High Compression 2.6L Astron.

[Superscan811]

Some new toys arrived today...










Bought 4 sets of rods and bearings so I can finally get some of my builds back under way.

The rods weigh in at 635-grams each, a bit lighter than the standard 820-gram rods, and probably a little bit stronger as well..


Cheers.

[A112H]

They are some very sexy connecting rods

[damian]

4 sets

you tripper ;)

[Superscan811]

They are some very sexy connecting rods

I Like too.

There was no way to lighten a set of standard rods down anywhere near this weight and still have them reliably spinning over 7500rpm.

4 sets

you tripper ;)

Have 4 engines to build and since the VR4 setup sold, may as well bulk buy the rods and save a bit of money. Compared to buying the sets individually, saved over $70 per set.

While there is still a lot of work to be done, I now have all the major components for the 4 engines, just need a little time to be able to assemble them.


Cheers.

[Superscan811]

Some new kit I purchased this week.

41.5mm Flat Slide carbs.







They aren't the "constant velocity" style carbies but they will have better throttle response with the correct foot work.

These require a bit of finesse to get the best performance out of them, but I'm more than willing to experiment..

I'll bore them out to 42mm to match the inlet ports and also extend the runners to improve the low down torque (and also to keep Cheaterparts happy ).

These should work VERY nicely on one of my high comp N/A engines...

These carbies have pump jets so I expect there will be a reasonable amount of work involved in tuning them correctly.
From the last picture you should be able to see these are designed for "MOTORCYCLE RACE USE ONLY"



Cheers.

[Superscan811]

After the block for the HC engine was acid dipped, which I thought was supposed to remove oil, grease and rust, it was bored, honed and decked, but when I went to replace the old welch plugs, the water jackets were completely choked with rust...

I now have the block soaking in a molasses/water mix to remove the rust from the water jackets. It should take 2-3 weeks to fully remove the crud I couldn't get to.

I was digging pieces out like this.


And these next 2 pictures shows how much crud was in there.






Molasses is only supposed to eat the rust, nothing else, where as other types of chemical treatments would damage the work done. Guess I'll find out in a few weeks if that is true.



Cheers.

[geezer101]

Molasses is only supposed to eat the rust, nothing else, where as other types of chemical treatments would damage the work done. Guess I'll find out in a few weeks if that is true.

My relatives who were into restoring 1930's/40's Fords used molasses to eat the rust from various parts before painting them. It worked well but it was a waiting game for it to do it's thing. Maybe your bare block should've been hot tanked or even something a bit more basic like blasting out the galleries with a high pressure cleaner. IMO You'll still need to do it after the molasses bath to shift any heavy sediments left behind. Are your new carbies 'mechanical lift'? If so, I've been told you can expect a difference in throttle response over the CV's (apparently a BIG difference )

[Superscan811]

My relatives who were into restoring 1930's/40's Fords used molasses to eat the rust from various parts before painting them. It worked well but it was a waiting game for it to do it's thing.

I've been told 2-3 weeks should remove the rust.

Maybe your bare block should've been hot tanked or even something a bit more basic like blasting out the galleries with a high pressure cleaner. IMO You'll still need to do it after the molasses bath to shift any heavy sediments left behind.

The block was supposedly hot tanked then acid dipped before the work was done. Hmmm....

Are your new carbies 'mechanical lift'? If so, I've been told you can expect a difference in throttle response over the CV's (apparently a BIG difference )

Yes the slides are shaft operated, not vacuum. I have also been informed that the FCR's should give better throttle response IF you use the throttle correctly. That is where the CV carbs are good, just put your foot to the floor when ever you want to go....


Cheers.

[GB_BB4C]

After the block for the HC engine was acid dipped, which I thought was supposed to remove oil, grease and rust, it was bored, honed and decked, but when I went to replace the old welch plugs, the water jackets were completely choked with rust...

were the welch plugs not removed prior to it being acid dipped/hot tanked. if not, why not. this is most likely ya problem.

[Superscan811]

were the welch plugs not removed prior to it being acid dipped/hot tanked. if not, why not. this is most likely ya problem.

No they weren't, but still,it should have removed some of it...

Anyway, I removed the block today, washed it down, and it's come up excellent, almost like new. Had to spray it with protective oil because as soon as I washed it down, it started with the surface rust.


Amazing difference.

Cheers.

[Superscan811]

Due to the Triton head incident last week, work has progressed on the High Comp engine.

Pistons and rods.




Lightened crank and pistons/rods installed (Bottom End)




Piston height at TDC


Compression ratio should be around 14:1 using a M7 Magna head.


Waiting on these valves to arrive:

51mm Inlet valves

40.5mm Exhaust Valves

Should be interesting..




Cheers.

[A112H]

Me likey

[75wagon]

14:1?

[Superscan811]

14:1?

If I just bolt on a STANDARD M7 head, it would be 16:1.

With all the work I'll be doing to the head, removing sharp edges in the combustion chamber, de-shrouding the valves,etc.. it will be closer to 14:1.

The larger valves and seats will be recessed an extra 1.5mm to make room and to ensure the valves don't hit the piston or each other.

As the stems will have to be shortened anyway, it won't be a major issue.

I've thrown the gauntlet down to Cheater to get his track hack up and running, so hopefully I'll have a bit of competition.

The Triton will be a good "test bed" for this engine because it weighs around 1500kg's and if all goes well, I may build my turbo engine next, just for a bit more fun.




Cheers.

