6.3 chevy-engined monster

griffman said:

Mr Noisy,

20k would of course buy me a nice car already built but it wouldn't be the same.

I just want you to know I haven't posted the thread to gloat or make anyone envious, but because I hope as fellow V8 Landie men you would appreciate the thought and hard work that has gone into the project.

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griffman said:

Mr Dirty

I looked at all options - this engine would munch an R380 - the Ashcroft uprated LT85 is agricultural but much stronger and with an AP Racing clutch would have been ok - this is what my mate has bought to mate up to my old TVR engine which he now has in his 90 - it is much fun!!!!!1

However the whole point for me was to build a civilised hot rod/ cruiser
that would look cool, sound fantastic and be very fast.

I had a long chat with Dave Ashcroft about my options and we came up with the solution I now have.

It is a ZF HP22 with uprated heavy duty Internals, uprated sprag clutches and govenor/pump (Stage 1) and the front end from a HP24 which is much stronger than the 22 front end - this is a stage 2.

We then went for the biggest torque convertor available - Ashcrofrt supply an adaptor for the big rover (5.0 plus engines), but not for the Chevy.

I had the old Overfinch adaptor from the original auto setup which was basically just a slightly thicker flexplate with a boss assembly - this was the standard overfinch application and can only be used with the medium torque convertor - most of the torque was wasted and lock-up was painfully slow in coming.

The guy who built my engine is a Santa Pod Mechanical legend and he came up with a design that is very similar to the system he builds for Chevy dragsters (but not as hardcore) in that is it uses a lightweight ring bolted to the torque convertor, and then a semi-flexible plate bolts to this and then this in turn bolts to the boss which is in turn bolted to the flywheel.

The principle is that no one area is taking all the torque at once and everything gives a little, so spreading the load across the friction system.

He has had no failures with this system.

In practice it works very well - there is a little reluctance to change up from very cold but after the first up-change it is superb - the changes are virtually imperceptible and lock-up is virtually instantaneous.

Dave Ashcroft told me the damage to gearboxes really occcurs on full-throttle kickdown but I have so much torque I have set the kickdown to the minimum sensitivity - I don't really need it and changing down to third manually to overtake is no chore in any case.

As I said earlier in the thread the whole thing runs like a dream and this engine/gearbox did 2000 miles in the disco before the defender rebuild started.

The only subsequent addition is a new late-type(post 97) 1.2 transfer box from Ashcroft as they have taper bearings and the input bearing is cross-drilled to prevent wear - they supply the correct gearbox output shaft with the transfer box.

This later item doesn't whine after 10000 miles like the earlier ones.

Thanks for your interest.

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dirtydiscov8 said:

what goes on inside an autobox is pure witchcraft!

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Mr Noisy said:

Absolutely mate, I am the first person to encourage custom work rather than buying something off the shelf, and I apologise if I came across wrong, i wasn't accusing you of gloating or anything! Earlier in the thread i thanked you for posting!!

So lets keep it up!!

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Mr Noisy said:

Absolutely mate, I am the first person to encourage custom work rather than buying something off the shelf, and I apologise if I came across wrong, i wasn't accusing you of gloating or anything! Earlier in the thread i thanked you for posting!!

So lets keep it up!!

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zen said:

hi again..

wondering why you not gone with ashcrofts electronic shifter sytem..i quite like the idea of sequential semi auto/manual..if i decide to go auto ever thats what i will be using i thinks.

re lt85..i is on number 3 now..ashcroft made this one in car.its uprated..its done 10000 and is dying pretty quickly..i give it 5000 max before it explodes again...pooh..5th gear..have completly ripped it off the previous one!
gave up on lt95's..no one can build them so they dont sound like a jet plane,and besides the center diffs keep popping..
i may go jap gearbox and make a converter to lt230..atleast it wont blow up!

oh and jap v's can sound good..its all in the exhaust..(or lack of)

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dirtydiscov8 said:

Might be worth the £45 to upgrade the diff pins in the transfer box with the ashcroft one piece item. The standard diff pins don't look man enough to handle 3.9 power/torque levels let alone what your's will be putting out.

Come on don't tell me your not going to be kicking down a gear and watching the nose rise - an autobox is pure witchcraft!

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Dr_evil said:

Pics and a vid of the Chevy

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bigwilly said:

Zen, Slightly off subject but have you done a build thread - cant find it anywhere?

Hope you get loads done today griffman! DONT forget the pics!!! Im hopefully gettiing mine on the road this evening after its swimming lesson on the 27th Dec

As Zen said, will be great to see it when its done - perhaps we should sort a forum meet out somewhere?

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griffman said:

pics are earlier in thread - no video as yet - that will wait for the first run after MOT!

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Dr_evil said:

I meant the old chevy not this hybrid

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