once your engines hp and torque levels start to significantly exceed the factory levels its not at all uncommon for the engines twisting movement in the frame to start stressing the factory motor mounts, this can result in difficult shifts due to linkage geometry changes or jammed throttles etc.
On the motor mounts, the driver side is under extension or stretching and the passenger is under compression, as the engine torque increases with shifts etc. so the load is on the driver side. This is the reason for the solid driver mount most guys use is to limit engine movement,. As far as the trans goes, I like having something to absorb any vibes in the car so Ive generally used the hard plastic/ or POLY trans mounts. The weaker part is the aluminum trans case
many guys go to the stronger aftermarket poly motor mounts or add a short section of chain from the drivers side cylinder head to the drivers side frame to limit the shock loads on the motor mounts that speed shifts, high stall speed converters, higher rear gears and slicks, and much higher torque loads impart to the factory mounts, the first time you bust an engine mount and the throttle jams wide open , you might see the advantages
many guys simply bolt a short section of chain or an adjustable strap with heim joint ends,between the left side car frame and some solid location like a bolt on the the left engine cylinder head that has just a bit of slack so as the engine torque increases stress on the motor mounts it tightens up as the distance between the left cylinder head and frame increases and significantly reduces the load on the motor mount.
ALWAYS run a good separate electrical ground strap between the engine and frame , transmission and motor mounts are notoriously bad electrical ground connections to the frame.
clean the battery terminals and replace the two cables, make sure you use similar to factory cables, and connect to starter and frame or as factory installed.
buy and correctly install TWO ground straps
be sure you clean metal contact areas and once install spray with good corrosion barrier
install
1 engine to frame
1- transmission to frame
run the battery neg to the frame also
http://garage.grumpysperformance.co...urrent-flow-grounds-and-more.3504/#post-54625
http://garage.grumpysperformance.co...hooting-tip-for-electronics.11317/#post-51557
starter support brackets can be helpful
396588 = BB or Caddy
3965589 = 168 tooth SB '66-'91
354353 = 153 tooth '66-'91
3851294 = '64-'69 Vette
3816511 = '62-'68 SB
Attachment: brackets.jpg (53.42 KB) 4 View(s)
POLY MOTOR MOUNTS and a decent grade 8 set of mount bolts, with loc-tite on the threads will help , check the bolt length, diameter and thread pitch carefully.
3/8 mount to block and or -7/16" bolt about 3.5" long is the common solution,to broken stock motor mount in a high stress application,
btw on some motor mounts the bolt holes either don,t line up exactly or the holes a bit under sized so a bit of drill bit time might be required to get the thru bolt to clear easily, so don,t get crazy, test fit the bolt before you install the mounts
when planing on fabricating a large bracket like that engine mount plate its frequently a good idea to buy , cut and test fit
a pattern made from dirt cheap clear plastic before starting on rather expensive steel or aluminum, to get all the necessary mods and clearances worked out, the huge advantage of clear plastic is you can easily see where you need bolt holes or some item that moves during operation (like suspension) or more easily let you recognize early in the fabrication process that theres always a compromise some place to be considered, parts like STARTERS , OIL FILTERS AND HEADERS that might become nearly impossible to work on if the brackets in place
http://www.homedepot.com/p/11-in-x-14-in-Non-glare-Styrene-Sheet-1S11143A/202771350
if youve built a real torque monster solid mid plate mounts might be a good idea
http://stores.channeladvisor.com/Summit ... s/CEE-4031
http://garage.grumpysperformance.co...ng-engine-accessory-brackets.8523/#post-29916
http://garage.grumpysperformance.co...ng-engine-accessory-brackets.8523/#post-29916
http://www.kmjent.com/cart/product.php?productid=1047
http://www.kmjent.com/cart/product.php? ... 602&page=1
IF your having trouble getting motor mounts to line up correctly ,you do realize that chevy motor mounts come in several styles and heights
1- 11/16"
1- 3/4"
2 -1/8"
2- 3/8"
2 -9/32"
theres also spacers for motor mounts
Part # Description
62535 Motor Mount Shim Kit
1/16", 1/8", and 3/16" thick, 2 ea.
