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#17332 12/02/07 07:29 PM
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Hi Guys,

I've got a 292 that i want to rebuild en give some extra power.

This engine is manufactured in mexico. Are these blocks and heads good to use, or are the not worthy for a good rebuild.

I want to build a street 292 with high compression, and lots of torque. It is not going to be an high RPM machine.

castings:
block 93406004
head: 93400104

Does anybody know how much CC the head is orginal and how much CC with 0.060 milled of a head, like the clifford heads they are selling?

Greetings Marcel.

#17333 12/02/07 07:57 PM
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The blocks could???? be a touch stronger due to the added web casting you see on them blocks.But i personaly do not know. As to the CC's on the head could be 72-74 CC's
with a flat top piston and the 72CC'scould give you around the 10-1 compression mark. What compressiong are you looking to have?? I can crunch the numbers for you and, Tell you what you will need CC wise to get that compression.


Larry/Twisted6
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#17334 12/03/07 08:57 AM
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I am running a 86 Mexico engine in a pulling tractor. It came out of a UPS truck. I am sure it had plenty of miles on it when I got it. It had very little wear in the cylinders and only had to have the mains turned .010. The rods are still stock. The engine runs all out when it does run. I am pleased with it.

#17335 12/03/07 02:04 PM
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We built one as a hot street/strip motor and started out at 60 over. After running it about a year the bores were oval towards the drivers side. It may have been just a bad block, but replaced it with an earlier US version and no problem.


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#17336 12/03/07 04:25 PM
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Chucky Offline OP
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As to the CC's on the head could be 72-74 CC's
with a flat top piston and the 72CC'scould give you around the 10-1 compression mark. What compressiong are you looking to have?? I can crunch the numbers for you and, Tell you what you will need CC wise to get that compression.

Larry,

A little help would be appreciated. I've read Leo's book like 6 times and i've been reading a lot on the board. But i find it a little bit difficult to choose a right engine combo, with the right parts for a good and reliable engine .

It's for my 82' Chevrolet Van, street use - work engine, idle to max 5500 rpm.
Behind the engine i'm putting a TH700R4 for some better mileage and performance.

I want to run on the "save" side of the CR with RON 98 fuel, that's the same as your 93 premium fuel. I don't know if its possible to run 10-1.
Most of the time it wil ran on LPG (for economical reasons), but if necessary i want to run on RON98.

I was thinking to buy custom build pistons (flat tops), and deck the block for a nice/good gasket surface and square it with the crankshaft centerline.
- RV/towing cam, i still don't know which one.
- offy intake and a 390 holley carb.
- landons cast iron headers (for the sound!! i know it doesn't do much for the power on low rpm).
- Clifford head with the 1.94 intake and 1.60 exhaust valves, milled 0.060
- rebuild rods from clifford.

What do you think?? Am i in the right direction :rolleyes:

Greetings

#17337 12/03/07 07:04 PM
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Well I honestly can't say anything good about the head work clifford does from what i have seen.And
Personaly I think you will be happier with a 9/9.5-1 on the compression and a head with the samller 1.8 & 1.6 valving. for a Good street head.
And a cam like this I think would be a good with
the 9/9.5-1 compression with the Offey and a 390
Or so Cfms.Cam duration at the seat in/ex 262/272 112 lobe seperation 505/530 lift 207/217 @.050 idle to 5000 rpms.this one has a good idle.But it gives you something to look at.And i'd only take enough off the block Deck to make sure it is true.
The .060 off the head is fine.


Larry/Twisted6
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#17338 12/03/07 07:20 PM
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thanx.

And how i am going to make 9/9.5-1 CR?

if i use flat tops and a 72cc head i have 11-1 CR (desktop dyno calculator)

and what if i use a milled head 0.060??

And why the 1.80 intake valves?? isn't a bigger valve better for breathing?

And what about lump porting the head or is it not useful to do?

#17339 12/03/07 11:12 PM
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With a lump ported head all Valve sizes will gain CFMs. But personaly if your looking to keep some
mpgs I feel that the 1.8 is more then enough for street use Or even for a Hot street set-up.
And you do not need to Unshroud the valve as much,
as you would need to do with a 1.94. By having
the valve unshrouded The will help the flow around the Valve and also add to the CCs on the
head.(unless you remill to keep the same CCs)You
can also go with a shallow dish to get the compression your after.
When you used your desk top calculator did you also take in account the gasket thickness and,
How much the piston is down in the Bore? Or did
you go with a Zero deck?? again Personaly I would
not Zero deck a Street Block. Reason being is if
You ever blow a gasket and It ends up Burning a groove in the Block and Not just the Head. You would end up having to Find New pistons.
Because Now if the Block needed to be Milled to fix it the pistons would be sitting Outside the Deck surface. (Not a good thing dollor wise.)


Larry/Twisted6
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#17340 12/04/07 12:43 AM
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You can always mill or turn the pistons down a few thou to get the deck height where you want it if you did groove a slot on the deck.
No need for new pistons.

I am telling you guys,if you get zero or close to zero deck,you will be able to run higher compression.
It's all about having a good or proper quench.

Not sure if I ever saw a street 6 cylinder engine get a groove in the deck from blowing a head gasket & I have blown a few with nitrous & did not have any grooves any of those times.

I suppose you can get a groove if you continue to drive it w/a blown head gasket?

MBHD


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#17341 12/04/07 09:18 AM
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Your right hank about the groove in the block I have seen two blocks get it.BUT normaly the head takes the beating.And yes the pistons could be milled depending on The piston.( a pop-up not so easy to remill) But also if a head gasket issue is found in time about the only thing then that gets hurt is your pocket & time to fix it.lol


Larry/Twisted6
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#17342 12/05/07 04:06 PM
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Chucky Offline OP
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Hi Guys,

about the CR calculation:
The compressed head gasket thikness i used was 0.040" and a zero decked block.

I thought that it was better to zero deck te block for the swirling effect/quench area etc. But not just by milling the "flesh" of the block, but using custom made pistons with a larger compression height. So i "save" the block for a later rebuild (milling) if necessary ;\)

Is it possible make a custom "dished" piston??

I'm sorry lot of questions everything is new for me \:\)

Greets.


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