[DeTomaso] CHI 4V heads question

Larry Finch fresnofinches at aol.com
Sun May 17 19:22:43 EDT 2020


Thanks Julian,

As usual you introduce valid considerations. 

The rubber isolators are used and were selected from my collection of about eight and are dimensionally comparable to what I removed. 

The pedestals are new, but I just checked and they are the same height as the older ones. I’ve never heard of two different heights but one never knows. 

There is Line-X bedliner underneath the pedestals with a measured thickness of about .125 inch.  My gut feeling has been this is too small an amount to have such a notable effect, but????,

2511 was on a frame alignment machine during repairs but while I am unsure how much attention was paid to the rear of the chassis, I would assume dimensional checks were made and nothing I have observed in the last year points to any chassis deformation. I have not yet had the car in for tire alignment. 

My second engine builder (don’t ask, there was also builder #3)  and I had the opportunity to compare the iron heads to the new aluminum heads. Not knowing the milling history of the iron heads made precise comparison measurements difficult but we both had the impression that the header bolt holes might have been raised a small amount. 

I did encounter a definite issue when using those heads with the blue thunder Pantera-specific intake, and I know of another owner who used these heads (intake unknown) and encountered the same need for spacers on both the engine block china walls —



So that experience and the gut feeling from the comparison has prompted this query on the CHI heads.

I just finished talking with the previously mentioned owner and found his header collector flange to exhaust pipe gasket is the round, fiber donut style. The mechanic who did the wrenching on his installation made no mention of alignment problems similar to what I am finding. 

So now I am wondering if perhaps there is much more adjustment range with the donut style gaskets? I have no personal experience and would love to hear others’ thoughts on this —-

Could changing over to the donut style of gasket come with a greater alignment flexibility and overcome and solve my current misalignment issue?

Larry


Sent from me using a magic, handheld electronic gizmo. 

> On May 17, 2020, at 3:27 PM, Julian Kift <julian_kift at hotmail.com> wrote:
> 
> Larry,
> 
> I am almost certain the CHI 4V heads are a standard exhaust port and bolt location. Could anything else have changed during your rebuild e.g. new engine mounts rubbers, thicker head gasket, painted engine bay (below motor mounts) etc.?
> 
> It may be a dumb question, but assume it was on a chassis alignment rack during collision repairs, perhaps it wasn't straight to start with?
> 
> I have CHI 4V, C302B and A3 heads here, but no stock iron heads to compare to if I were to measure exhaust header bolt location.
> 
> Julian
> 
>  
> From: DeTomaso <detomaso-bounces at server.detomasolist.com> on behalf of Larry Finch via DeTomaso <detomaso at server.detomasolist.com>
> Sent: Sunday, May 17, 2020 2:51 PM
> To: Email List Address For Posting <detomaso at server.detomasolist.com>
> Subject: Re: [DeTomaso] CHI 4V heads question
>  
> Mike,
> 
> So your experience with the same heads showed no major header flange to exhaust flange gap, but you apparently chose the Remflex gaskets because they could overcome a ....small.... gap you encountered?
> 
> I have used their gaskets at both ends of my headers for some years now and this gap is beyond their sealing capabilities. 
> 
> If only this issue ...could... be solved so easily ......
> 
> Thanks,
> 
> Larry 
> 
> 
> 
> Sent from me using a magic, handheld electronic gizmo. 
> 
> > On May 17, 2020, at 2:00 PM, Mike Drew <MikeLDrew at aol.com> wrote:
> > 
> > Larry,
> > 
> > I wound up using a pair of Remflex gaskets on each side (collector gaskets) for that reason. I think it came about when switched from iron to CHI 4V heads. 
> > 
> > That solution worked fine for me.  They have a lot of ‘crush’ capability and can be useful for alleviating such concerns. I also use their header gaskets exclusively. 
> > 
> > Mike
> > 
> > Sent from my iPad
> > 
> >> On May 17, 2020, at 13:54, Larry Finch via DeTomaso <detomaso at server.detomasolist.com> wrote:
> >> 
> >> All,
> >> 
> >> This is a question for any owner that has installed the CHI 4V aluminum cylinder heads on a Cleveland in their pantera. 
> >> 
> >> During collision repairs I had a 404 ci stroker Cleveland built for 2511 and used the CHI 4V heads. 
> >> 
> >> I did not change the GTS exhaust pipes/mufflers nor the GTS headers supplied by Dennis.
> >> 
> >> But something has changed and the exhaust pipe will no longer correctly mate with the header flanges. With the mufflers as close to the body as possible, there is a gap at the top of the header flanges of about 3 sixteenths of an inch. Even removing the ZF side mounts and letting the transaxle rest on the rear crossmember, there is still a header flange gap. 
> >> 
> >> I’m thinking the exhaust ports on these heads may have a raised header bolt pattern and this is the source of the misalignment.
> >> 
> >> Has anyone else found similar misalignment problems after installing these heads?
> >> 
> >> Thanks,
> >> 
> >> Larry 
> >> 
> >> Sent from me using a magic, handheld electronic gizmo. 
> >> _______________________________________________
> >> 
> >> 
> >> Detomaso Email List is not managed by POCA
> >> Posted emails must not exceed 1.5 Megabytes
> >> DeTomaso mailing list
> >> DeTomaso at server.detomasolist.com
> >> http://server.detomasolist.com/mailman/listinfo/detomaso
> >> 
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> >> 
> >> Members who post to this list grant license to the list to forward any message posted here to all past, current, or future members of the list. They also grant the list owner permission to maintain an archive or approve the archiving of list messages.
> > 
> 
> _______________________________________________
> 
> 
> Detomaso Email List is not managed by POCA
> Posted emails must not exceed 1.5 Megabytes
> DeTomaso mailing list
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-------------- next part --------------
   Thanks Julian,

