Tear Down and Reassemble Unstarted 1.7 built to 2270, 1.7 to 2270 Unstarted 10 Year Old Build Options

[Robroe]

Moved from topic of first start of 10 year old build to tear down, inspect and reassemble. The 10 year old build is from a 73 1.7 to a 2270. Stroked to 78 mm and 96 mm cylinder diameter. Heads are Ham/RAT with 36 mm exhaust and 44 mm intake. Both are nicely ported.

Have torn it down to the case and checking crank end play before I split the case and pull the cam and crank. So far, everything is new and looks in good order. I'm concerned about oil passages being blocked with old assembly lube so a complete tear down and reassemble is happening. Discovered stacked cylinder spacers (4) totaling .150". So looking to replace those with single spacers. So far I can only find .160" spacers from type 4 store and may just use them as impact on compression appears minimal. Was shocked to discover crank end play is .450"! Sure glad I didn't try to start this thing. Will check again in the morning to make sure I'm checking it correctly, but I'm doing the same thing on the videos such as Ian Carrs YouTube engine builds so pretty sure I'm checking it correctly. Now to figure out what to do about that huge end play.

Any thoughts about what to watch out for?

[Jack Standz]

From pictures I’m don’t think I see the Raby Rear Main Seal drain back modification . I’d do that while case is split.

Can you point me to Rabys Rear Main Seal drain back modification? Tried searching but haven’t found anything except reference to it, not what it is or how to do it. Thanks!

Yes, I was thinking about this question and came back to ask. But you beat me to it.

Some of us are visual people. Anyone have a photo of this modification they could share? Maybe with some measurements too? The video isn't easy to see things. Maybe a better screen would help, but a few good photos are better.

I looked at Bob Burton's friend's rebuild. But, it seems his was built before this modification was being used at RAT. We have a motor we're planning & rather than take a guess at how to make this modification, it'd be really helpful to see how others have done it.

On a related point, does anyone have photos of a roller cammed Type IV? We have Type 1 tool steel lifters that we plan to use with modified lifter bores on the next motor build. However, the roller cam has benefits over solid cams. Any help with getting a roller lifter/cam setup that you could share would really help the 914 community.

Thx

I was going down this road as well...

I'm a full roller, VVT, 4 valve, DI, variable intake, DOHC, VATN turbo with two stage intercooler type of guy.

When you just say "Fuch it" and drop the WHOLE Type 4 idea EVERYTHING gets so much easier...

And a SHITLOAD cheaper!

The only way I'll build a Type4 is if I luck into exactly what the OP has.

That's what has made this thread interesting for me.

Be careful with saying rollers are better.
They are different.
Up to 230@.050 flats are usually FASTER at opening the valves off of the seats.
Rollers open slowly...
Rollers can run steeper ramps and are better for large lift/duration but anything below those numbers the flats will work better.

The cost of creating roller lifters for a type 4 vastly exceeds the value they will provide the engine IMO.

How much MORE power do you think they will make?
10% would be a shitload IMO.
So, 20-30 HP for how much money?

Raby bought up ALL of the oversize ceramic lifter stock on the market.
I think he's big into ceramics now.

He mentioned rollers at one time on one of his pages.
8K was the cost...

I can buy 2 used Bentley W12 twin turbo motors with all of the garbage on them for that type of money.

I can buy a 4-mile LGX GM V6 for 3K if I want.
Used ones can be had for 1K.

I actually want one of those...
(IMG:style_emoticons/default/devil.gif)

Yeah, I'm with you. If we were going with a water pumper in a 914, I'd seriously think about a quad cam 32 valve 928 motor (actually have one in the garage) or a Cayenne V8. Kinda like the alien. Because, why not? But, we aren't going that route. We like air-cooled.

Just like the idea of a roller cammed Type IV motor. Didn't say it was better, but it does have benefits. Less friction, lower spring pressure while potentially higher rpms before valve float, potentially better spring control (maybe run behive springs), faster more aggressive ramps on the lobes (getting custom cams and all the development over multiple iterations needed is really the area likely to kill the dream), etc.

Wasn't thinking you'd have to create roller lifters for a Type IV. Just find existing ones (Ford?) and make the lifter bores & bosses work with them. Probably solid roller lifters, but maybe hydraulic would work. Benefit is no valve adjustments. Again, you get back to developing a custom cam that works. That would be expensive and time consuming.