FRAMING JOHN DELOREAN - ON VOD www.framingjohndeloreanfilm.com
Page 1 of 5 1 2 3 ... LastLast
Results 1 to 10 of 43

Thread: got any head bolts you can part with?

  1. #1
    Senior Member Parzival's Avatar
    Join Date:  Apr 2018

    Location:  Florida

    Posts:    326

    got any head bolts you can part with?

    I'm close to putting my heads back on, I bought some head bolts from Delorean go, but have now been informed that they are wrong, and will result in eventual failure of the head gasket. Huston is out of head bolts, and Delorean Industries is out until they produce another run, which may be soon, but not sure.
    So if anyone out there has a NOS set of head bolts laying around, I'd be happy to take them off your hands.

  2. #2
    Senior Member Giamanut's Avatar
    Join Date:  Sep 2019

    Location:  Spokane

    Posts:    128

    My VIN:    5051

    Quote Originally Posted by Parzival View Post
    I'm close to putting my heads back on, I bought some head bolts from Delorean go, but have now been informed that they are wrong, and will result in eventual failure of the head gasket. Huston is out of head bolts, and Delorean Industries is out until they produce another run, which may be soon, but not sure.
    So if anyone out there has a NOS set of head bolts laying around, I'd be happy to take them off your hands.
    Wow how did they send you the wrong bolts? I got mine about a week ago from Houston!

  3. #3
    Senior Member Giamanut's Avatar
    Join Date:  Sep 2019

    Location:  Spokane

    Posts:    128

    My VIN:    5051

    Quote Originally Posted by Giamanut View Post
    Wow how did they send you the wrong bolts? I got mine about a week ago from Houston!
    https://www.volvopartswebstore.com/s...rimLevel=28245

  4. #4
    Senior Member Parzival's Avatar
    Join Date:  Apr 2018

    Location:  Florida

    Posts:    326

    Quote Originally Posted by Giamanut View Post
    Wow how did they send you the wrong bolts? I got mine about a week ago from Houston!
    Its not that they are wrong, its what they sell. According to some advice I got from an experienced Delorean tech, they are not rated high enough for use in the PRV. The are bolts for a chevy, and they do fit, but apparently will stretch and cause the a head gasket leak. I tried to get some NOS bolts from huston but they only had 12 left in stock, and mixing and matching head bolts seems like a bad idea so I passed on them.

  5. #5
    Administrator Ron's Avatar
    Join Date:  Jun 2011

    Location:  North GA

    Posts:    6,176

    Club(s):   (SEDOC) (DCUK)

    Quote Originally Posted by Parzival View Post
    Its not that they are wrong, its what they sell. According to some advice I got from an experienced Delorean tech, they are not rated high enough for use in the PRV. The are bolts for a chevy, and they do fit, but apparently will stretch and cause the a head gasket leak. I tried to get some NOS bolts from huston but they only had 12 left in stock, and mixing and matching head bolts seems like a bad idea so I passed on them.
    I find it hard to believe that Chevy bolts are not rated high enough. But that be the case, call Summit they have Chromoly, Cadmium....

  6. #6
    Senior Member Bitsyncmaster's Avatar
    Join Date:  May 2011

    Location:  Leonardtown, MD

    Posts:    9,005

    My VIN:    03572

    What do the rating numbers on the heads of the bolts say?
    Dave M vin 03572
    http://dm-eng.weebly.com/

  7. #7
    Senior Member Giamanut's Avatar
    Join Date:  Sep 2019

    Location:  Spokane

    Posts:    128

    My VIN:    5051

    Quote Originally Posted by Parzival View Post
    Its not that they are wrong, its what they sell. According to some advice I got from an experienced Delorean tech, they are not rated high enough for use in the PRV. The are bolts for a chevy, and they do fit, but apparently will stretch and cause the a head gasket leak. I tried to get some NOS bolts from huston but they only had 12 left in stock, and mixing and matching head bolts seems like a bad idea so I passed on them.
    What chevy ? and prv bolts also stretch did you check the link I posted they are item number 44 in the diagram.
    Funny thing is that each cylinder makes about 22 HP I think DeloreanGo head bolts are fine. My experience with them is they don't sell junk. And I am sure they are class 10.9 tty bolts. I got mine from Houston and some of them had surface rust. 50 year old bolts NOS or not, are not necessarily a great choice either!