   As usual you introduce valid considerations.

   The rubber isolators are used and were selected from my collection of
   about eight and are dimensionally comparable to what I removed.

   The pedestals are new, but I just checked and they are the same height
   as the older ones. I've never heard of two different heights but one
   never knows.
   There is Line-X bedliner underneath the pedestals with a measured
   thickness of about .125 inch.  My gut feeling has been this is too
   small an amount to have such a notable effect, but????,

   2511 was on a frame alignment machine during repairs but while I am
   unsure how much attention was paid to the rear of the chassis, I would
   assume dimensional checks were made and nothing I have observed in the
   last year points to any chassis deformation. I have not yet had the car
   in for tire alignment.

   My second engine builder (don't ask, there was also builder #3)  and I
   had the opportunity to compare the iron heads to the new aluminum
   heads. Not knowing the milling history of the iron heads made precise
   comparison measurements difficult but we both had the impression that
   the header bolt holes might have been raised a small amount.

   I did encounter a definite issue when using those heads with the blue
   thunder Pantera-specific intake, and I know of another owner who used
   these heads (intake unknown) and encountered the same need for spacers
   on both the engine block china walls --

   image1.jpeg

   So that experience and the gut feeling from the comparison has prompted
   this query on the CHI heads.

   I just finished talking with the previously mentioned owner and found
   his header collector flange to exhaust pipe gasket is the round, fiber
   donut style. The mechanic who did the wrenching on his installation
   made no mention of alignment problems similar to what I am finding.

   So now I am wondering if perhaps there is much more adjustment range
   with the donut style gaskets? I have no personal experience and would
   love to hear others' thoughts on this ---

   Could changing over to the donut style of gasket come with a greater
   alignment flexibility and overcome and solve my current misalignment
   issue?

   Larry

   Sent from me using a magic, handheld electronic gizmo.
   On May 17, 2020, at 3:27 PM, Julian Kift <[1]julian_kift at hotmail.com>
   wrote:

   Larry,

   I am almost certain the CHI 4V heads are a standard exhaust port and
   bolt location. Could anything else have changed during your rebuild
   e.g. new engine mounts rubbers, thicker head gasket, painted engine bay
   (below motor mounts) etc.?

   It may be a dumb question, but assume it was on a chassis alignment
   rack during collision repairs, perhaps it wasn't straight to start
   with?

   I have CHI 4V, C302B and A3 heads here, but no stock iron heads to
   compare to if I were to measure exhaust header bolt location.

   Julian
     __________________________________________________________________

   From: DeTomaso <[2]detomaso-bounces at server.detomasolist.com> on behalf
   of Larry Finch via DeTomaso <[3]detomaso at server.detomasolist.com>
   Sent: Sunday, May 17, 2020 2:51 PM
   To: Email List Address For Posting
   <[4]detomaso at server.detomasolist.com>
   Subject: Re: [DeTomaso] CHI 4V heads question

   Mike,
   So your experience with the same heads showed no major header flange to
   exhaust flange gap, but you apparently chose the Remflex gaskets
   because they could overcome a ....small.... gap you encountered?
   I have used their gaskets at both ends of my headers for some years now
   and this gap is beyond their sealing capabilities.
   If only this issue ...could... be solved so easily ......
   Thanks,
   Larry
   Sent from me using a magic, handheld electronic gizmo.
   > On May 17, 2020, at 2:00 PM, Mike Drew <[5]MikeLDrew at aol.com> wrote:
   >
   > Larry,
   >
   > I wound up using a pair of Remflex gaskets on each side (collector
   gaskets) for that reason. I think it came about when switched from iron
   to CHI 4V heads.
   >
   > That solution worked fine for me.  They have a lot of `crush'
   capability and can be useful for alleviating such concerns. I also use
   their header gaskets exclusively.
   >
   > Mike
   >
   > Sent from my iPad
   >
   >> On May 17, 2020, at 13:54, Larry Finch via DeTomaso
   <[6]detomaso at server.detomasolist.com> wrote:
   >>
   >> All,
   >>
   >> This is a question for any owner that has installed the CHI 4V
   aluminum cylinder heads on a Cleveland in their pantera.
   >>
   >> During collision repairs I had a 404 ci stroker Cleveland built for
   2511 and used the CHI 4V heads.
   >>
   >> I did not change the GTS exhaust pipes/mufflers nor the GTS headers
   supplied by Dennis.
   >>
   >> But something has changed and the exhaust pipe will no longer
   correctly mate with the header flanges. With the mufflers as close to
   the body as possible, there is a gap at the top of the header flanges
   of about 3 sixteenths of an inch. Even removing the ZF side mounts and
   letting the transaxle rest on the rear crossmember, there is still a
   header flange gap.
   >>
   >> I'm thinking the exhaust ports on these heads may have a raised
   header bolt pattern and this is the source of the misalignment.
   >>
   >> Has anyone else found similar misalignment problems after installing
   these heads?
   >>
   >> Thanks,
   >>
   >> Larry
   >>
   >> Sent from me using a magic, handheld electronic gizmo.
   >> _______________________________________________
   >>
   >>
   >> Detomaso Email List is not managed by POCA
   >> Posted emails must not exceed 1.5 Megabytes
   >> DeTomaso mailing list
   >> [7]DeTomaso at server.detomasolist.com
   >> [8]http://server.detomasolist.com/mailman/listinfo/detomaso
   >>
   >> To manage your subscription (change email address, unsubscribe,
   etc.) use the links above.
   >>
   >> Members who post to this list grant license to the list to forward
   any message posted here to all past, current, or future members of the
   list. They also grant the list owner permission to maintain an archive
   or approve the archiving of list messages.
   >
   _______________________________________________
   Detomaso Email List is not managed by POCA
   Posted emails must not exceed 1.5 Megabytes
   DeTomaso mailing list
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   To manage your subscription (change email address, unsubscribe, etc.)
   use the links above.
   Members who post to this list grant license to the list to forward any
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   list. They also grant the list owner permission to maintain an archive
   or approve the archiving of list messages.

References

   1. mailto:julian_kift at hotmail.com
   2. mailto:detomaso-bounces at server.detomasolist.com
   3. mailto:detomaso at server.detomasolist.com
   4. mailto:detomaso at server.detomasolist.com
   5. mailto:MikeLDrew at aol.com
   6. mailto:detomaso at server.detomasolist.com
   7. mailto:DeTomaso at server.detomasolist.com
   8. http://server.detomasolist.com/mailman/listinfo/detomaso
   9. mailto:DeTomaso at server.detomasolist.com
  10. http://server.detomasolist.com/mailman/listinfo/detomaso
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