[cheaterparts]

I've thrown the gauntlet down to Cheater to get his track hack up and running, so hopefully I'll have a bit of competition.

may be when I get time do you think I'll need 3 or 4 plug leads to keep up

[Superscan811]

I've thrown the gauntlet down to Cheater to get his track hack up and running, so hopefully I'll have a bit of competition.

may be when I get time do you think I'll need 3 or 4 plug leads to keep up

Probably only 2 extra because you can build a decent engine..

[geezer101]

I ran into this a while back - http://www.google.com.au/url?sa=i&sourc ... 7167456996 What do you think? The adapter plates can be supplied as blanks and then made to fit. A good solution for cold air induction and will tame the induction noise too (could be a good or bad thing depending on your POV)

[yno26galant]

would like to see what sort of power the high compression engine will push out

[Superscan811]

I ran into this a while back - http://www.google.com.au/url?sa=i&sourc ... 7167456996 What do you think? The adapter plates can be supplied as blanks and then made to fit. A good solution for cold air induction and will tame the induction noise too (could be a good or bad thing depending on your POV)

It's a good idea but i'd prefer a bit more area between the end of the trumpets and the manifold. Have already bought a stack of 100mm aluminum pipe, to make my own plenum/cold air induction/water injection setup.

would like to see what sort of power the high compression engine will push out

Me too..



Some more bits arrived today


The exhaust is only 2.5mm larger than standard



but the inlets are 5mm larger than standard.



The 2 M7 heads have had the VW valve seats installed so a bit of porting is now required



This is my M8 head with 1mm OS valves in it


Same head with the SBC valves placed there


The clearance, in between the valves will be a lot larger when the seats are cut 1.5-2mm deeper than standard. The other benefit is the pistons may not have to be flycut, hopefully...


Cheers.

[Billsy]

looking on with interest, I havent seen someone attempt to put in valves of this size on an astron before.

[Superscan811]

looking on with interest, I havent seen someone attempt to put in valves of this size on an astron before.

For a better impression on how the valves fit.


It looks like there will be around 4mm clearance inbetween the valves.
While the inlet is sitting flush in this pic, the M8 head has had 2.5mm shavesd off it AND the valves aren't properly seated, so they should end up sitting around 3-4mm lower in the other heads I'm preparing.


This all bodes well for no further machining required for the pistons.



Cheers.

[Tj.]

14:1?

You're going to need another motor just to crank the bloody thing over!
Impressive work

[Old Colt]

Nice build here.
Many years ago I was building a head with the 2.02" intake valves and 1.6 exhausts. The way I approached mine was to move the valve seat outwards to maintain clearance between valves.
This was done by making tooling that fit on the rocker shaft to guide a reamer for offset boring the guide hole, Then cutting the new seat location.
This provided good valve action and the port flow was phenomenal.
Unfortunately I struck water with further straightening an intake port and never completed the head to running status.

[Superscan811]

Nice build here.

Thanks.
I figured that I wasn't the "trailblazer" in this area, but with the modern M6-M9 heads, there seems to be little information/development.

Unfortunately I struck water with further straightening an intake port and never completed the head to running status.

With the help of Cheaterparts, the later heads seem to have a bit more "meat" to remove before hitting the water ports.
One thing I've been wanting to try is raising the port height by 20mm. This, in theory, should dramatically improve the Volumetric Efficiently of the head by around 15-20% at higher RPM's. The only down side would be increased inversion below 3000rpm. Not a problem for a race engine, but for a street-able car, it may be a bit of an issue.

My "idea" was to bore a 60mm hole and then put in an offset sleeve. This would allow for the water galleys to function and the inlet port to be successfully raised..
The main issue I've come across is actually the valve spring base.

A bit more R&D (and time) is required before this can happen.


Cheers.

[Old Colt]

The area I hit water was on the front of the port as I was straightening it. I was finding on the flow bench that evening up the port each side of the guide boss worked wonders for flow.
With old iron British heads we used to bore into the heads at an angle and braze in a tube providing much improvement.
A simple but crude down draft porting. Not sure just what the port flows were like but we did have a Stuska dyno to measure with and saw great results. Everything was so simple back then.
I would expect for your desired goal in the port experiment would be to raise the roof a bunch at the gasket face but not much at the guide. Insert a stuffer to raise the floor as needed but not to raise the throat all that much so you do not overly shorten the guide or have a spring drop through. If I were doing this I would want to bring the ports forward to straighten them and get the swirl out of the chamber and let the charge tumble.
Every time I look at a 12V 6G72 head I wish the G54 had those ports.

Now for something totally different and since you are not afraid of big projects you should get your hands on a BMW s14 M3 head. This head is not far from being a bolt on to get a DOHC 4 valve engine.
I have a head bolted to the G54 but other projects keep me from finishing it.

[Billsy]

Now for something totally different and since you are not afraid of big projects you should get your hands on a BMW s14 M3 head. This head is not far from being a bolt on to get a DOHC 4 valve engine.
I have a head bolted to the G54 but other projects keep me from finishing it.

Now this im sure will get some attention if it can be done successfully.

although these heads would be expensive and few and far between here in aus.

[RaptorReed]

Well...http://classiccolt.forumcircle.com/view ... mw&start=0, might have to register to see thread, but that shows how far Charlie got with the idea .

[A112H]

Well done Tim, I was searching the interweb for that bloody page, could not remember where it was, lol

[Old Colt]

I guess I should get some inspiration and move forward with this swap but I need to finish the 4G92 Mivec swap first.

[Cottees]

Even though S14 talk is a little off topic, I will share this though. This is a quick comparison of a S14 and 4G54 head gaskets. 4G54 being red, S14 being blue.