cszymanski82

If I've got an E303 cam and 1.7 Rockers will the springs on the GT40P heads be alright or do I need to replace them with stiffer springs?

Joel5.0

Nope...... need to replace them, the stock ones will bind, and will not support the E-303 profile.

my77stang

^ +1, etc, etc, etc

samsonhusky

are the springs different on a 85 mustang than the gt-40 and gt-40p because my brother has a 85 mustang with the stock heads and springs and is using e303 cam with no trouble, and i was wanting to use the same cam on my 85 with gt-40 heads of of a 96 explorer with stock springs

mjr46

now if you put the matched valve springs to that cam then your brother would be able to reach full rpm potential.....you and he may think it's fine ......but I gaurantee at the upper rpm's valve flutter is occuring which is reducing power output....been there done that.....cam swap = valvetrain upgrade...if it were fine to do such and max potential then John Force would do the same as you

Joel5.0

If you mean "with no trouble" as in "it hasn't broken any spring yet"...... he has been lucky. It's not an issue of the E, B, Stg 1, or whatever cam you end up using increase in valve lift, you need springs with a higher pressure rate to be able to control those valves...... stock valve springs = stock cam, barely.

my77stang

wait wait wait......

first of all, an E303 could break a spring at any time.

second of all, he said an E303 with a 1.7 rocker. that means even MORE lift.

third of all (?!?!) why in the hell would you want to use an alphabet cam anyways

cszymanski82

I bought a shortblock (built by Proline racing in Woodstock, GA) off someone that had the E303 already installed. I don't plan on taking the car to the track, it's going in a convertible.

Can anyone recomend a good but cheap set of upgraded springs? What about these?
http://cgi.ebay.com/ebaymotors/COMP-...spagenameZWDVW

samsonhusky

i have the e303 cam it came with the motor don't know if they changed the springs are not i'm putting the gt-40 heads on with this cam what springs would work best with the e303 cam on gt-40 heads

cszymanski82

OR THESE
http://store.summitracing.com/partde...p;autoview=sku