Standard Chevrolet bolt pattern
Works great with Chevy Motor Mounts 62500, 62510, 62515, & 62530
Used to make slight adjustments to engine height to compensate for minor oil pan, linkage, and header interference
Great addition to engine swap kits
Part # Description
http://www.moroso.com/eb/catalog/naviga ... =main.menu
theres far more than just these designs
viewtopic.php?f=71&t=545&p=684&hilit=engine+mounts#p684
viewtopic.php?f=50&t=704&p=1573&hilit=engine+mounts#p1573
viewtopic.php?f=38&t=879&p=1377&hilit=engine+mounts#p1377
viewtopic.php?f=87&t=783&p=4910&hilit=engine+mounts#p4910
viewtopic.php?f=50&t=44&p=103&hilit=engine+mounts#p103
viewtopic.php?f=38&t=200&p=235&hilit=engine+mounts#p235
http://www.speedwaymotors.com/m/405_Eng ... -Kits.html
http://www.racecarparts.com/Big_Block_Chevy.html
http://www.eficonnection.com/eficonnection/58x.aspx
http://www.tperformance.com/street_rod_ ... or_mounts/
http://www.brokenkitty.com/xj/xjv8.htm
http://www.highangledriveline.com/unlti ... system.htm
http://www.highangledriveline.com/toy_flange.html
http://www.mrdriveshaft.com/U-Joint%20P ... 20U-Joints
http://www.pirate4x4.com/tech/billavist ... ndex4.html
https://sdp-si.com/eStore/Direct.asp?GroupID=574
http://www.billshotrodcompany.com/673/5301.html
http://www.speedhound.com/lsxswap.html
http://www.billetspecialties.com/assets/pdf/747.pdf
http://kwikperf.com/
http://www.progressiveautomotive.com/motor.htm
http://chucker54.stores.yahoo.net/enginemounts.html
http://www.sachserodshop.com/pdf/5.pdf
http://www.tdperformance.com/categories/?id=3102
http://www.hotrodsusa.com/store/bills.html
http://www.campbellenterprises.com/motorplates.htm
http://www.alangrovecomponents.com/
http://chucker54.stores.yahoo.net/enginemounts.html
http://garage.grumpysperformance.com/index.php?threads/bolts-a-bit-of-useful-info.4868/#post-13372
http://competitionengineering.com/catal ... Code=11025
http://engine-swaps.com/frames/frame_Torquestrap.html
http://www.carcraft.com/techarticles/po ... index.html
http://www.fordmuscle.com/archives/2000/04/quicktips/
while hardly high tech,
adding a simple length of 3/8" chain from the drivers side frame to a bolt in the drivers side cylinder head will prevent a great deal of torque damage to motor mounts
and yes a commercial version looks better but its not significantly more effective
mark Bradley posted this info on a torque strap tp limit engine movement ,
to help the fan not hit the fan shroud
http://competitionengineering.com/catal ... Code=10029
if you want to get fancy and do a really nice job you can fabricate custom, adjustable length torque straps with HEIM joint swivel ends,and heavy wall stainless or chrome moly steel tubing and weld a lower bracket to the frame
http://www.pacificnorthwestbearing.net/ ... _info.html
https://www.speedwaymotors.com/shop/heim-joints-and-rod-ends~14-16-578-31189
https://www.barnes4wd.com/Heim-Joints-Enduro-Joints-and-Hardware_c_7.html
https://www.ruffstuffspecialties.com/catalog/RODENDS.html
On the motor mounts, the driver side is under extension or stretching and the passenger is under compression, as the engine torque increases with shifts etc. so the load is on the driver side. This is the reason for the solid driver mount most guys use is to limit engine movement,. As far as the trans goes, I like having something to absorb any vibes in the car so Ive generally used the hard plastic/ or POLY trans mounts. The weaker part is the aluminum trans case
many guys go to the stronger aftermarket poly motor mounts or add a short section of chain from the drivers side cylinder head to the drivers side frame to limit the shock loads on the motor mounts that speed shifts, high stall speed converters, higher rear gears and slicks, and much higher torque loads impart to the factory mounts, the first time you bust an engine mount and the throttle jams wide open , you might see the advantages
many guys simply bolt a short section of chain or an adjustable strap with heim joint ends,between the left side car frame and some solid location like a bolt on the the left engine cylinder head that has just a bit of slack so as the engine torque increases stress on the motor mounts it tightens up as the distance between the left cylinder head and frame increases and significantly reduces the load on the motor mount.
