I need some information on how i cant get more performance out of my inline6?

the car is a 1970 mustang coupe inline6 3-speed manual.

 

I always say start with lower rear gearing if your not overly concerned with MPG..

We put 4.10 gears in the 66 pre engine swap and the car was a kick to drive.

Performance mods to the engine will help of course, but I am of the opinion that the factory gearing was just too damn low on the 6 Mustangs. I thinkFord's goal was MPG on these cars and the gearing was pretty steep for the little 6.

Prior to the rear swap I dreaded having to let the clutch out. talk about a slow burn...

 

+1 on the gearing. then you can get some i6 headers from mustangs plus and a better carb. then you can save up about 4-5k for a 302 crate motor.

 

its had a 5 bolt conversoin i think its a 8 inch rear end not sure on the gearing. ive heard these engines have ****ty manifolds

 

http://www.ausfordparts.com/2502v.html

 

if it's had a 5lug conversion and 8" rear I wouldn't bother with an inline6.
I'm the other way round. driving an 289 on a 6banger rear axle ...

but in regards of the gearing. I believe that the 6bangers and 289s mostly had 3.2:1 ratio. at least mine has.
I can't drive 60mph without having the engine rev over 3000rpms, which is quite annoying.
Would that not make it far worse to gear it 4:1 or similar ?

btw happy new year JMD ;-)

Kalli

 

Most 8" rears came with 2.80's or 3.00's. I have 3.25's in my 67 and I'm turning about 3300 @ 75mph with short tires.

Anyway, back to the original post... I'm glad someone is actually trying to work with an I6 They have a lot of potential, and there are plenty of performance parts out there for them now.

http://www.cliffordperformance.net
http://www.fordsix.com

Headers are a great upgrade (after gears). The factory log intake sucks...but it's cast into the head. To make some real power, swap in a 250 head with an aftermarket intake, or even an entire aluminum head, along with a cam.

I've seen sixes that will run circles around factory 289's. They're lighter, which makes for better handling, and cube for cube they make more torque than a V8.

 

Happy new year to you as well Kalli, I have been wondering about you, haven't seen you here in a while! glad to see you here.

Yea the lower gears will cause the engine to wrap up a little tighter. I know this is an issue for lots of folks but I like it!

The best possible fix for this is the low gearing combined with an overdrive tranny,this can be expensive, but it would put the cruising RPMs back where they were, give or take a little.

IDK, a junkyardoverdrivetrans from a later V-6 Mustang would probably work pretty welland the price wouldn't be that bad..

I think I have heard that the 250 ci 6s used the SBF bolt patern on the clutch housing, if so, this would be an easy swap other than the cable clutch or hyd clutch conversion.

 

I knew a guy I bought a 61 falcon a few years back.
They were putting in f150 300 6 cyl engines and a paxton on those suckers man those things were fast.

 

well biggest thing is the money for now (cant swap to a v8) the car also has to get around its going to be a daily driver.

how can i find out what gears i have in it?

i thought about going with a new manifold and a 4 barrel carb. along with these heads http://classicinlines.com/products.asp?cat=53
also thinking of a new ignition system and exhaust.