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Valve Cover Adapter for Center Bolt Heads

Specs
Material Type:
Aluminum
Sold in Quantity:
Pair
Overall Thickness:
.375
Finish:
Natural
Gasket(s) Included:
Yes
Hardware Included:
Yes
Notes
Made to mount "perimeter" style valve covers on '86-newer heads.
Valve Cover Adapter for Center Bolt Heads

Click image to enlarge

Please NOTE the following about this product:

  • This item is sold as a pair.

Details

Reviews

Q & A

What's in the Box

As you know, you can't run a stud girdle when using centerbolt valve covers. These handy adaptors simply bolt to your centerbolt heads which allows you to use standard valve covers and stud girdles. O-ring seal on head side. Use standard gasket on valve cover side. Has bolt holes to use with early '60-'86 "straight bolt" valve covers as well as '55-'59 staggered bolt valve covers.

We also carry adaptor plates (# 910-17145) to put '87 and newer center-bolt valve covers on '60-'86 heads.
 

Customer Reviews

Rated 4.3 out of 5 by 16 reviewers.
RATING BREAKDOWN
16 reviews
5 Stars
9
4 Stars
4
3 Stars
2
2 Stars
1
1 Star
0
RECOMMEND THIS PRODUCT:

Chash
VALDOSTA Ga
Product Rating

OPERFECT FIT

March 11, 2015
PERFECT FIT FOR MY VINTAGE FINNED CAL CUSTOM VALVE COVERS
Yes, I recommend this product.
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joes63
Verified Purchaser
florida
Product Rating

great idea

May 20, 2014
They didn't fit between the trunions on the roller rockers that I am using but after some mill work, and some filling on the center webs they worked just fine.
Yes, I recommend this product.
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bruiser77
Verified Purchaser
Michigan, USA
Product Rating

Use your favorite valve covers

June 28, 2013
Quality piece cnc machined from billet aluminum and hardware is included
Cons:
  • didn't come with instructions
Yes, I recommend this product.
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geiger
Verified Purchaser
Grande Prairie, AB, Canada
Product Rating

this works great and helps

April 20, 2013
thank you .this works great and help with the look of the truck engine space
Yes, I recommend this product.
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vette60
Verified Purchaser
Springfield, MA, USA
Product Rating

great product works like oem

February 08, 2013
parts have good fit finish work good for using stock valve covers on center bolt heads
Yes, I recommend this product.
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JWright75
Verified Purchaser
Beggs, OK
Product Rating

Be cautious

June 27, 2012
Could not use on my dirt motor for a couple reasons. First problem was our raised pushrod guides would not fit with them but switched up flat guides mo problem. Now the big problem was they will not fit with a big rocker arm. Have seen descriptions that say must use narrow rockers. So be careful in ordering.
No, I would not recommend this product.
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Enthusiast
Verified Purchaser
Illinois
Product Rating

Works but issues

September 13, 2012
This part has two flaws. 1) needs to be modified to clear the valve springs. 2) side blot holes go all the way through so valve cover bolts if to long can push through and warp the adapter.
Pros:
  • Lightweight
No, I would not recommend this product.
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Someone
PA
Product Rating

So so but wont work in all application..

August 15, 2011
Will not work if you use guideplates. Better off running a tall valve cover to clear stud girdles.
Pros:
  • Easy To Install
  • Durable
No, I would not recommend this product.
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tw7256
Rock kansas
Product Rating

Valve cover adapters

August 30, 2010
I had to chamfer to clear my roller rocker arms.
Yes, I recommend this product.
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Herb the engine builder
Williamston, NC
Product Rating

Quality made item

August 27, 2010
Could not use them on the heads I am using without extensive modification.
Pros:
  • First quality item
Yes, I recommend this product.
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Page 1 of 2

Product Q&A

10 questions : 13 answers

In need of info on the part #910-17145 looking to put center bolt covers on older heads

1 answers
MafiaMade
April 01, 2015

In need of info on the part #910-17145 looking to put center bolt covers on older heads

Answers

April 01, 2015
EricM
These are made for the opposite scenario, when someone desires perimeter bolt valve covers to be installed on center bolt heads. Sorry we do not offer an adapter like you are after.

