UMI Performance
UMI Performance 78-88 GM G-Body Engine Side Solid Engine Mounts
* Images may be a representation and may not reflect the actual product.
Product Details
Motor Mount - Bolt-On - Hardware Included - Steel - Black Powder Coat - GM G-Body 1978-88 - Kit
The P/N 0058 heavy duty engine mounts for GM G-Body cars takes the place of the heavy factory clamshell mount. It places the Small Block Chevy in exact factory location and uses our popular P/N 90051 solid motor mounts or can be used with the factory rubber mounts. Tough 3/16” laser cut brackets and Grade 8 hardware can handle as much horsepower as you can throw at them. When used with P/N 90051, solid engine mounts improve responsiveness and help prevent engine movement, which can help in tight packaging situations (large header primaries, turbos, etc). Solid engine mounts work best in racing applications and may contribute to increased Noise, Vibration and Harshness. Available in gloss black powder coat. These engine mounts are proudly used on UMI’s G-Body test car, 1979 Monte Carlo “Green Machine”. 100% manufactured, tested and raced out of Philipsburg, PA – USA. Note: Heavy duty engine mounts may not work with Oldsmobile or Pontiac engines.
UMI Performance 78-88 GM G-Body Engine Side Solid Engine Mounts, UMI Performance Heavy Duty Engine Mounts
UMI Performance 78-88 GM G-Body Engine Side Solid Engine Mounts
1978-1988 GM G-Body Engine Side Solid Engine Mounts
Gloss black powder coat finish
Engine Mounts
UMI Performance Heavy Duty Engine Mounts
Engine Mounts
UMI Performance 78-88 GM G-Body Engine Side Solid Engine Mounts, UMI Performance Heavy Duty Engine Mounts
Vehicle Fitment
Please verify year, make, model, and any notes before ordering.
- 1978-1988Chevrolet G-Body
Product Specs
- Brand
- UMI Performance
- Part Number
- 90058
- Catalog Number
- 001588188
- Product Line
- Engine Mounts
- Category
- Engines & Parts
- Type
- Engine Mounts
- UPC / Barcode
- 90058
- Vendor Product Category
- Engine Components
- Vendor Product Subcategory
- Engine Mounts
- Length
- 12.35 in
- Width
- 4.90 in
- Height
- 4.55 in
- Weight
- 4.15 lb
- Units Per SKU
- 1
- Freight / LTL
- No
- Ship Alone
- No
- Air Restricted
- No
- Prop 65
- Y
- CARB Approved
- Yes
- Clearance Item
- No
Shipping & Availability
This item is showing available inventory. Most in-stock performance parts ship quickly, but timing can vary by warehouse, vendor cut-off time, holidays, and carrier pickup.
PROP 65 WARNING: This product can expose you to chemicals, which are known to the State of California to cause cancer or birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
Inventory shown: 1 available as of 6/3/2026.
UMI Performance warrants all UMI Performance products for a period of two (2) years from the original date of purchase.
This warranty is valid against defects in materials and workmanship for the two (2) year warranty period. It is not valid against defect resulting from, but not limited to:
Misuse and/or abuse, neglect or accident.
Exceeding the items design limits.
Improper installation.
Acts of God, including lightning, floods, earthquakes, fire or high winds.
Damage in handling, including damage encountered during shipment.
This warranty is valid for the original purchaser of the UMI Product. Warranty is not transferable or valid for second ownership.
This warranty shall be considered void if the warranted product is in any way altered, adjusted, tampered with or defaced.
The two (2) year warranty does not apply to normal wear and tear (the gradual deterioration of an asset which results naturally from use and/or age, i.e. bearings, bushings, etc.).
Non UMI manufactured parts are not covered or valid under this UMI Performance warranty.
UMI Performance cannot guarantee compatibility or performance of its products with other components used in conjunction with UMI Performance products.
UMI Performance cannot assume responsibility for any damages to UMI Products nor for claims for personal injury or property damage resulting from the use of UMI Performances products or the improper operation thereof or consequential damages arising from the products or use of the products.
UMI Performance two (2) year warranty excludes incidental charges incurred by the end user in the event of breakage (towing, labor, installation, etc.). By their very nature, competition suspension parts are continuously expected to exceed to their limits (either by race or road use). UMI suspension components are designed to withstand intense race conditions, although it is impossible to control the quality of installation or the varying conditions in which they are used.
