CHI heads and hedders question - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

70 Mach 1 · 01-06-2007, 20:14

Was wondering if anyone on here had a 70 Mach 1 with 9.2 deck Cleveland with CHI heads. I would love to put these heads on my motor but am concerned that with the raised exhaust port my hedders might have clearance issues. Thanks for any and all replies.

Chris

falcon coupe · 01-07-2007, 01:48

It's really no different to running iron 4v's, i have swapped from iron 4v to CHI and will be using the same pacemaker 4 into 1's.

70 Mach 1 · 01-07-2007, 06:23

Thanks for the reply. Hedder fitment is VERY tight on my setup and I read on CHI's website that they angle cut the face on the exhaust port which is going to rotate the hedders in towards the motor. I run a powerglide transmission with a JW Ultrabell bellhousing and had to do some trimming to get the hedders on. I had more room when I had a C-4 in the car. I really want to run a set of their 258cc heads but want to make sure I am not creating a nightmare for myself.

Chris

jim1320 · 01-07-2007, 16:19

Headers 70 mach 1 393 cu cleveland with Chi 3v heads and intake 225cc 3v. the header work from my 4v heads hooker 1 7/8 tubes . Did not see big improvment with the heads unport out of box about same my 4v heads. Looking for some help? The heads are off the engine now. Like to get thems port it. pricing on a port job go 900.00 to 1800.00 or just try clean up myself? How much more hp can you get? Best time to date 10.51 et 126mph 3260 lbs Jim

70 Mach 1 · 01-08-2007, 07:43

Jim I am not sure where you are located, but give Brad West at West Cylinder Heads a call (1-870-230-3476). He is located in Arkansas and does excellent work. I have currently have a set of closed chambered 4v heads he did for me using titanium valves that flow 341@.700 intake and 225@.700 exhaust. They have been a best of 10.02@132 at 3405 lbs. We have 3 race cars and he does all of our head work.

What transmission are you running in your car? Sounds like we are running a very similar combination. Please let Brad know that I sent you if you give him a call. Thanks for the information about the hedders.

Chris Minchew

TruBlu351 · 01-09-2007, 00:53

I just fitted some 1 7/8 headers with 3.5" collectors on my Aussie Falcon with CHI 225's.

It was a tight fit on the drivers side, but just squeezed in. Just put the gearbox in and I have about 1/3" clearance under the crossmember on one side and the other is just touching. Looks like I'll have to get that collector bent down a little, so no real big problem. This is why I didn't want to go getting them all Jet-hot coated and then have to play around afterwards.

That's with a TKO box and I am running a 1" spacer under the gearbox to raise it up, so if it was all stock, they would fit perfect. But I'm sure where's it's at now is the same as a C4/Toploader so that's one spot to look out for.

I think Brenx had to bend his down too? He's running a Powerglide.

brenx · 01-09-2007, 13:07

Bending headers down with CHI's is usually a 2V 4-1 issue. 4V headers shouldn't have this problem. I know a few people that had 4V headers and just swapped heads etc. Never had a problem with the headers at all.

The reason the 2V ones have an issue and the 4V ones don't? The 4V ones hang lower.

jim1320 · 01-09-2007, 17:48

1970 Mach 1 runs at the track on street nite . mufflers and slicks trans. is c4 with ati 8 inch stall 4700 in the car with a 4.56 rear , 393 cleveland 3.85 stoke ,6inch chev. with srp flat top pistons 206069 . camshaft is i think is crane 252 262 dur. 727 727 lift and 108 centerline. rpm about 6700 and going thur 7300 rpm. try to get Chi head to help on the car . Jim

70 Mach 1 · 01-09-2007, 17:51

Thanks for the replies guys, feeling more confident about making the swap. Has anyone tried the 258cc runner head yet or heard anything about them good or bad?

Thanks

Chris

70 Mach 1 · 01-09-2007, 18:07

Jim have you tried a higher shift point yet? My heads are alittle bigger with a 247cc intake runner and will slow down quite a bit if I shift at anything less than 7200. I have the same rotating assembly, .264 .267 @ .050 duration and .713 intake and .696 exhaust 108 centerline in at 106. Have the motor out right now for freshen up and heads are going back to Brad for some touch up work on the epoxy, maybe we can find just enough to put the car into the 9.90's. It almost sounds to me like your convertor is alittle loose, we are crossing the line at the same rpm but with a 6 mile per hour difference. Just some food for thought.

Chris