Could these be used to adapt straight bolt heads to staggered bolt valve covers?

2 answers
Offytripower
Utah
October 30, 2014

Could these be used to adapt straight bolt heads to staggered bolt valve covers?

Answers

March 12, 2015
Chash
Yes
October 30, 2014
EricM
It may be possible to modify these to adapt for the early style staggered bolt pattern valve cover but we have never tried that before.

installation Which side does the adapter mount to the heads? Is it the side with the rubber ring that is fitted to the adapter? Or do I use a typical gasket in between head and adapter and mount the valve cover to the adapter with the rubber ring.

2 answers
Vince1966
Pittsburgh, PA, USA
October 22, 2014

installation Which side does the adapter mount to the heads? Is it the side with the rubber ring that is fitted to the adapter? Or do I use a typical gasket in between head and adapter and mount the valve cover to the adapter with the rubber ring.

Answers

March 12, 2015
Chash
I used a reg gasket down with O ring up towards valve cover . works perfect .
October 22, 2014
EricM
The rubber O ring goes toward the cylinder head. A typical valve cover gasket will be used between the valve cover and the adapter.

will these work on a stock 88 305 with roller rockers?

2 answers
bigbear
Kansas, USA
March 09, 2014

will these work on a stock 88 305 with roller rockers?

Answers

May 21, 2014
joes63
They didn't work for me without milling a little on the center webs. the webs where to thick to go between the truions on my roller rockers
March 10, 2014
EricM
Yes these will bolt to your engine but you will need to check for clearance to your roller rockers when installing these adapters. Some roller rockers are wider than others and they can come into contact with this adapter. If they do then you may need to grind some clearance into the adapter.

will these adapters work on a ls series engine? im looking for a adapter to adapt from lsx center bolt heads to a lsx perimeter valve cover.

1 answers
stevenwade
Lynchburg, VA, USA
November 03, 2013

will these adapters work on a ls series engine? im looking for a adapter to adapt from lsx center bolt heads to a lsx perimeter valve cover.

Answers

November 04, 2013
Jason
Part number 91017157 These adapters will work on the 86 and newer center bolt heads and make use of the perimeter bolt style earlier valve covers. They will even work on the 55-59 staggered perimeter bolt valve covers. Sorry, these adapters will not work with the LS cylinder heads.

does these spacers work on LT-1 also? Camaro -94 engine.

1 answers
February 14, 2012

does these spacers work on LT-1 also? Camaro -94 engine.

Answers

February 16, 2012
John
Part number 91017157 These adapters will work on the 86 and newer center bolt heads and make use of the perimeter bolt style earlier valve covers. They will even work on the 55-59 staggered perimeter bolt valve covers.

How thick is the adapter from bottom to top?

1 answers
June 17, 2011

How thick is the adapter from bottom to top?

Answers

June 20, 2011
Jason
The adaptor plates are 3/8" thick

Good morning I just purchased these adapters and was wondering what the torque should be on the mounting nuts. thank you

1 answers
October 18, 2011

Good morning I just purchased these adapters and was wondering what the torque should be on the mounting nuts. thank you

Answers

October 18, 2011
John
Part # 91017157 The center mount stud nuts could be torqued from 75-100 inch pounds and Loctite or thread lock could be used.

CAN I RUN SHAFT MOUNT ROCKERS WITH THIS ADAPTOR ?

1 answers
ORONOGO MO
January 11, 2011

CAN I RUN SHAFT MOUNT ROCKERS WITH THIS ADAPTOR ?

Answers

January 14, 2011
Anonymous
No

Hi I have a zz4 GM crate engine with center bolt valve covers. Will your adapter fit these heads

1 answers
roda
October 02, 2012

Hi I have a zz4 GM crate engine with center bolt valve covers. Will your adapter fit these heads

Answers

October 03, 2012
Jason
Part number 91017157 These adapters will work on the 86 and newer center bolt heads and make use of the perimeter bolt style earlier valve covers. They will even work on the 55-59 staggered perimeter bolt valve covers
Page 1 of 1

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