Is there a thread covering the HO conversion start to finish?
Plan to use E7 heads (I shop @ Pick-n-Pull), Is there a "best" donor vehicle? I have heard that GT40 heads were used on Merc Mountaineers. If its true, what years? After looking at the flow chart thread the GT's would seem to be a better choice.
Short block is bored 40 over with flat top pistons... I have heard that valve clearance can be an issue. I want as much cam as possible. Any recommendations?
Any pitfalls to look out for while doing this conversion?
I know just enough about all this to be dangerous so I would really appreciate some divine guidance here.
e7 heads will be your best bet because the gt-40's can need special headers. Also you wouldn't want to go much above stock mustang spec cams or you could get clearance problems. also I think most heads need the dished pistons as apposed to the tbird/cougar flat tops. Check out http://www.coolcats.net under the tech section.
The GT40's use standard 5.0 headers.The GT40-P heads need the special headers.The E-7 heads can be easily found on any fuel injected 5.0 pickups (Ford,of course).Probably cheaper to get them from a truck than a Stang,even though they are the same thing.People seem to think that the Stang parts are worth more.I'd be really careful with the GT40 heads and flattop pistons.If you use them,do a PTV clearance check to make sure everything is O.K.
Or I have a couple sets of E7's laying around.
FYI, there does exhist an early and late 1997 version of the GT40P heads and they changed them again in 1998. I have used the 1998 version in the past which were off of an Explorer. Mine had the thermactor bosses trimmed out of the exhaust port, not because they were very large but because I felt that they would cause a little bit of turbulence but not necessary to build power.
If you are installing a HO engine into a speed density car, you will of course need a different computer, repin the wire harness to work with the mass air system, don't forget to unplug the map sensor on the firewall because the mass air computer no longer uses it. Because you no longer use the thermactors in the heads your EGR is mostly useless and could be eliminated. This requires a diode trio assembly which I can forward to you. I got mine from a friend of mine on another forum. It turns the check engine light off on your dash and it worked great. The biggest difference between the speed density and the HO engines are the firing order and injector pulse order. They have to be changed because of the camshaft timing events being different. The nice part about it is that the cranks are the same part number and therefore would not need to be changed if you are planning on using the old speed density block.
Beware if you are using the speed density block! When I installed my "P" heads on that block I tested the pitson to valve clearances and my E303 camshaft with .498 gross lift with 1.6 rocker arms made contact, I have pictures of the clay i used. The reason for the contact results from the pistons that were used in my particular engine. The were flat tops without valve reliefs. I found it less time consuming to purchase a HO short block which can be seen in my picture post on this board. Header wise, the flowtech equal length shorties do not work well because they are tight on the number 4 cylinder and I burnt off a couple plug boots until I went with the MAC unequal lenght shorties. I used the 4048 Accel plug wires in a pinch because I had a set and they had 90 degree boots on the head end. That helped a lot. You will have to dimple the headers on the driver's side slightly to clear the steering shaft. I found that the stock valve springs used on the "P" heads needed to be upgraded because of the potential for valve float and binding, I used the Ford Motorsports springs that end in A50. They worked very well.
Here is what you need for a BASIC HO conversion. First off a mass air conversion is NOT required. It's easier and cheaper to do it speed density to start out using all stock Mustang stuff. Here's what you'll need...
HO Throttle Body, EGR Spacer, Intake
Stock HO Cam
E7 Heads
19# injectors
HO Headers, H Pipe and Custom cat back system
HO speed density EEC-IV
One of these Speed Density EEC-IV processors:
DA1 5.0 87 Mustang SD-SFI / Manual
DB1 5.0 87 Mustang SD-SFI / Manual
DC 5.0 Mustang SD-SFI / Auto
DE 5.0 Mustang SD-SFI / Auto
GJ1 5.0 Mustang
VH2 5.0 86 Mustang SD-SFI
VJ1 5.0 Mustang
VM1 5.0 86 Mustang SD-SFI / Manual
VP1 5.0 86 Mustang SD-SFI / Manual
VR1 5.0 86 Mustang SD-SFI / Manual
D9S 5.0 88 Mark VII SD-SFI
DX3 5.0 87 Mark VII
DY3 5.0 88 Mark VII
You'll need to change your IGNITION firing order to the HO (351W) firing order because of the cam swap. NO OTHER WIRING CHANGES ARE REQUIRED!
For more info I'd definitely visit Eric's Coolcats site.
Any mod could be put on by it self the only rule is CAM and ECM must be change together then put the SP wires in there correct places.
Required reading: http://www.coolcats.net/tech/advanced/ho_conversion.html
No wiring changes necessary if he runs speed densety...
MAP becomes a BARO sensor with no vacuum, but remains electrically connected...
Also the thermactor solenoids can be left in place and you'll never get a CEL(least I don't)...
I'd leave the EGR stuff in place (I did on my 88). The EGR system shuts off at WOT anyways and helps fuel economy so why not keep it. The 88 doesn't have any Thermactor stuff though. I did leave the solenoids in place though so the CE light wouldn't drive me nuts;) .
