I know this has been posted ad nauseum, but I was cleaning my upper and lower intake manifolds this weekend and noticed something very strange.
First, I have an 98 EO SVT #580 something I think.
When I removed the upper to clean, I decided to take a few measurements to try and port match the upper to the lower. I noticed the uppers were all about 2-3 mm smaller than the lowers on both the short and long runner ports. I don't have the exact measurements, but the lowers were closer in size to the 99-00 measurements. I thought this was very interesting as I knew the upper was supposed to be slightly smaller than the opening of the lower, but a 2-3 mm diff. on all of the upper ports was a big suprise.
So, now I'm thinking, if the upper and lower are designed to gradually taper for more velocity into the heads, why is there such a difference between the upper and lower.
The intake air is forced through the much smaller upper, then expands at the beginning of the lower, only to be compressed again at the bottom of the lower.
How is this supposed to be efficient?
dont know how it works well, but that is why so many port match to get ride of that little lip that is there
One reason might be that the E0's were only single-pass extrude honed. The second pass done on E1's and later does open up the runners a fair bit.
The large lower does sound weird, however.
-Lance
Originally posted by Lance Kinley:
One reason might be that the E0's were only single-pass extrude honed. The second pass done on E1's and later does open up the runners a fair bit.
Incorrect!
Discussed thoroughly when the Extrude Hone Group Buy came about.
To summarize, all SVT UIMs were passed the same number of times - same flow for 98, 99 and 00.
Confirmed by Extrude Hone and Terry Haines. I also took measurements of all runners between a 98 UIM and a 00 UIM and there was almost no difference between the two in the measurements.
SVTPETE, I think I want to have sex with your car.
Back on topic: I beleive the extra extrude hone process mentioned by SVT in their brochures had to do with the secondary ports on the heads and the larger LIM ports, and as proven in the other thread, had nothing to do with the UIM.
It IS known that there is a larger SVT LIM out there, found in late SVT's and some of the 00 cougars as well that have 34/35mm ports compared to 32/33mm ports IIRC.
I know I have managed to grab up a 34/35mm LIM.
I'll have to measure my LIM the next time I have it out, hopefully soon to put some bigger injectors in.. I have one of the last 75 CSVT's ever built so I'd imagine I'd have the larger, if it was ever made.
Mark
Originally posted by Y2KSVT:
if it was ever made.
It was, I have it installed and verified the measurements. I personally bought mine off of car-part.com which labeled it as off of a '01 cougar. I had the yard verify the port size before I bought it, and verified again once I received it. 
Yes, I am aware of the thread proving that all of the UIM have the same basic measurements, and don't want to bring that up again. The interesting thing is the size of the lowers. They measure much closer to the larger returnless size. Is it possible My car was assembled right when they were switching over to the 98.5 spec and got a larger lower manifold with return style fuel rail. It would be strange if I did, but knowing Ford, it is possible. Please help if possible.
But, I don't mind having the larger lower at all.
Did you buy your car brand new? If not, are you sure the previous owner didn't have work done to it? Could have very well installed it themselves. Who knows
Mark
No, I bought it back in 2000. I don't think the previous owner did anything to the car because they would have probably port matched the upper to match the lower as well as possible and the upper did not look like anyone did anything to it at all.
Originally posted by Bike2112:
... The interesting thing is the size of the lowers. They measure much closer to the larger returnless size...
I posted a month or so ago about the same thing. I checked my LIM after cleaning and got the following measurements:
Upper LIM Hole
Primary: 33.45mm
Secondary: 34.95mm
Difference: 1.50mm
Lower LIM Hole
Primary: 32.64mm
Secondary: 34.05mm
Difference: 1.41mm
*Measuring procedure: Two measurements that agreed per hole, at ~90 degree intervals. Averaged all six of each type of hole to arrive at the above numbers. Measured with digital calipers.
So yeah, I'm still curious about the existence -- or not -- of the larger LIM, as the replies I received from my previous post were inconclusive, IMHO. (No offense to anyone who replied to it. 
) Does anyone else have actual measured data from their larger LIM to compare with these numbers?
Originally posted by Bike2112:
...First, I have an 98 EO SVT #580 something I think...
...Is it possible My car was assembled right when they were switching over to the 98.5 spec...
My car was built in May of 1997, so it was a very early model. If your car is #580, then it was built before mine, as mine is build #786. That would put it well before the 98.5 model year changeover.
Originally posted by Bike2112:
...I noticed the uppers were all about 2-3 mm smaller than the lowers on both the short and long runner ports...
Yeah, mine had an ugly difference in port size between the UIM/LIM as well. The LIM-to-head-port interface was pretty mismatched as well. Almost looked like the heads were skewed a degree or two from the centerline of the engine. Some port matching is definately in order there.
Marty
Originally posted by rkneeshaw3.0:
SVTPETE, I think I want to have sex with your car.
Damn, I thought I loved my car...nver thought to have sex with it! 
Thanks though. It's coming along slowly... 
Originally posted by SVT PETE:
Originally posted by Lance Kinley:
One reason might be that the E0's were only single-pass extrude honed. The second pass done on E1's and later does open up the runners a fair bit.
Incorrect!
Discussed thoroughly when the Extrude Hone Group Buy came about.
To summarize, all SVT UIMs were passed the same number of times - same flow for 98, 99 and 00.
Confirmed by Extrude Hone and Terry Haines. I also took measurements of all runners between a 98 UIM and a 00 UIM and there was almost no difference between the two in the measurements.
Ok, so the whole 'dual hone' bit a while back was a crock?
-Lance
i think it means that both primaries and secondary ports go done, maybe??
I memory serves correctly, I believe the dual extrude honing on the later SVT's took place in the heads instead of the UIM. Someone step in here if I am incorrect.
My main inquiry is the fact that my LIM is closer to the later SVT LIM in port size and I have an EO 98. I just thought it was interesting to have such a difference between the port size of the UIM vs. LIM. A little time with the dremmel will take care of this.
On another note, when I had the UIM off, there was no evidence of EH at all as there were several small casting bumps inside the intake. It was not very smooth at all from the factory.
Well the "literature" says more extrude honing on the UIM and more aggressive extrude honing on both the primary and secondary head ports. (verses just "normal"
EH on the secondary ports)
bet it was smoother then mine, i can take some pics later to prove it, mine looks like concrete almost, very bump inside
Originally posted by DemonSVT:
Well the "literature" says more extrude honing on the UIM and more aggressive extrude honing on both the primary and secondary head ports. (verses just "normal" EH on the secondary ports)
That is what I thought too. I wish I knew the answer. But judging from the look of the inner walls on the UIM, it does not "appear" to have been EH. Operative word here is definately appear. This could be very misleading due to the amount of buildup inside the runners.
The plan: take it off again (ran out of daylight to do a thorough cleaning) and really spend some time on smoothing and port matching the UIM to the LIM as best as possible.
On another note, does it seem odd to have such large openings on the LIM. It's a nice problem to have of course, but I wonder how much turbulence is actually being generated by the difference of the UIM vs. LIM.
Thoughts?
Just realized something, could the literature referring to dual EH on the primary and secondary head ports be where the confusion is? Cold some of us be confusing dual EH of the UIM and LIM with DH of the primary and secondary head ports? They are different as the UIM and LIM are not actually part of the heads but the intake itself.
Originally posted by gearhead98:
bet it was smoother then mine, i can take some pics later to prove it, mine looks like concrete almost, very bump inside
Sounds just like mine.
My SVT UIM was a LOT smoother than the SE UIM that I had on the car during the recent group buy. How to describe it. Say the SE UIM is like concrete, very bumpy. The SVT UIM would be like concrete in your basement or garage floor. Still not perfect but MUCH smoother. Hope that helps a little.
I'm not sure if there were any pictures taken of the differences inside the passages, the only ones I can recall were of the different diameters.
Originally posted by EvlBill:
My SVT UIM was a LOT smoother than the SE UIM that I had on the car during the recent group buy. How to describe it. Say the SE UIM is like concrete, very bumpy. The SVT UIM would be like concrete in your basement or garage floor. Still not perfect but MUCH smoother. Hope that helps a little.
I'm not sure if there were any pictures taken of the differences inside the passages, the only ones I can recall were of the different diameters.
Mine is in the middle. Not rough, but not smooth.
Originally posted by Lance Kinley:
Originally posted by SVT PETE:
Originally posted by Lance Kinley:
One reason might be that the E0's were only single-pass extrude honed. The second pass done on E1's and later does open up the runners a fair bit.
Incorrect!
Discussed thoroughly when the Extrude Hone Group Buy came about.
To summarize, all SVT UIMs were passed the same number of times - same flow for 98, 99 and 00.
Confirmed by Extrude Hone and Terry Haines. I also took measurements of all runners between a 98 UIM and a 00 UIM and there was almost no difference between the two in the measurements.
Ok, so the whole 'dual hone' bit a while back was a crock?
-Lance
As discussed in this thread...
Rick Miller of Extrude Hone - all SVT UIMs are the same.
Rick Miller Voicemail
Terry Haines -
The 5 extra horsepower is a result of:
- later heads being ported, early not
- later heads have a revised/added intake port hone
- .25 compression ratio increase in later years
Originally posted by SVT PETE:
Rick Miller of Extrude Hone - all SVT UIMs are the same.
Rick Miller Voicemail
Guys,
I'm starting to run low on storage space and will be deleting that file soon. If you want to save it, I recommend doing it soon.