Problem with new valvesprings/retainers CRANE

ncontt · 03-20-2013, 01:02 PM

Ok guys, I've had these springs/retainers etc on my sons motor for AWHILE (still on engine stand) I had the machine shop do the work on the heads and install the new springs. The heads are GT40s from an Explorer.

Problem is this:
All of the retainers on the exhaust valvesprings hit on the bottom of the rockers (stock crane "cobra" rockers, I believe I got from someone on here but don't remember) before the tip of the rocker hits the top of the valvestem.

I noticed all the exhaust springs have a shim under the springs so I went and got a valvespring tool (which works pretty well actually) and took the shim out and put the locks back in and it is still the same. I will update with some pictures as soon I can post them from my phone.

Just not sure what to do with this as this is above my "paygrade"....I am pretty much just waiting on resolving this issue to put the motor/trans (needs a VB and convertor) into my son's Fairmont....

ncontt · 03-20-2013, 01:34 PM

Model number on the retainers

Stock Cobra rockers

Difference in spring height (bad angle but you get the idea)

Difference in retainers

These are the beehive springs that were recommended to me at Summit, brand new, never run, the valves "far as I know" are the stock ones 11/32" stems, as you can tell the intake and exhaust have different retainers The tops of the valvestems are all even, it's the tops of the springs that are NOT and are causing the interference with the rockers....

Any help would be appreciated....

Brad

QWKSNKE · 03-20-2013, 03:05 PM

Is there a difference in the locks?

ncontt · 03-20-2013, 03:16 PM

I think....Let me check, but ya if you just look at them they look different to me! I'll check and see if I can find the spring (kit) on summit's site...

93cobra1928 · 03-20-2013, 03:50 PM

The GT-40 heads have different stem heights for the exhaust and intake valves, why I don't know (beancounter), you can put lash caps on the short ones and that should solve your problem.

QWKSNKE · 03-20-2013, 07:45 PM

Quote:

Originally Posted by 93cobra1928

The GT-40 heads have different stem heights for the exhaust and intake valves, why I don't know (beancounter), you can put lash caps on the short ones and that should solve your problem.

Was this specific to the P heads? I don't recall my cobra heads being that way

1Quik85GT · 03-21-2013, 12:24 AM

Quote:

Originally Posted by QWKSNKE

Was this specific to the P heads? I don't recall my cobra heads being that way

I used to run gt40 heads back in the day, and I measured my valves and they were the same length... and I wouldnt advise to NOT running lash caps...thats a worse disaster waiting to happen.. They do have a diff style of lash caps that you can run! are you sure the installed heights are the same?

QWKSNKE · 03-21-2013, 07:06 AM

I think the locks are the problem. I always use the same locks on all valves on the heads I have run

ncontt · 03-21-2013, 07:48 AM

after doing some research, it is because the groove in the exhaust valve is lower than the groove on the intake valves. Valves are stock valves. Install height now is 1.99" (top of the head where spring sits, to the top of the spring/bottom of retainer) I "believe" they call for an installed height of 1.94" therefor requiring that the spring come down another .o50" which would give me the room I need on the rockers....I "think"

ncontt · 03-21-2013, 08:01 AM

they have offset keepers that are either + .050" or - .050" so I'm thinking I need the -.050" s

03-20-2013, 01:02 PM	#1
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	Problem with new valvesprings/retainers CRANE Ok guys, I've had these springs/retainers etc on my sons motor for AWHILE (still on engine stand) I had the machine shop do the work on the heads and install the new springs. The heads are GT40s from an Explorer. Problem is this: All of the retainers on the exhaust valvesprings hit on the bottom of the rockers (stock crane "cobra" rockers, I believe I got from someone on here but don't remember) before the tip of the rocker hits the top of the valvestem. I noticed all the exhaust springs have a shim under the springs so I went and got a valvespring tool (which works pretty well actually) and took the shim out and put the locks back in and it is still the same. I will update with some pictures as soon I can post them from my phone. Just not sure what to do with this as this is above my "paygrade"....I am pretty much just waiting on resolving this issue to put the motor/trans (needs a VB and convertor) into my son's Fairmont.... __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~

03-20-2013, 01:34 PM	#2
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	Model number on the retainers Stock Cobra rockers Difference in spring height (bad angle but you get the idea) Difference in retainers These are the beehive springs that were recommended to me at Summit, brand new, never run, the valves "far as I know" are the stock ones 11/32" stems, as you can tell the intake and exhaust have different retainers The tops of the valvestems are all even, it's the tops of the springs that are NOT and are causing the interference with the rockers.... Any help would be appreciated.... Brad __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Last edited by ncontt; 03-20-2013 at 01:36 PM. Reason: added picture

03-20-2013, 03:05 PM	#3
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	Is there a difference in the locks? __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

03-20-2013, 03:16 PM	#4
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	I think....Let me check, but ya if you just look at them they look different to me! I'll check and see if I can find the spring (kit) on summit's site... __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~

03-20-2013, 03:50 PM	#5
93cobra1928 Dazed and Confused Join Date: Mar 2009 Location: Northport, Al Posts: 778	The GT-40 heads have different stem heights for the exhaust and intake valves, why I don't know (beancounter), you can put lash caps on the short ones and that should solve your problem. __________________ Proud owner of 93 Cobra #1928 306ci Forged flat tops, Windsor Sr iron heads, FMS X-303 cam, OE Cobra upper and lower, 65mm tb, 70mm maf, 24lb injectors, BBK shorties, Summit H-pipe and Flo-bastards

03-21-2013, 07:06 AM	#8
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	I think the locks are the problem. I always use the same locks on all valves on the heads I have run __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

03-21-2013, 07:48 AM	#9
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	after doing some research, it is because the groove in the exhaust valve is lower than the groove on the intake valves. Valves are stock valves. Install height now is 1.99" (top of the head where spring sits, to the top of the spring/bottom of retainer) I "believe" they call for an installed height of 1.94" therefor requiring that the spring come down another .o50" which would give me the room I need on the rockers....I "think" __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~

03-21-2013, 08:01 AM	#10
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	they have offset keepers that are either + .050" or - .050" so I'm thinking I need the -.050" s __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~