The thermactor and EGR are unrelated..
I know I'm just saying leave the EGR stuff on the car because it helps fuel economy and get ride of the thermactor stuff if you don't have to pass emissions.;)
Thanks for all the info:D
Went to Pick-n-Pull today and started drooling immediately. First car in the first Ford row was an 88 Linc H.O. Pulled the computer first and the code checked out (VL2). Now I'm foaming at the mouth and happily start to pull parts. I got everything I needed by 3 PM and headed home. Nothing better than coming home and checking out your plunder right? Thats when I checked the castings on the heads and I now have a nice set of E6 heads! The computer was as originally installed and the plenum had an H.O. Badge... I thought the two were not compatable. Could these be acceptable? If not I will take them back and get some E7's. Not to mention the plenum, MAF, MAP & TPS. The injectors are Tan so I guess they are O.K.
Headers: The Linc had what looked to be factory tubes. The H pipe is gone but the headers are there. Will they fit in my 87 or should I get a set of stock mustang headers?
Computers: I got the VL-2 out of the Linc and also found a DY3 in the trunk. Can these be tested or is the test when you fire it up?
'86 Stangs & '86/ '87 LSC Lincolns used E6 heads, same as on the SO 5.0... Those use the long reach 3/4" spark plugs, easy to spot 'em by pulling a plug... BTW those engines are rated at 200hp, mainly because of the heads...
Go back and get some E7's... E6's, which you already have on your car, suck.
The injectors should be orange for the HO 19lb.
Tan are the SO 14lb that your car already has.
The plenum should have an H.O. cast in it under where that plate sits. That will verify if it's correct. You could always measure the bore but it's easier to look for the cast.
Those headers will fit just fine. I've been running with them for nearly 4 years now.
Just don't forget that you'll need an h-pipe because of the location of the O2 sensors.
Seen lotsa HO inj that looked tan...
The whitish gray are the 14s used in the SO...
E6 headed 200Hp 5.0 HOs used 19lb inj, same as the 225Hp E7 headed versions... Generally the '86 HO used a std intake(and unique 58mm throttle body), look for a '87-up...
For the record, i did what I posted, the car averaged 28 miles per gallon from Dubuque to St. Paul Minnesota and Back with the 302, E303 camshaft, 76mm mass air meter, A9P computer, 30 lb/hr injectors, 190 lph Holley fuel pump, Holley Systemax II intake, Keith Craft CNC stage III ported Windsor Junior heads and a stock 89 GT block that does not have EGR or Thermactors. This was with a .80 overdrive and 3.73 final gears. The car scales at 3675 pounds with nine gallons of fuel and has run a best of 13.468 in the quarter mile @ 103 mph. The speed density from the 88 Mustang GT that we tried a the beginning did not like the E cam at all so we converted to mass air and it ran perfect.
No doubt, but IF he's going to run the flat top pistons there won't be clearance for a "E" cam... So speed densety will work fine...
Now if you want a good combo, get a set of Trick Flow heads and run 'em on flat tops like I do(with mas air of course)... Before my shiznit wore out, I've gone 13.11 @ 105.3... IF I'd have put more converter in it(only have a 2600) high 12's would have been easy...
It sure can!! With the right clearence check,Vinnie tried it,then got scared!!LOL.
HEY !!! Scared is such an unfriendly term,I prefer..........well,O.K.,scared (at the time,before I found the real problem)..I thought I had problems related to the E cam then found out I needed spacers under my roller rockers because with the milled heads the lifters were compressed to much.The E cam IS going back in.I still have to order gaskets to do the job.Probably in the nesxt few weeks if the weather holds out and I have a dry/warm place to work.I just ordered a set of the quality valve guide seals (not the umbrella type).As a matter of fact,I had enough PTV clearance with the E cam,and the heads were slightly milled.Crazy,but I swear it's true.I'm selling my extra parts to finance this,and gather parts for my a/c pieces and 5 speed swap.One piece at a time.
Sorry vinnie! didn't mean to set you off.I was just saying it can be done.Pretty soon I'll be checkin 512 lift at 10D with Flat tops.
What heads? And what cam?
When I installed the E303,I had ported E-6 heads with a 3 angle valve job on (not that the valve job made a difference).Now,E-7 heads.We did clay,and there was room enough for the cam to work fine.As a matter of fact,I drove it for a week until I figured out that it was the rockers,not the cam.I have faith that it'll be fine.I'll have a thread with all of the info,pics,and results.
Kitz,you didn't set me off.Without your constant harassment.....I mean "encouragement",I would've sold the cam and been done with it.
Sorry Vin :hick:
I was asking Kitz as I already knew your setup ;)
Still it is good to post it up for reference though.....
So what say you Kitz? What heads with a 512 lift cam and which cam for that matter?
It's E7's with the E cam and 1.7 rockers.I'm pretty sure it wont work but since I have my spare motor apart I can play with it.
I plan to buy a new cam and have been doing some looking. Lots of numbers out there. What are the specs on the stock Mustang cam?
Any benefit in paying for a Ford cam?