7mge inefficiencies

87hilux7mge · 12-22-2010, 11:37 PM

bumping up compression will give you id say about 15-20 hp if lucky, and not at the wheels. u have to get into the 12-12.5 range to see some real gains, and then you stress your entire motor. rings, bearings, valve train. ud wanna look at upgrading rods (not a bad mod neway) and have custom pistons made.

PnP the cylinder head is a fairly easy venture, its just time consuming. i spent 12 hours just on the bowls and short side radiuses. i didnt get crazy on the ports much but cleaned up alot of casting flash and tapered the guides. if you look at flow charts a full "street port" give you a bump in flow from 179cfm@ .30 lift to 201@ .30 lift. mine flowed 198 (+/- 1 cfm on all ports) at .30 and 28". overall i spent about 24-26 hours of straight work on mine, not including valve polishing and lapping. plus i have the stage 2 cams to put in now so those numbers could change.

im hoping to crack the 200 mark with this setup on my GE, b4 i get my sc on there.

bored/honed/decked block (50mm over, .010 removed)
PnP head, resurfaced (.008 removed)
BC stage 2 cams, 268's
adj. cam gears
comp valve springs
NPR pistons, rings (50mm over) balanced (+/- .5 grams)
king main bearings, std size
micro polished crank, std size, balanced (zero balance)
eagle H beam rods, balanced (+/- 1 gram)
ATI super damper
SDS EFI engine management system

mind you this will be in an 87 4x4 pickup with 32" tires.

after the supercharger, depending on pulley, i should be able to hit anywhere from 240-low 300s.

ill post dyno #'s for both n/a and SC form, but it will be a few more months still its done.

BTW, those stroker kits are garbage IMO, i have looked and looked, talked to lots of supra guys, and so far i havent found one thats ran or still running. the 7m motors are stroked 5ms and its pretty well maxed out. lots of custom machining needed. all for maybe 40 hp over stock, so on a proper rebuild, a scant 220-240 if very lucky. thro in the parts that ive invested in, and you might get 260-270, and about 10k spent (stroker is over 3k alone) for something that has the likely hood to fail due to stressed components.

12-22-2010, 11:37 PM	#17
87hilux7mge walbro fp Join Date: Dec 2010 Location: spokane Posts: 479	bumping up compression will give you id say about 15-20 hp if lucky, and not at the wheels. u have to get into the 12-12.5 range to see some real gains, and then you stress your entire motor. rings, bearings, valve train. ud wanna look at upgrading rods (not a bad mod neway) and have custom pistons made. PnP the cylinder head is a fairly easy venture, its just time consuming. i spent 12 hours just on the bowls and short side radiuses. i didnt get crazy on the ports much but cleaned up alot of casting flash and tapered the guides. if you look at flow charts a full "street port" give you a bump in flow from 179cfm@ .30 lift to 201@ .30 lift. mine flowed 198 (+/- 1 cfm on all ports) at .30 and 28". overall i spent about 24-26 hours of straight work on mine, not including valve polishing and lapping. plus i have the stage 2 cams to put in now so those numbers could change. im hoping to crack the 200 mark with this setup on my GE, b4 i get my sc on there. bored/honed/decked block (50mm over, .010 removed) PnP head, resurfaced (.008 removed) BC stage 2 cams, 268's adj. cam gears comp valve springs NPR pistons, rings (50mm over) balanced (+/- .5 grams) king main bearings, std size micro polished crank, std size, balanced (zero balance) eagle H beam rods, balanced (+/- 1 gram) ATI super damper SDS EFI engine management system mind you this will be in an 87 4x4 pickup with 32" tires. after the supercharger, depending on pulley, i should be able to hit anywhere from 240-low 300s. ill post dyno #'s for both n/a and SC form, but it will be a few more months still its done. BTW, those stroker kits are garbage IMO, i have looked and looked, talked to lots of supra guys, and so far i havent found one thats ran or still running. the 7m motors are stroked 5ms and its pretty well maxed out. lots of custom machining needed. all for maybe 40 hp over stock, so on a proper rebuild, a scant 220-240 if very lucky. thro in the parts that ive invested in, and you might get 260-270, and about 10k spent (stroker is over 3k alone) for something that has the likely hood to fail due to stressed components. Last edited by 87hilux7mge; 12-22-2010 at 11:41 PM.