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EFI swap - GT40P heads w/ stock explorer exhaust manifolds

RVH

Jr. Member
Joined
Apr 10, 2007
Messages
121
Loc.
Fort Collins, CO
All-

Has anybody attempted to use the stock explorer exhaust manifolds with an Explorer EFI engine swap which has the P heads? I know these manifolds do not look the best and some could argue look restrictive ... but has anybody tried to use them in their swap or confirmed if they will work or not? It seems most of the lower mile explorer engines I find are after 1997 1/2 so they have the P heads, so I am just trying to fully account for investing in the exhaust solution if I go with an explorer engine that has the P heads.

I am sure several have already gone through this exercise when trying to find the right donor Explorer engine, so any lessons learned, insights, or conclusions others have reached would be greatly appreciated. I know of the fuel rail change in '98, but I have already accounted for that one.

Rob
 
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lars

Contributor
Been here awhile
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Jun 29, 2001
Messages
3,030
Loc.
NorCal flatlands
All-

Has anybody attempted to use the stock explorer exhaust manifolds with an Explorer EFI engine swap which has the P heads? I know these manifolds do not look the best and some could argue look restrictive ... but has anybody tried to use them in their swap or confirmed if they will work or not? It seems most of the lower mile explorer engines I find are after 1997 1/2 so they have the P heads, so I am just trying to fully account for investing in the exhaust solution if I go with an explorer engine that has the P heads.

I am sure several have already gone through this exercise when trying to find the right donor Explorer engine, so any lessons learned, insights, or conclusions others have reached would be greatly appreciated. I know of the fuel rail change in '98, but I have already accounted for that one.

Rob

I have seen one Bronco running a p-head Explorer 5.0 with the OEM tubular manifolds. The owner did tell me that he had to do some cut/hack/weld to make them fit, but fit they did. He had a manual transmission with stock clutch linkage, and managed to clear all that stuff. I only saw the end result, not the mods in progress, so I don't know exactly what mods were made. But it can be done.
 

904Bronco

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Bronco Guru
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Sep 28, 2004
Messages
5,743
Loc.
San Martin, CA
When I bought my 75, it had a 97 explorer motor with a Carb in it. The PO welded up the EGR tube hole in the pass exh manifold. At the time, it had a C6 in it and the stock Exhaust manifolds worked in that configuration. I remember that it had dual exhaust and it was tight on the pass side frame rail.
 

kbldawg

Bronco Guru
Joined
Jun 26, 2007
Messages
1,492
Loc.
Marshall, AR
Tito and I both have done it. We both run standard trannies. He has a zf, mine is an np435.

ive got something about it in my build thread, ill look it up.
 

Tito

CB Fire Starter
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Jan 29, 2006
Messages
10,781
Loc.
Bakersfield, CA
Tito and I both have done it. We both run standard trannies. He has a zf, mine is an np435.

ive got something about it in my build thread, ill look it up.

But we are running the Bronco manifolds not the explorers, I think he is looking to see if anyone is running those. I have a set that I plan to try on my next build but havent mocked them up yet.
 
OP
OP
RVH

RVH

Jr. Member
Joined
Apr 10, 2007
Messages
121
Loc.
Fort Collins, CO
But we are running the Bronco manifolds not the explorers, I think he is looking to see if anyone is running those. I have a set that I plan to try on my next build but havent mocked them up yet.

Yeah - I am looking to better understand either -

1 - The effort/cost to use the explorer exhaust manifold
2 - Invest in the proper headers for the P heads
3 - Wait to find a motor with the non P heads and moderate mileage

I know you guys ground down the existing manifolds, but I just hate to take that much meat off of the iron manifolds.

Rob
 

lars

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Messages
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NorCal flatlands
One factoid worth noting regarding BCB's headers is that they are made from 14 gage tubing. That makes them nearly as heavy & thick walled as the stock iron manifolds. They'll likely last a long time.
 
OP
OP
RVH

RVH

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Joined
Apr 10, 2007
Messages
121
Loc.
Fort Collins, CO
Lars - Good to know on the BCB headers. I have not actually seen a pair, but I figured they would be excellent grade and quality. I just hate to spend more on headers then it will cost me for the whole explorer motor ....

Rob
 

Roadburner

Full Member
Joined
Mar 14, 2008
Messages
168
I'm using the L&L long tube headers from Jeff's on my P heads. Need to use Taylor wires w/135 deg boot. Have a 4 speed toploader in mine. Been running them for about 7 years with no problems.
 

benwehmann

New Member
Joined
Nov 3, 2011
Messages
21
Loc.
Madison, WI
But we are running the Bronco manifolds not the explorers, I think he is looking to see if anyone is running those. I have a set that I plan to try on my next build but havent mocked them up yet.

I just want to make sure I am understanding what you are saying correctly, you are running or were at some point running stock Bronco exhaust manifolds on the GT40P heads? And everything clears just fine? I was reading somewhere else that they had to do some heavy grinding to get the spark plugs to fit but it doesn't sound like that is the case.

The reason I am asking is that I am running the stock 302 in my 73 Bronco and one of the exhaust valves is burnt. A friend of mine is parting out a 98 Explorer and told me if I pull the heads they are mine for free. I figured why not rebuild the GT40P's than the stock heads but didn't want to do it if I was going to have to buy headers to make it work.
 

garberz

Bronco Influencer
Joined
Jun 24, 2007
Messages
6,856
Loc.
Conejo Valley, Ca.
I'm running the stock Explorer exhaust manifolds on my original 302. The manifolds are from a 98' with "P" heads. I'm almost ready to swap in the Explorer 5.0. I'm running a C4 trans. I think there would be clearance issues on the drivers side if you had clutch linkage.

Mark
 

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Ranchtruck

Sr. Member
Joined
Feb 7, 2008
Messages
766
They are also awful manifolds from a flow perspective. Massive restrictions where they crushed the tube to fit around bolt heads ect. They were meant to fit the v8 in a v6 engine bay and not catch fire, not for any performance.

If you can get the heads for free, try to get the whole engine and front accessory drive/alternator/fan ect too. You will need a different cam gear on your distributor to match the roller cam in the engine and a late model flywheel, but that's it.

Oh, and potentially have to do a work around for the clutch equalizer pivot, but that's easy enough to do too.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,275
Hey benwhemann, welcome to CB!
Good call dredging up this old thread too. Now nobody can accuse you of not searching first! ;D
Well, some here might still, but you can just show them this and tell them to get out with their bad attitudes!

I don't think they were saying that all this stuff "clears just fine" running the stock EB manifolds. Just that it can be done without extreme drama.
It might also depend on the year of the casting, as there were likely some minor variations between EB manifolds during the 12 year run. I've seen some where they plug wire cleared, but was almost touching. Others that wouldn't clear until at least some grinding was done.
Same with most headers. Either they just barely fit, or some dimpling of a tube or two required and away you go. Some new ones from BroncoHut might be just the ticket.

Good luck whichever way you go.

Paul
 

surfer-b

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Bronco Guru
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Sep 7, 2006
Messages
2,971
I'm running the 2000 Explorer with the C4 and factory manifolds, no clearance issues at all. the first 2 are the Pass side, the last is Driver
 

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WorkerBee

Full Member
Joined
Aug 22, 2011
Messages
224
Loc.
Northern CA
I am using the stock bronco cast iron manifolds. I took one look at the GT40P manifolds that came with my motor and tossed them aside. Even if they were the best flowing manifolds in the world I would never use them based on the fact that they look horrible. It's kind of like a well dressed woman wearing those weird water socks. functional yes, good looking no.

Grinding the cast manifolds wasn't really that bad and it's still plenty thick in that area. I have had zero issues running them but I used high heat socks around the boots. Here's a picture of a little grinding that I did.
 

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RnrdTheFox

Sr. Member
Joined
Dec 4, 2005
Messages
727
Loc.
Superior, CO
I'm running the 2000 Explorer with the C4 and factory manifolds, no clearance issues at all. the first 2 are the Pass side, the last is Driver

Sorry for the Hijack. Where did you get your heat shield for the floor? Did you pull it form the junkyard or order it online? I need the samething on my passenger side and haven't taken the time to track something down. Did you see a noticable difference? Thanks.
 

Mark in Memphis

Full Member
Joined
Apr 29, 2004
Messages
181
I'm using the L&L long tube headers from Jeff's on my P heads. Need to use Taylor wires w/135 deg boot. Have a 4 speed toploader in mine. Been running them for about 7 years with no problems.

Roadburner,

Which L&L Headers are you running? I'm looking at JBG website and I see 302 headers for 87-96 Broncos and for Bronco II's but I don't see a set for Early Broncos. Do you have a part number?

Mark
 
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