yes, i would prefer quality lifters.
and we recondition lifters for ourselves
but your question was on bronze guides.
not using bronze guides gives us one less thing to be concerned about.
-----Original Message-----
From: Ted Schumacher <tedtsimx@bright.net>
To: n197tr4 <n197tr4@cs.com>; FOT <FOT@autox.team.net>
Sent: Thu, Nov 3, 2011 12:41 pm
Subject: Re: [Fot] Zinc Additive. now use of BRONZE GUIDES
Joe,the engine shop is correct. Bronze guides should always be
clearanced. But that is an indictment on whom ever did the head, not
the guides themselves. For the past several years, lifter have been a
serious issue. We used to bring in Spit/TR6/etc lifters, #143552 by the
hundered through theearly-mid'90's. Then they started to go down hill.
We have Rockwell checked new lifters that have gone all the way down to
a 28. 39 - 41 is fairly common.Minimum hardness should be at least 55 or
greater. There have been several fixes tried including using different
size lifters such as Ford. Problem here is the lifter bore on a
Spit/TR6engine is at a 4.5 degree slant so boring it out correctly is
not easy(or inexpensive). The most consistent lifter supply we have
found is reconditioning used lifters. They Rockwell test each lifter and
if it is a minimum of 55 and can be saved, it is reconditioned. We
rebuild a lot of heads and engines and new engine start-up procedure is
still the major factor in the equation.Ted
On 11/3/2011 9:12 AM, n197tr4@cs.com wrote:
> Sent: Thu, Nov 3, 2011 8:25 am
> Subject: Re: [Fot] Zinc Additive. now use of BRONZE GUIDES
>
>
> FROM TED SCHUMACHER:
>
> Why dont you use bronze guides? How did you come to this decision?
>
>
> Ted,
>
> I discussed with highly regarded performance engine shop.
> Whenever they encounter bronze guides they clearance them.
> If it doesnt get done, there is a danger of seizing.....which can get very
> hard on lifters and cams.
>
> Some engineering folks tell me that cast iron guides provide superior
> performance.
> And say that bronze cause more heat/friction/wear......................
>
> This and observing various failures over the years caused me change.
> Certainly it is the right decision for me.
>
> Others may have a different conclusion and I would invite them to discuss
on
> this list.
>
> I have long suspected that there have been a lot of failures attributed to
> 'soft lifters', and faulty cams, when it may have been caused by seizing of
> valves or severe drag in bronze guides.
>
> Thanks for asking Ted. It seems like it is an important subject for this
> list.
>
> Joe Alexander
>
>
>
>
>
>
>
> -----Original Message-----
> From: tedsimx<tedsimx@bright.net>
> To: n197tr4<n197tr4@cs.com>
> Sent: Wed, Nov 2, 2011 8:54 pm
> Subject: Re: [Fot] Zinc Additive.
>
>
> Why don't you use bronze guides? How did you come to this decision? Ted
>
>
> Connected by DROID on Verizon Wireless
>
>
> -----Original message-----
>
> From: n197tr4@cs.com
> To: lang@isis.mit.edu, JAR7U@hscmail.mcc.virginia.edu
> Cc: fot@autox.team.net
> Sent: Wed, Nov 2, 2011 21:16:11 GMT+00:00
> Subject: [Fot] Zinc Additive.
>
>
> Use of bronze guides is or can be an issue here.
>
> ESPECIALLY those not properly clearanced.
>
> It ALSO seems that cast iron guides are 'slippery' while bronze can create
> added friction and wear.
>
> We dont use bronze guides anymore.
> _______________________________________________
> fot@autox.team.net
>
> http://www.fot-racing.com
>
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>
>
--
Ted Schumacher
tedtsimx@bright.net
http://www.tsimportedautomotive.com
108 S. Jefferson St.
Pandora, Ohio, USA 45877
Fax: 419.384.3272 (24 Hrs.)
Phone: 800.543.6648 (US& Canada)
Tech/ Gen. Information/ Worldwide: 419.384.3022
_______________________________________________
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