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how much work for a 390

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sapper8:
I have a 69 mustang grende. I had to strip it down(pulling engine and trans, rad,etc.). I am done with the suspension and brakes and someone gave me a 390  with trans. The car came with a blown 302. The qusetions I have are:

Do I need to beef up the suspension?
Do I need to change the motor mounts?
Do I have to move the Trans cross member?
Do I need special headers??

I know that this will be a pain to change over but I am up for the challenge. Any advise for this would be helpful

Thanks

NO IT NOT SO ALL:
The answer is YES to All. My 64.5 has a t-bird 429 in it. Major re-construction in engine bay. Move shock mounts, tranny crossmember, cut out and re-design firewall, remove inner fender skirts/ mud shields, etc., etc., etc.. Beef up everything; again, YES to All.

Topless_Horse:

--- Quote from: NO IT NOT SO ALL on August 30, 2014, 01:32:23 PM ---The answer is YES to All. My 64.5 has a t-bird 429 in it. Major re-construction in engine bay. Move shock mounts, tranny crossmember, cut out and re-design firewall, remove inner fender skirts/ mud shields, etc., etc., etc.. Beef up everything; again, YES to All.

--- End quote ---

Just to be clear, the 69 is much, much different than the 65 in terms of engine bay size and being able to accommodate larger engines.  The 69's came with 390's, 428's and 429's from the factory (the 65-66's did not).  You will not have to do any cutting in your 69 to fit the 390 but may have to change some of the mounts - depending on what transmission, etc. you end up using.  I'd suggest going with headers rather than the exhaust manifolds - several manufacturers make them (JBA, etc.).  You may also want to consider changing to a 9-inch differential (you probably have an 8-inch now) to ensure that you don't break something with the increased torque.  The 8-inch will probably work in the short term unless you race it or abuse it a lot.

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