ALWAYS run a good separate electrical ground strap between the engine and frame , transmission and motor mounts are notoriously bad electrical ground connections to the frame.
Grote Ground Strap Braided, 18 In 84-9465 | Zoro
Order Grote Ground Strap Braided, 18 In, 84-9465 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.
www.zoro.com
buy and correctly install TWO ground straps
be sure you clean metal contact areas and once install spray with good corrosion barrier
install
1 engine to frame
1- transmission to frame
run the battery neg to the frame also
http://garage.grumpysperformance.co...urrent-flow-grounds-and-more.3504/#post-54625
http://garage.grumpysperformance.co...hooting-tip-for-electronics.11317/#post-51557
starter support brackets can be helpful
396588 = BB or Caddy
3965589 = 168 tooth SB '66-'91
354353 = 153 tooth '66-'91
3851294 = '64-'69 Vette
3816511 = '62-'68 SB
POLY MOTOR MOUNTS and a decent grade 8 set of mount bolts, with loc-tite on the threads will help , check the bolt length, diameter and thread pitch carefully.
3/8 mount to block and or -7/16" bolt about 3.5" long is the common solution,to broken stock motor mount in a high stress application,
btw on some motor mounts the bolt holes either don,t line up exactly or the holes a bit under sized so a bit of drill bit time might be required to get the thru bolt to clear easily, so don,t get crazy, test fit the bolt before you install the mounts
when planing on fabricating a large bracket like that engine mount plate its frequently a good idea to buy , cut and test fit
a pattern made from dirt cheap clear plastic before starting on rather expensive steel or aluminum, to get all the necessary mods and clearances worked out, the huge advantage of clear plastic is you can easily see where you need bolt holes or some item that moves during operation (like suspension) or more easily let you recognize early in the fabrication process that theres always a compromise some place to be considered, parts like STARTERS , OIL FILTERS AND HEADERS that might become nearly impossible to work on if the brackets in place
http://www.homedepot.com/p/11-in-x-14-in-Non-glare-Styrene-Sheet-1S11143A/202771350
if youve built a real torque monster solid mid plate mounts might be a good idea
http://stores.channeladvisor.com/Summit ... s/CEE-4031
http://garage.grumpysperformance.co...ng-engine-accessory-brackets.8523/#post-29916
http://garage.grumpysperformance.co...ng-engine-accessory-brackets.8523/#post-29916
http://www.kmjent.com/cart/product.php?productid=1047
http://www.kmjent.com/cart/product.php? ... 602&page=1
IF your having trouble getting motor mounts to line up correctly ,you do realize that chevy motor mounts come in several styles and heights
1- 11/16"
1- 3/4"
2 -1/8"
2- 3/8"
2 -9/32"
theres also spacers for motor mounts
Part # Description
62535 Motor Mount Shim Kit
1/16", 1/8", and 3/16" thick, 2 ea.
