351 Windsor Swap

Heads are D2OE, by the way. Heart-shaped 58cc chambers. The ports are little bigger than the 351w heads, and they have definitely been opened up a bit. Valves appear to be the same size at the 351 heads but I'm too tired to find out for sure right now...

 

SWEET!!! still tempted to do this with my comet. Post video when its running!

 

Test fitted the headers while the 302 short block is still in. Eh, wow, no. Not with the engine in, not even with it jacked up off the mounts. I think the only way will be to put the headers in before I lower the engine. And it's not even the towers that are in the way (yet).

Also, I finally verified the size of the dish in my pistons. 12cc. That means according to this, with a 4.060" bore, 3.5" stroke, 58.2cc heads, 12cc pistons, .0145" deck clearance, and .040" gasket thickness, I'll be running 10.09:1 compression.

 

Did you use stock Maverick engine mounts? These pics are from a 351w in a Maverick using those Summit G9031 headers. They aren't very encouraging... But the mounts weren't stock, so maybe this engine's positioned a little differently.

 

Yes I did use the stock frame and engine mounts from a 302. Those look like they sit much lower than mine did. The pipe on the #7 cylinder sat over the gear box if I remember. Like I said it was very close to a lot of stuff but they fit.

 

I am so glad you said that. The engine looks low to me too. You did use stock 302 engine and frame mounts for a Maverick, right?

Sorry for all the questions, the exhaust just has me nervous. It's the only "wild card" in this whole project that I don't feel like I've got 100% under control. There's just not a whole lot of good information out there, and man it's going to be really, really tight! I got to looking at it today and just thought it's going to take a miracle. But I feel a little better now.

So can you give me any installation tips? It looks to me like I'm going to need to put the headers in place before lowering the engine, then gently put it down and look at everything, pull it out and modify whatever needs to be modified. Driver's side firewall, you mentioned for instance.

I assume you notched your towers? Did you just do the standard notch that everybody does for spark plug access, or did you also cut out the middle hump/rib thing or anything else below the upper control arm mount?

Thanks for your help, it's greatly appreciated.


Thanks to everyone, really - the people I've been corresponding to in this thread and in PM's, you're what makes this Mav/Comet community great. I would not have attempted this without your help and soon this torque monster will be sending passengers to the chiropractor because of you.

 

Progress... Cam, timing set, lifters are installed. Started work on the heads. I experimented with a hand drill and a 1/2" bit, just to see what it would do, and believe it or not the head bolt holes I drilled came out perfectly straight and true with little effort. Basically the existing holes forced to me hold the drill straight or it would bind. I simply don't think it would be possible to cut these holes wrong with the equipment I've got. It's slow going, got to keep the bit oiled constantly, but I think this will work fine. My wire wheel is taking the deposits off the chambers and valves, cleaning up the gasket surface nicely. I think I'll need a cup brush to finish the job, but no big deal...

 

The headers in my Sprint look like the ones in the pics you posted. What i did to gain extra clearance with them was to put a 3/8" spacer between each motor mount where they bolt to the block (you will need 3/8" longer bolts) 4 of em and 4 spacers. This will get the headers away from the towers and steering box just enough that they wont touch anything...
I still have adequate hood clearance too boot.

 

By that I hope you mean the headers on your Sprint look like the ones in the pics used to. Good tip on the spacers. Do you know what model the Sprint's headers are? Or what mods had to be made to the firewall, towers, etc?

 

Headers are the G 9031s'
They still look like the above pictured ones
No mods on the firewall
Towers were beat with a BFH (wasent me man) Got it like that

 

Heres a couple shots of the towers/headers for you to peruse.
It was ugly when I got it...

 

Doesn't look so bad. This is really helpful, thanks. If I'm seeing this right, the areas where your headers are hammered look to be above the "standard notch line" which I'm calling about about 1-1.5" above the control arm mount. Was anything beaten up below that? The middle rib for instance, or the piece where the the engine mount bolts to?

 

I took a few pics for you...Hope they help. The middle rib (part of the structure the frame stand bolts to) was cut and flattened. The tubes are still in front of the UCA mount ing nuts...Raising the engine the 3/8"s allowed the headers to not touch them at all.
The dark shadow that looks like a header tube in the second pic showes how close the tube is to the bolt now. The rest should give you some idea of what your in for. If I can help with more pics (that I can take with the car on the ground) let me know...
There was no massaging (with a BFH) on the actual structure the frame stands bolt to.

 

Nice. So it looks like all of the modifications were made above the UCA bolts? I see the rib was flattened, but it looks like that's part that would be cut out if I did the tower notch that everyone does, right?

 

Yes, you lose that piece when you notch the towers.