Is downsizing possible?

[Boy from Oz]

In my state in Oz there is a formula that limits the capacity of replacement engines. To fit a 5.7ltr LS1 to my 240Z (73), as planned, the original car must weigh 1175kg (2590lbs). Data I have says a 1970 240Z was 1044-1068kg (2301-2354lbs) but I have nothing for a 73 model. The Nissan plate has left the weight blank.

 

Two request. Does anyone have official Nissan weights for a third month 73 240Z - I suspect they my vary slightly from country to country AND does anyone know if it is possible to destroke and/or reline an LS1 down to 5.2ltr - I think that is about 309cu.

 

What a rule. Seems I cannot use a standard 300hp LS1 but I can install a heavier 600hp 5.0ltr.

[Mike C]

There are two smaller iterations of the motor. One is a 5.3 liter and the other I believe is 4.8. Both found in trucks. A cam swap along with rockers should pump the 5.3 up to close to what the LS1 output is stock. Most truck motors are iron block.

[Boy from Oz]

I have read that Vortec 4800, 5300 and 6000 truck versions of the LS1 were manufactured. It said that the 4.8ltr and 6.0ltr were iron-block only while the 5.3ltr was both aluminium and iron. I will need to find out if any were imported into this country. I just wondered if they were significantly different from a standard 5.7ltr LS1. Does anyone know?

[Mikelly]

I believe the 5.3 liter version is similar in configuration. I know the intake and heads can be swapped onto the LS1 block. This leads me to the statement above. I'm sure there are slight differences, like accessory layout or sensor locations, but I bet everything else is pretty close.

 

Mike

[Pop N Wood]

The good thing is I believe they all use the same bore. So maybe you don't need the whole engine, just the shorter stroke crank and rotating assembly.

[nitro_D]

http://www.conceptcarz.com/vehicle/z8205/Datsun_240Z/default.aspx

 

Couldnt find anything official but this website says a 1973 datsun 240z weighs 2301 lbs | 1043.7 kg.

I'm living in nsw and didn't realise there was such a law.

 

When i do my swap ill be sure to get a 260z.

 

http://www.conceptcarz.com/vehicle/z6298/Datsun_260Z/default.aspx

 

2665 lbs | 1208.8 kg for a 260z. I calcuted that and it means you can fit a max of 355ci engine. So therefore meaning u could use a LS1.

But if you already bought a 240z then you could get a 308 holden engine. There are plenty of them available for under 1.5k$.

Although im not sure what their tunability is like.

 

Good luck!

[Boy from Oz]

Nitro D

 

I have done a bit of research over the last few days.

 

If I can get the RTA to accept that the original weighed 1068kg then I should be able to fit a 5.3ltr LS1. The 5300 has the same stroke but a smaller bore than the 5.7ltr. I know there is a lot of argument about this but the pistons and/or rings were pretty poor on LS1 so I would probably want to redo them before installing a second-hand engine anyway. It just means I will also have to re-sleeve.

 

I am doing a 250 GTO project (must be a 2 seater) and I am very keen to use an all alloy engine as I think it will go with the character of the car. If you are looking for a 260Z there are very few 2-seaters around, nearly all were 2+2s.

[nitro_D]

Im not keen on 2+2's, i dont like how it is stretched after the rear window. Search and i'll find one, theres a few for sale but not many, mainly 2+2's like you said.

 

Does the 5.3ltr your talking about look any different to a normal 5.7ltr ls1? Im talking about just from the top.

[280z-racer]

look for a 5.3L short block and use the LS6 or late LS1 intake and throttle body and and LS1 or LS6 heads. the LS6 cam works in the 5.3 as well.

[Guest 73TPIZ]

Boy from Oz,

 

I think NADA buying guides does a very good job on the car weights. I've compared the NADA listed weights on 5 or 6 cars over the past couple of years to the digital scales we have at work. We use it to weigh tanker trucks when they bring in solvents or take solvent waste. I believe the scales to be pretty dead on as that's how we pay for all our solvents (major parmaceutical plant). NADA's never been more than 50lbs (22ish kgs) off from our scale.

 

Long story short. NADA says 2350lbs for a '73 and our scales said 2380 for my '73 (at least half full of gas). Scales read in 20 lb increments.

 

Here's the link

 

http://www.nadaguides.com/uv/viewresults.aspx?LI=1-12-1-2031-0-0-0&Lnk=1&wSec=12&wPr=1&wPg=2032'>http://www.nadaguides.com/uv/viewresults.aspx?LI=1-12-1-2031-0-0-0&Lnk=1&wSec=12&wPr=1&wPg=2032

 

On the value page, scroll down and you'll see the weight.

 

For any thing else go to http://www.nadaguides.com and click on used cars. It'll say '86 to present but when you get to the body style page you'll see a button for cars older than '86.

 

 

Hope this helps.

 

For comparison it says for a '76 280Z coupe 2588lbs and a 2+2 2748lbs.

 

Take Care,

 

Just noticed it gives the original MSRP for the classic cars. Says my '73 was $4695. Pretty cool.

 

later.

[zgeezer]

You can search this forum for LM7, which is GM's code for the 5.3 L GENIII engine family. You will find threads that discuss some of the differences between engines. Most later truck engines are iron block and aluminum heads and do have different accessory locations and oil pans. There are several LT1 websites that also include trucks. I understand you can downsize the lt1 by using the 4.8 crank and rods. Again, Google is your friend here.

 

g