This warranty supersedes all other warranties and may only be modified by statement in writing, signed by UMI Performance owners/principals.
All Warranties implied by law, including the warranties of merchantability and fitness for a particular purpose, are hereby limited to the warranty period herein and shall expire at the end of such period.
Reviews & Questions
Real product feedback when available, plus quick ways to get fitment or product help.
Other Popular Parts
LMPerformance is proud to offer our customers hundreds of UMI Performance chassis and suspension components and parts. It gives us great satisfaction to have a line of parts designed and manufactured in the USA entirely within its facility located in the small town of Philipsburg, Pennsylvania. UMI Performance's facility features CNC machining, both milling and turning CNC’s, band sawing, press brake operation, MIG and TIG welding, sand blasting, plasma cutting and powder coating. UMI Performance also installs and tests every chassis and suspension component it makes, right here in the USA, to ensure that they perform as designed.
Make your classic muscle car handle like a modern machine with parts from UMI Performance! Built using the very latest design and machining technology,. We have found that UMI Performance suspension & parts focuses on muscle cars from the 1960s to today A-bodies, F-bodies, B-bodies, G-bodies, and Mustangs. Choose from our 100's of UMI Performance parts like crossmembers, panhard bars, control arms, K-members, subframe connectors, and more. Many parts fit like stock replacements, so they’re easy to install, but you’ll immediately notice tighter handling that’s easy to tune to your needs. These products and parts greatly add to LMPerformance's line of offerings to our customers.
Our search for good manufacturers and quality products showed LMPerformance that UMI Performance began in 2003 under the leadership of Ryan Kirkwood and the guidance of his father Denny. Together this father and son team developed a large variety of products for many makes and models of GM vehicles as well as the Ford Mustang. Ryan saw a large demand for suspension and chassis products, and felt the market was lacking of options and full of highly priced items. So, on May 31st 2003, UMI began its journey in the aftermarket suspension industry with a 1994 Ford Mustang GT Convertible. This car was used as a test bed for the beginning stages of UMI’s Fox and SN95 platform products. The products began to move very quickly, becoming almost impossible to keep in stock. The faster they manufactured them the quicker they sold. In late 2003, UMI purchased a 2000 Pontiac Firebird Trans Am WS6 which was used as their F-Body platform design vehicle. Slowly, products began to arise on the market for the GM F-Body, and quickly UMI Performance became a well respected company, becoming one of the largest suspension manufactures in today’s market, enhancing our line products.
To confirm LMPerformance's selection of UMI Performance as a supplier our further research on UMI indicated it operates out of a 35,000 square foot facility - this new facility located in Philipsburg, PA was recently acquired by UMI in March, 2011. UMI Performance manufactures 99.9% of their products within their facility from start to finish - from raw 24 foot bars of tubing to a finished product on your door step.
Take a look at the nonpareil products from UMI PERFORAMANC on the web site and see what we mean, parts like the UI K Member for your 1993-1997 Pontiac Firebird in the Road Race Version that is manufactured with the racing aficionado in mind because it can withstand the stressful demands aggressive driving puts on it or for your 1993-2002 Chevy Camaro the Front Upper and Lower A-Arm Kit from UMI that are fabricated to add front end rigidity and at the same time eliminate the flex you probably have noted in your factory A-Arms. And for you owners of the iconic 1982-1992 Chevrolet Camaro UMI made a sui generis Tunnel Mounted Torque Arm to fit the TH350 AND T5 transmissions designed so that it removes the front mounting point of the torque arm so that it protects the tail shaft from damage and it is perfect when you have swapped your transmission and cannot use a clamshell torque arm. Take a look at the potpourri of chassis and suspension parts from the consummate UMI PERFORMANCE and find the one that you need for your Chevrolet, Pontiac or Ford and let LMPERFORMANCE help you get it at a competitive price and with free shipping.
Review our return, cancellation, shipping, warranty, and product image policies before ordering.
Contact us with questions before ordering
California Residents: Prop 65 WARNING: This product MAY contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling. For more information, visit www.P65Warnings.ca.gov
California Residents: TIRE WARNING: LMPerformance will not ship Tires to California.
Legal: Some or all of these parts may not comply with Federal, State, Province, and/or Local laws, ordinances, and regulations. Buyer takes all responsibility to ensure that any modifications or upgrades that have done conform to all applicable laws and regulations for road use, especially pertaining to safety and emissions. LMPerformance is not responsible for buyer not complying with Federal, State, Province, and/or Local laws, ordinances, and regulations. This policy shall be in force for all past, current, and future purchases from LMPerformance, Inc. LMPerformance will not ship ANY non-CARB compliant products to California where California requires products to be CARB certified such as Catalytic Converters and Induction Kits.
Free Shipping: Please note FREE Shipping refers to shipping within the contiguous continental US only. All other locations extra. Some items that require Truck Freight Delivery will require a Truck Freight surcharge. This surcharge is still a discounted shipping amount that is lower then the actual truck freight shipping charge that is charged to LMP. LMP will try to still give the lowest price possible for truck freight items.
Images: Images may be a representation and may not reflect the actual product. Examples would be SPEC stage 3 clutch kits which all use the same photo.
TYPOS: LMPerformance tries to present the best most accurate information on our website. Sometimes we get mistakes in product information sent from vendors such as typos. We can not be responsible for these typos, if you see something that does not look right please let us know before ordering so we can double check for you first. LMPerformance will not pay for typos in any way, monetarily or otherwise.
Price Errors: In the event that a product has mistakenly been listed at an incorrect price, We reserve the right to refuse or cancel any orders placed for product listed at the incorrect price. We reserve the right to refuse or cancel any such orders whether or not the order has been confirmed and your account charged. If your payment type has already been charged for the purchase and your order is cancelled, a full refund to your orignial payment method in the amount of the incorrect price will be issued.
Special Order ITEMS: Some items are Special Ordered and may not be returnable, or even cancellable as they are going into production specifically because you ordered them. Special Ordered items can have a 5-35% cancelation fee.
Cancellations: Instock orders cannot be canceled due to our automated ordering & fast shipping system. To keep our prices low, all cancelations are subject to a 5% cancelation fee to cover transaction processing fees. We reserve the right to charge up to a 10% cancellation fee for cancelled orders due to merchant fees, Special Order fees and the cost of processing and shipping orders.When you request a cancellation of an order or a part, please note that it may take time for a manufacturer to cancel an order if the order is drop-shipped. We also have to confirm that the product has not shipped. If the product has shipped then this must be processed as a return.Also note that sometimes products ship more quickly than expected, so we recommend that you do not purchase alternative products until receiving final confirmation of the cancellation.
Returns: We cannot accept returns on parts that have been used or installed. No returns will be accepted after 30 days. All Returns must be in original packaging. Prior authorization must be given before any return can be made. Up to a 25% Restocking Fee may apply. Special Orders may be subject to Additional Manufacturer Restock Fees as well. Shipping cost will not be refunded.Hoods as well as PCM Programmers may not be returned unless defective and only for replacement. ALL returns must be first filed using our online form found here: https://www.lmperformance.com/returns.
Lost Order Claims All lost order/package claims must be made within 5 days of the shipping date or tracking information delivery date. All claimes made after this date will not be accepted due to Shipping companies policies of filing loss claims.
Damaged Items or Incorrect Items: Please contact us right away if your item has been damaged in shipping or are incorrect. Please note that we will ship replacement items the same method of shipping the order was originally placed for. LMPerformance can not ship packages overnight at our cost if the original shipping was not also overnight. Claims must be filed in order for replacement parts to be shipped.
Warranties:Any warranty claims must be placed with the manufacturer. All of the products sold by LMPerformance, regardless of the manufacturer, are designed for Racing and Performance applications. Many of our manufacturers offer NO WARRANTY on their products, either stated or implied, due to the unusual stresses placed on the parts and because we have no control over how they are installed and used. Many of these products are designed for off-road use only and are not legal for use on public highways. If you have a question about the warranty on a specific product, please e-mail or call us. Buyer assumes all risk and liability associated with these products.
Installation: We are not responsible for or any costs associated with the installation or the improper installation of any products. Purchaser assumes the risk associated with the installation of products. We, along with the manufacturer of each product are not responsible for any direct or indirect damage to the vehicle, personal, or costs incurred from the use of products.