Some combos offer mid-10’s compression, 40thou squish/quench (does the perimeter ring quench matter with a dished piston?), and over 1.8 rod ratio. JE makes some, but they’re not plug-in easy -different pin sizes, etc. and they’re pricy.

Using the 305 pistons and rods, using -12 to -14cc pistons I can get a reasonable compression, but the piston needs to be way down in the hole, like over 80thou. I’ve been assuming about 3cc’s of extra volume for combustion chamber porting work.

What trade offs would you go with? Grind the combustion chamber some (lots) more, or give up on getting a decent quench, to use off the shelf parts?

If you need more combustion chamber use the Buick 300 heads.

I have spent many, many hours over the years playing with the various combinations using the calculators below. I have come to the conclusion that it is most likely cheaper & certainly easier just to bite the bullet & buy custom pistons rather than try to use off the shelf pistons.

[uempistons.com]

"use the Buick 300 heads"

I've been looking around for some, but haven't seen any in the last several months in the places I know to look. (some came up on eBay maybe two months ago, with an intake, for around $1k. I thought that was steep. Before I was really looking, I saw some earlier in the $300 range, which I'm kicking myself for not getting...) Where do the people on this site find them??

Brian McMillan has quite a few parts to sell. He will probably post here and on the Mgexperience site.



Edited 1 time(s). Last edit at 06/13/2021 06:34PM by mgb260.

It is worth noting that the SBB iron heads are just 35 lbs heavier than the aluminum 300 heads for the pair. They also have larger ports and valves. I have a set of iron heads on the Buick 300 currently in my '71 MGB which I just drove to the V8 meet and was quite satisfied with the performance. It was just about what you would expect from a stock 9:1 compression 300 ci engine of that era, specs are 210hp@4600rpm and 310ft/lb@2400rpm but with the EFI and equal length headers I'd say it was doing a little better than that. Not a racy sports car engine but I gotta tell you it is a vast improvement on the B series, very easy to drive (have still never stalled it once) and has a ton of performance potential. All that's needed to raise the redline a bit is a stiffer set of valve springs, and a step up on the cam can get you into the 6K territory. I wouldn't push the stock pistons much past that but hp should go up accordingly and get you well into the mid or upper 200's. That's good performance for little money.

The weight is a non-issue unless you are racing, but if you feel the ride height needs adjusted upwards these folks may have a spring spacer that will do the job.
[www.suspension.com]

We made 1" spacers for the Roadmaster with the 455 and used Moss 1" lowered competition springs IIRC and that worked out well on a GT that weighs in at about 2700lbs with the BBB, T5, and Jag IRS. Note: due to the 2:1 ratio from tire to spring 1" of ride height = 1/2" of spring height.

Jim

I've started machining a raw forging. This will take a while. Art.

The block has been machined for quite a while now. just haven't been down to pick it up.
Once the resto on the 65 Elan is finished I'll get back to the Rover engine.
Oooops sorry, the lovely Lynne says the boat motor gets built next. Just a normalish 350 sbc ;-) won't take long at all.
Cheers
Fred

Just for info, the top hat liners are made by Westwood cylinder liners. £300 a set here in the UK from Britpart distributors.

My 4.6L block is a later version form 2002. The liners in it sit on a step at the bottom to stop slippage but it's still possible to get a crack behind, although these blocks are supposed to be the most resistant to it. The liners are stock AFAIK but do appear to be either thicker than 'normal' or have some form of top hat on as they measure 101.5mm across the top.

Duncan at Westwood (a very helpful chap) says this is a bit odd as top hats are wider than this and orginal liners are narrower...

Richard, The liners in this thread are GM. Maybe in your case someone put your liners in upside down like mentioned early in this thread?

FWIW , I called Summit today, they say sleeve is .060" wall. Seems too thin ? How about Hylomar at bottom of liner ?
Outdide of sleeve might get wet, in some spots. Onward, Art.



Edited 1 time(s). Last edit at 07/10/2023 10:00PM by ag1234.

A valvetrain revolution is coming. Fred K., do you see it ?
Onward, Art.