GT40s.com
MK-I  MK-II  MK-III  MK-IV  GULF  MIRAGE  J-CAR  LOLA
GT40s.com
Home Forum Gallery Support GT40s.com  
Register FAQ Advertisers Search Today's Posts Mark Forums Read

Go Back   GT40s.com > >

Notices

GT40 Tech - Engines/Induction/Exhaust Motors and engine related - right here!

Reply
 
Thread Tools Display Modes
Old 8th May 2017, 03:22 PM   #21
LBCportagee
4 Tenths
United States
 
Join Date: May 2013
Location: Long Beach CA
Posts: 456
Re: Knock Knock

Consider upgrading to wider pushrods maybe (that will fit). I was amazed to see the difference in strength in wider pushrods vs thicker pushrods. Saw a video of pushrods at 9000 rpm and they looked like wet noodles...so I went with Manton series 5 rods on my car. They use a molten salt heat treating process and have a really high tensile strength. $250 well spent IMO.
LBCportagee is offline   Reply With Quote
Old 8th May 2017, 04:20 PM   #22
jac mac's Avatar
jac mac
I Have No Life
New Zealand
 
Join Date: Dec 2005
Location: Gore, NZ
Posts: 4,218
Re: Knock Knock

Is this 302w hyd cam?, wouldnt 9k capable pushrods be a little bit overkill. FWIW failure of posi loc's ( if that is what Robert would seem to have in his engine ) is not uncommon at the point where allen screw contacts end of rocker stud, due to overtightening or incorrect heat treat of the posiloc.
__________________
AMGT Rep Steel Mono from Plans, FE328 T44R
jac mac is offline   Reply With Quote
Old 9th May 2017, 08:30 AM   #23
RChianese's Avatar
RChianese
Silver Supporter
United States
 
Join Date: Jun 2012
Location: Frisco, Texas
GT40: GTD40
Posts: 57
Re: Knock Knock

Doug - Yes, the push rod is what I meant. I was able to find the head as it snapped off in one piece.

My hypothesis is that the set screw was over tightened. Comp Cams, and several other youtube videos, emphasize to only tighten these down to 25ft lbs. Seems that there is some underlying theme there!

I will backing all of them off and re-tightening them accordingly. I will also do a compression check on that cylinder to make sure the valve never hit the piston. However, I find that unlikely since there was no tension whatsoever on that valve when I discovered it. It was closed for sure.

Thanks
Robert
RChianese is offline   Reply With Quote
Reply

Tags
expensive, knock, start, swap, things


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 12:31 PM.