Standard Chevrolet bolt pattern
Works great with Chevy Motor Mounts 62500, 62510, 62515, & 62530
Used to make slight adjustments to engine height to compensate for minor oil pan, linkage, and header interference
Great addition to engine swap kits
Part # Description
http://www.moroso.com/eb/catalog/naviga ... =main.menu
theres far more than just these designs
viewtopic.php?f=71&t=545&p=684&hilit=engine+mounts#p684
viewtopic.php?f=50&t=704&p=1573&hilit=engine+mounts#p1573
viewtopic.php?f=38&t=879&p=1377&hilit=engine+mounts#p1377
viewtopic.php?f=87&t=783&p=4910&hilit=engine+mounts#p4910
viewtopic.php?f=50&t=44&p=103&hilit=engine+mounts#p103
viewtopic.php?f=38&t=200&p=235&hilit=engine+mounts#p235
http://www.speedwaymotors.com/m/405_Eng ... -Kits.html
http://www.racecarparts.com/Big_Block_Chevy.html
http://www.eficonnection.com/eficonnection/58x.aspx
http://www.tperformance.com/street_rod_ ... or_mounts/
http://www.brokenkitty.com/xj/xjv8.htm
http://www.highangledriveline.com/unlti ... system.htm
http://www.highangledriveline.com/toy_flange.html
http://www.mrdriveshaft.com/U-Joint%20P ... 20U-Joints
http://www.pirate4x4.com/tech/billavist ... ndex4.html
https://sdp-si.com/eStore/Direct.asp?GroupID=574
http://www.billshotrodcompany.com/673/5301.html
http://www.speedhound.com/lsxswap.html
http://www.billetspecialties.com/assets/pdf/747.pdf
http://kwikperf.com/
http://www.progressiveautomotive.com/motor.htm
http://chucker54.stores.yahoo.net/enginemounts.html
http://www.sachserodshop.com/pdf/5.pdf
http://www.tdperformance.com/categories/?id=3102
http://www.hotrodsusa.com/store/bills.html
http://www.campbellenterprises.com/motorplates.htm
http://www.alangrovecomponents.com/
http://chucker54.stores.yahoo.net/enginemounts.html
http://garage.grumpysperformance.com/index.php?threads/bolts-a-bit-of-useful-info.4868/#post-13372
http://competitionengineering.com/catal ... Code=11025
http://engine-swaps.com/frames/frame_Torquestrap.html
http://www.carcraft.com/techarticles/po ... index.html
http://www.fordmuscle.com/archives/2000/04/quicktips/
while hardly high tech,
adding a simple length of 3/8" chain from the drivers side frame to a bolt in the drivers side cylinder head will prevent a great deal of torque damage to motor mounts
and yes a commercial version looks better but its not significantly more effective
mark Bradley posted this info on a torque strap tp limit engine movement ,
to help the fan not hit the fan shroud
To limit the engine rotation under heavy acceleration I built an adjustable torque bar/strap.
I purchased the parts from Speedway Motors.
PartNo, Description, Price
175-6045-LH, 6pc 1/2x20 Jam nut LH, 2.99
175-6045-RH, 6pc 1/2x20 Jam nut RH, 2.99
910-34212-7, 7” Swedged tube, 11.99
175-0305, 1/2” LH heim joint, 5.99
926-10896, Sway bar end link kit, 7.99
I created a plate/arm that bolts to the front of the drivers side cylinder head and extends past the p/s pump. The heim joint connects there and runs directly down to a bracket on the engine cross member. The lower bracket connects with bushings for a sway bar end.
http://competitionengineering.com/catal ... Code=10029
if you want to get fancy and do a really nice job you can fabricate custom, adjustable length torque straps with HEIM joint swivel ends,and heavy wall stainless or chrome moly steel tubing and weld a lower bracket to the frame
http://www.pacificnorthwestbearing.net/ ... _info.html
https://www.speedwaymotors.com/shop/heim-joints-and-rod-ends~14-16-578-31189
https://www.barnes4wd.com/Heim-Joints-Enduro-Joints-and-Hardware_c_7.html
https://www.ruffstuffspecialties.com/catalog/RODENDS.html
Last edited by a moderator: