Gordo
19-07-2005, 04:02 PM
Intro
I thought a thread was needed in the fab section for those that have started/finished their trek down the road to Jeep I6 Stroker Nirvana.
I've just taken a few baby steps but thought I would share with others who are keen to follow the path to stroker enlightenment also.
The desire for a stroker was to get some more HP out of the 4.0L and a LOT more torque whilst not requiring any engineering or and running on ULP fuel. The should aid short sprints in winch comps and the extra torque will make general offroad crawling easier.
Risks involved are the increased grunt will chew through drivetrain components more easily and will make fuel economy an even DIRTIER word under heavy right foot. For normal onroad driving without extra right boot economy is expected (hoped) to be same or better than stock.
Rear wheel Dyno figures will be obtained before and after the stroker is installed.
Only current engine mods are 2.5" exhaust + extractors, TB spacer, Reusuable Pod filter on snorkel.
Project budget : $2500
*plenty* of labour costs will be saved by using forced labour (conned mates lured by the promise of free beer and pizza) to remove motor, tear down, port block, install engine internals, reassemble and reinstall motor in the Jeep.
Donor vehicle
The Goatsack - 1997 TJ Wrangler (4.0L 6 cyl)
The spec :
4.7 stroker as per Dino Savva's stroker bible :
http://www.jeep4.0performance.4mg.com/stroker.html
http://www.angelfire.com/my/fan/stroker.html
4.7L medium-buck stroker
Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom +0.060" bore pistons with 1.38" pin height & 25cc dish
9.6:1 CR
Crane #753905 204/216 degree camshaft
Ported big valve 2.02"/1.60" cylinder head
Mopar Performance 0.043" head gasket
0.043" quench height
Flometrics F&B 68mm billet TB
Accel 26lb/hr injectors with stock 49psi FPR
270hp @ 4800rpm, 335lbft @ 3400rpm
or in newspeak...
201KW @ 4800rpm, 454nm @ 3400rpm
Improvement over stock :
130kw (193hp) @ 4800 rpm -> 201 kw = +71kw
305nm (225lbft) @ 3300 rpm-> 454 nm = +149nm
or to compare..
Chev LS1 5.7L V8 (in current V8 Commodores) ;
220 kW @ 5000 RPM & 446 Nm @ 4400 RPM
Jeep 4.7L stroker :
201KW @ 4800rpm & 454nm @ 3400rpm
Clifford performance was right.... 6 DOES = 8 :) :) :) :) :)
The parts to date :
Parts amassed and approx landed costs in AUD$ to date :
1x 4.0L working block 130k of light use ;) (labour : 0.060" bore, acid dip, new welsh plugs, gaskets, etc)
http://www.angelfire.com/my/fan/BLOCK1.jpg
6x 4.0L rods retained (labour:to be shotpeened and balanced)
http://www.angelfire.com/my/fan/258_rods.jpg
1x 4.0L head (labour: get bigger valve seats to accept new valves and port job and general cleanup, de-burr, etc)
http://www.jeep4.0performance.4mg.com/images/ph1.jpg
1x 258 (4.2L) crank ("heavy" crank ie Jeep not AMC Eagle) from 1979 CJ7. labour: To have snout shortened 10mm to 4.0L length, needs to be balanced.
http://www.angelfire.com/my/fan/Crank_kit.jpg
8x Accel 26lb injectors (2nd hand off US ebay - $200) off a Camaro. labour: cleaning prior to use. 2x as working spares. Are a Bosch type II design. For 4.5/4.6 strokers using 258 rods more common 24 lb models from Fords and Chevs can be used.
http://www.aussiejeepimages.com/gallery2/d/29424-2/26lbinjectors.bmp
16x 2.02/1.60 ss valves & colletts (new off US ebay from engbldr - great service ! $134). use 12x in motor use other 4x for paperweights.
http://www.aussiejeepimages.com/gallery2/d/29427-2/202valves.bmp
1x Crane hydraulic cam part no (#753905 204/216 degree, from Summitracing.com - $200)
http://static.summitracing.com/global/images/prod/norm/crn-753905_m.jpg
1x Mopar 0.043" head gasket #P4529242 (from wyckoffchrysler.com, $80).NB stock is 0.051"
Parts to get
6x Ross forged custom pistons and rings ( www.rosspistons.com, $1000) specs : rod length : 6.125, bore size : 3.935, stroke : 3.895, head cc : 56.7, block height : 9.453
http://www.angelfire.com/my/fan/677P_pistons.jpg
12x hydraulic tappets (ebay, $40)
1x kit engine bearings (source locally - cam, crank, etc - $40)
1x adjustable MAP sensor mod ($15 is parts as per gojeep's site)
http://go.jeep-xj.info/MAP%20024.jpg
1x 62mm bored stock Throttle body (TB). As per gojeep's site. Got the flap wheels just gotta get into it ! Will save $$ on a billet 68mm one.
Considerations
May require a custom ECU (eg Wolf 3D). No mention found during research as a requirment but may be desirable to get a happier running stroker motor. Hopefully the adjustable MAP sensor with be sufficient for the early stages.
May also require hi-vol oil pump if stock one can't cope. Should be ok as very little hi-rpm (+5500) work forseen. Same reason for reusing the stock valve springs and retainers.
Possibly get a baffle welded into stock sump to avoid lost HP from splash. May require larger vol sump if cooling bnecomes an issue.
Possible require bigger radiator if cooling still an issue (Aussie desert cooler 3 flow unit $400).
Will be hitting an old 265 and a 245 Valiant crank at home with the vernier soon to see if either can be used in leu of the 258 one. Long shot that it will fit but it would push capacity up somewhere near 5.0L. Compression may become too high >9.7:1 and would require a thicker head gasket and different pistons and would also be unchartered ground. Nothings impossible though ! But the end result must still run on ULP and be within the budget.
Pics to come as the work begins. (as well as ones pilfered from Dino and GoJeep's sites amongst others)
Resources
Dino's great sites as above +
yahoo Stroker group : strokers@yahoogroups.com
Rockcrawler writeup by Tony Lopez : http://www.rockcrawler.com/techreports/stroker40/index.asp
I look forward to reading info on others stroker projects too :)
I thought a thread was needed in the fab section for those that have started/finished their trek down the road to Jeep I6 Stroker Nirvana.
I've just taken a few baby steps but thought I would share with others who are keen to follow the path to stroker enlightenment also.
The desire for a stroker was to get some more HP out of the 4.0L and a LOT more torque whilst not requiring any engineering or and running on ULP fuel. The should aid short sprints in winch comps and the extra torque will make general offroad crawling easier.
Risks involved are the increased grunt will chew through drivetrain components more easily and will make fuel economy an even DIRTIER word under heavy right foot. For normal onroad driving without extra right boot economy is expected (hoped) to be same or better than stock.
Rear wheel Dyno figures will be obtained before and after the stroker is installed.
Only current engine mods are 2.5" exhaust + extractors, TB spacer, Reusuable Pod filter on snorkel.
Project budget : $2500
*plenty* of labour costs will be saved by using forced labour (conned mates lured by the promise of free beer and pizza) to remove motor, tear down, port block, install engine internals, reassemble and reinstall motor in the Jeep.
Donor vehicle
The Goatsack - 1997 TJ Wrangler (4.0L 6 cyl)
The spec :
4.7 stroker as per Dino Savva's stroker bible :
http://www.jeep4.0performance.4mg.com/stroker.html
http://www.angelfire.com/my/fan/stroker.html
4.7L medium-buck stroker
Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom +0.060" bore pistons with 1.38" pin height & 25cc dish
9.6:1 CR
Crane #753905 204/216 degree camshaft
Ported big valve 2.02"/1.60" cylinder head
Mopar Performance 0.043" head gasket
0.043" quench height
Flometrics F&B 68mm billet TB
Accel 26lb/hr injectors with stock 49psi FPR
270hp @ 4800rpm, 335lbft @ 3400rpm
or in newspeak...
201KW @ 4800rpm, 454nm @ 3400rpm
Improvement over stock :
130kw (193hp) @ 4800 rpm -> 201 kw = +71kw
305nm (225lbft) @ 3300 rpm-> 454 nm = +149nm
or to compare..
Chev LS1 5.7L V8 (in current V8 Commodores) ;
220 kW @ 5000 RPM & 446 Nm @ 4400 RPM
Jeep 4.7L stroker :
201KW @ 4800rpm & 454nm @ 3400rpm
Clifford performance was right.... 6 DOES = 8 :) :) :) :) :)
The parts to date :
Parts amassed and approx landed costs in AUD$ to date :
1x 4.0L working block 130k of light use ;) (labour : 0.060" bore, acid dip, new welsh plugs, gaskets, etc)
http://www.angelfire.com/my/fan/BLOCK1.jpg
6x 4.0L rods retained (labour:to be shotpeened and balanced)
http://www.angelfire.com/my/fan/258_rods.jpg
1x 4.0L head (labour: get bigger valve seats to accept new valves and port job and general cleanup, de-burr, etc)
http://www.jeep4.0performance.4mg.com/images/ph1.jpg
1x 258 (4.2L) crank ("heavy" crank ie Jeep not AMC Eagle) from 1979 CJ7. labour: To have snout shortened 10mm to 4.0L length, needs to be balanced.
http://www.angelfire.com/my/fan/Crank_kit.jpg
8x Accel 26lb injectors (2nd hand off US ebay - $200) off a Camaro. labour: cleaning prior to use. 2x as working spares. Are a Bosch type II design. For 4.5/4.6 strokers using 258 rods more common 24 lb models from Fords and Chevs can be used.
http://www.aussiejeepimages.com/gallery2/d/29424-2/26lbinjectors.bmp
16x 2.02/1.60 ss valves & colletts (new off US ebay from engbldr - great service ! $134). use 12x in motor use other 4x for paperweights.
http://www.aussiejeepimages.com/gallery2/d/29427-2/202valves.bmp
1x Crane hydraulic cam part no (#753905 204/216 degree, from Summitracing.com - $200)
http://static.summitracing.com/global/images/prod/norm/crn-753905_m.jpg
1x Mopar 0.043" head gasket #P4529242 (from wyckoffchrysler.com, $80).NB stock is 0.051"
Parts to get
6x Ross forged custom pistons and rings ( www.rosspistons.com, $1000) specs : rod length : 6.125, bore size : 3.935, stroke : 3.895, head cc : 56.7, block height : 9.453
http://www.angelfire.com/my/fan/677P_pistons.jpg
12x hydraulic tappets (ebay, $40)
1x kit engine bearings (source locally - cam, crank, etc - $40)
1x adjustable MAP sensor mod ($15 is parts as per gojeep's site)
http://go.jeep-xj.info/MAP%20024.jpg
1x 62mm bored stock Throttle body (TB). As per gojeep's site. Got the flap wheels just gotta get into it ! Will save $$ on a billet 68mm one.
Considerations
May require a custom ECU (eg Wolf 3D). No mention found during research as a requirment but may be desirable to get a happier running stroker motor. Hopefully the adjustable MAP sensor with be sufficient for the early stages.
May also require hi-vol oil pump if stock one can't cope. Should be ok as very little hi-rpm (+5500) work forseen. Same reason for reusing the stock valve springs and retainers.
Possibly get a baffle welded into stock sump to avoid lost HP from splash. May require larger vol sump if cooling bnecomes an issue.
Possible require bigger radiator if cooling still an issue (Aussie desert cooler 3 flow unit $400).
Will be hitting an old 265 and a 245 Valiant crank at home with the vernier soon to see if either can be used in leu of the 258 one. Long shot that it will fit but it would push capacity up somewhere near 5.0L. Compression may become too high >9.7:1 and would require a thicker head gasket and different pistons and would also be unchartered ground. Nothings impossible though ! But the end result must still run on ULP and be within the budget.
Pics to come as the work begins. (as well as ones pilfered from Dino and GoJeep's sites amongst others)
Resources
Dino's great sites as above +
yahoo Stroker group : strokers@yahoogroups.com
Rockcrawler writeup by Tony Lopez : http://www.rockcrawler.com/techreports/stroker40/index.asp
I look forward to reading info on others stroker projects too :)
