Need some guidance on the hot side plan. 3" downpipe will squeeze around stock ac suitcase. Crossover pipe will hang below engine x member by 1.75", or 2-3" off the ground...yikes. Also thinking of putting the IC > rad > engine, inside the bay.



Looks like I can squeeze 3" downpipe around ac suitcase and have 1/2 clearance all the way around.



Planning on 2.25" crossover under t56. Will hang below engine x member 1.75". Worried that it might be to low.



Planning to leave condenser in stock place. Will mount IC then rad inside engine bay.

 

I'd want the IC in front of the condenser....delta T. I too would be worried about ground clearance with the crossover as you have it mocked.

 

if you're set on keeping the stock ac evaporator setup another option might be running forward facing manifolds which would give you more room for the downpipe and eliminate the problem with the crossover being too low

 

The crossover should be more forward, between the bellhousing and the trans. That will give you a little more space.

Andrew

 

Here is a video that may help you see the hot side plan issues:

 

True, I do plan on running e85 at some point.

 

I did move it forward some, gained a little bit.

Another thing I can consider is a spin tech frame clearance section that is 1.75-1.88" tall. Still might be too low:

https://spintechmufflers.com/frame-clearance-tube/

 

Yeah it looks like the crossover is a deal breaker. I will mock up some forward facing manifolds and see how it looks.

 

The crossover is not going to be any lower than if you had long tube headers with 3" collectors. Food for thought.

I wouldn't run the crossover in the front.

Andrew

 

Well.....some longtubes with 3" collectors would hang too low as well.... I think the issue is -- 1) how low is too low? 2) How do you stay above that? Many, as Andrew mentioned earlier, run in the 'high' space that often exist either in front of or just behind the bell housing. Others, run the crossover around the front of the engine. A simple heat shield can manage any thermal issues that might arise from any of those locations.

 

Excellent point. The old engine/headers did hang low and I never scraped.

Soooo proceed with the plan?

 

Yup, that's what I would do. You don't have any other real good options. I'd also ditch the AC suitcase and install that new, nifty cover that you got. You don't want to be hacking at the inner fender and snaking the downpipe around the suitcase.

Andrew

 

I put the car on the ground and here is the 2.25" pipe mocked up where the crossover would go. I have 3.75" clearance easy, maybe 4" of if I go tighter.

BTW, my old header was 3.5" off the ground and I did not scrape.

I've decided that this will be good enough for me. I'm going for it!

 

I did the same thing with my 66. Mine is about even with the crossmember after I shimmed the rear of the trans to get a decent driveline angle. I was going to run it under the bellhousing but that didnt gain much clearance over running it under the trans.

 

Thanks for the feedback. Tran is as high as it will go w/o driveshaft hitting the tunnel at front floor brace.

How much ground clearance do you have at the crossover?

 

Not sure of the clearance I will measure it when I work on the car tonight. Mine might be a little higher right now due to the lack of some body panels and interior.

 

The advantage to running a forward crossover, is it frees up more room for a downpipe. If your just going to run a 3 or 3.5" downpipe, it's not as big a deal. I don't know how much would fit around a stock ac setup either. A vintage air unit frees up a lot of room.

 

Too low IMHO. If you rub a speed bump with headers it smashes the primaries or grinds off the collectors and, oh well it looks shitty. If you pound that crossover with a speedbump it will probably break welds and cause leaks. And if its wrapped you'd never see them. Going around front creates its own issues but it's doable.

Forward a down manifold, passenger side.

 

Blacksix, that's a nice setup, but where is the gate/gates?

 

Can you share your acc setup?

My old engine header collector was 3.5" off the ground and I did not scrape. Proposed crossover will be 3.75-4".

Update video on the plan: