'original' small block vs LS7 dimensions?
Discussion
OK, just at the plotting stages right now, and it might get no further.....but 7000rpm and losing a few Kg up front is mighty tempting 
I'm just wondering if an LS7 would 'fit' where the small block currently lives? It is real tight in there. I could be up for a 'quick and easy swap', but I don't need the hastle of more chassis or body mods. I can work out I'd need to change the headers, put on a high pressure fuel pump, find somewhere for a dry sump tank etc., and I see you can get 'conversion' mounts that should mean it would drop onto the existing SBC mounts. I also understand that the back of the block is the same, so I can re-use the bellhoising. Is it the same at the rear of the crank to re-use the ring gear/clutch too?
Biggest problem would be clearance; it looks like the LS7 is bigger externally than the SBC, and I've a couple of areas where it's real tight.
First is at the back of the block - the top outside edges of the 'V'. I've no extra clearance there at all really - it's OK if the heads are a bit bigger, it's the outside edge of the block at the rear that is real close to a chassis tube. Anyone know what the width is from widest edge to edge on the block, ignoring the heads? And if it was sitting on SBC mounts, is the top of the block at the same level?
Next, it's pretty tight at the front. I've just a harmonic balancer and a dual row pulley, but I can't get the motor in/out the car without taking off the pulley. I gather the LS7 has an oil pump at the front so does that make the nose 'longer'?
Finally I've the clearance below the motor. I'm OK at the rear of the motor, but clearance at the front is limited. The chassis was really modified around a Canton winged sump - so plenty space where the sump bit goes, but there's not too much ahead of the 'sump' part. If the LS7 is dry sumped, does that mean the whole sump is smaller (like the 'unsumped' part of the Canton pan), or is it deeper than the 'unsumped' part?
I guess what I'm saying is if I dropped an LS7 on the existing SBC mounts, where would I find it wider, longer, taller?
I'm just wondering if an LS7 would 'fit' where the small block currently lives? It is real tight in there. I could be up for a 'quick and easy swap', but I don't need the hastle of more chassis or body mods. I can work out I'd need to change the headers, put on a high pressure fuel pump, find somewhere for a dry sump tank etc., and I see you can get 'conversion' mounts that should mean it would drop onto the existing SBC mounts. I also understand that the back of the block is the same, so I can re-use the bellhoising. Is it the same at the rear of the crank to re-use the ring gear/clutch too?
Biggest problem would be clearance; it looks like the LS7 is bigger externally than the SBC, and I've a couple of areas where it's real tight.
First is at the back of the block - the top outside edges of the 'V'. I've no extra clearance there at all really - it's OK if the heads are a bit bigger, it's the outside edge of the block at the rear that is real close to a chassis tube. Anyone know what the width is from widest edge to edge on the block, ignoring the heads? And if it was sitting on SBC mounts, is the top of the block at the same level?
Next, it's pretty tight at the front. I've just a harmonic balancer and a dual row pulley, but I can't get the motor in/out the car without taking off the pulley. I gather the LS7 has an oil pump at the front so does that make the nose 'longer'?
Finally I've the clearance below the motor. I'm OK at the rear of the motor, but clearance at the front is limited. The chassis was really modified around a Canton winged sump - so plenty space where the sump bit goes, but there's not too much ahead of the 'sump' part. If the LS7 is dry sumped, does that mean the whole sump is smaller (like the 'unsumped' part of the Canton pan), or is it deeper than the 'unsumped' part?
I guess what I'm saying is if I dropped an LS7 on the existing SBC mounts, where would I find it wider, longer, taller?
Ls7 is appx 17.25" across the block where the head sits on the block. Oil pump etc is all integral to the front cover. The cover itself is appx 7cms deep and then you have to add on the pully width/depth. As for the ls7 sump it's 12 cms deep at the rear where it mates with the bellhousing which is different to sbc bellhousing. That said you could use the sbc housing but I'd use the correct item. The sump is 5 cms deep at the forward end.
As for the clutch and flywheel, they're bigger diameter on the ls7. It is possible to use an 8" clutch and much smaller flywheel for racing applications which would probably get around the top rail issues. HTH.
Boosted.
As for the clutch and flywheel, they're bigger diameter on the ls7. It is possible to use an 8" clutch and much smaller flywheel for racing applications which would probably get around the top rail issues. HTH.
Boosted.
Have a look at this page
http://paceperformance.com/index.asp?PageAction=Cu...
The LS1/Vortec engine they have on that page is not completely like an LS7 as that wheel is is not there, the sump is less than half the depth and the LS7 intake is the same height roughly as the valve covers (the truck intake is massive)
http://paceperformance.com/index.asp?PageAction=Cu...
The LS1/Vortec engine they have on that page is not completely like an LS7 as that wheel is is not there, the sump is less than half the depth and the LS7 intake is the same height roughly as the valve covers (the truck intake is massive)
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