  8. #8
    Senior Member Parzival's Avatar
    Join Date:  Apr 2018

    Location:  Florida

    Posts:    326

    I totally agree that DeloreanGo is a good vender, I've spent tons of money with them. I'm just getting worried about the info I got about these head bolts.

    The exact criticism I got about these bolts.

    Quote Below
    "You posted a picture of aftermarket bolts in one of your posts. Is this what you intent to use or just posting as reference? Unfortunately the Ajusa bolts are wrong for this application for a number of reasons.

    The threads are roll formed onto the OD of the bolt- This results in a depth contact issue on the aluminum block threads while torque procedures are performed. You will have serious problems with getting gaskets to seat due to this.

    The bolt is below a nominal specification for use- If you look at the head of the bolt it is stamped 8.8. This gives it a Grade 8 rating. The factory fasteners are 10.9 which by comparison and taking the rockwell rating of 28 on the grade 8 versus the 40 on the 10.9 is nearly a 70,000 psi difference. End result is the bolt will stretch and loose tension resulting in head gasket leaks. I would strongly recommend investing in factory style bolts and or head studs."

    I know different vendors have differing opinions, as a mere DIYer I don't have the experience to know, and have to listen to all the advice I get, and weigh the differences out my self.
    I bought these from DeloreanGo based on the assumption that they sell parts that work. I was all set to use these bolts, but then I got the above advice.
    I just want the car to work, for preferably a long time.

  9. #9
    www.delorean.eu
    Join Date:  Jul 2011

    Location:  The Netherlands

    Posts:    72

    My VIN:    11626

    rock solid Ajusa

    We use the ajusa bold for years with turbo and blower setups. Never fail, rock solid and if you tight it up right, the are perfect.
    I rebuild every year lots of stock engine's, and special projects. There not one sign tht the bold are weak or bad. 100% first hand.

    Ed Uding
    www.delorean.eu

    Quote Originally Posted by Parzival View Post
    I totally agree that DeloreanGo is a good vender, I've spent tons of money with them. I'm just getting worried about the info I got about these head bolts.




    The exact criticism I got about these bolts.

    Quote Below
    "You posted a picture of aftermarket bolts in one of your posts. Is this what you intent to use or just posting as reference? Unfortunately the Ajusa bolts are wrong for this application for a number of reasons.

    The threads are roll formed onto the OD of the bolt- This results in a depth contact issue on the aluminum block threads while torque procedures are performed. You will have serious problems with getting gaskets to seat due to this.

    The bolt is below a nominal specification for use- If you look at the head of the bolt it is stamped 8.8. This gives it a Grade 8 rating. The factory fasteners are 10.9 which by comparison and taking the rockwell rating of 28 on the grade 8 versus the 40 on the 10.9 is nearly a 70,000 psi difference. End result is the bolt will stretch and loose tension resulting in head gasket leaks. I would strongly recommend investing in factory style bolts and or head studs."

    I know different vendors have differing opinions, as a mere DIYer I don't have the experience to know, and have to listen to all the advice I get, and weigh the differences out my self.
    I bought these from DeloreanGo based on the assumption that they sell parts that work. I was all set to use these bolts, but then I got the above advice.
    I just want the car to work, for preferably a long time.

  10. #10
    Senior Member Parzival's Avatar
    Join Date:  Apr 2018

    Location:  Florida

    Posts:    326

    Quote Originally Posted by ed uding View Post
    We use the ajusa bold for years with turbo and blower setups. Never fail, rock solid and if you tight it up right, the are perfect.
    I rebuild every year lots of stock engine's, and special projects. There not one sign tht the bold are weak or bad. 100% first hand.

    Ed Uding
    www.delorean.eu
    Thank you!


    Sent from my iPhone using Tapatalk

Page 1 of 5 1 2 3 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •