Are (half-inch) intake plenum spacers worth it, and do they tend to help more low, mid, or high RPM? My memory is people were seeing small but real gains on them. Curious if opinions have changed over the years. $110 and I can do it in my garage doesn't seem too bad.
are intake spacers worth it?
- Thread starter YELOSNK
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I never really saw Cobra guys making power with them. They seemed popular with the Mach guys, but I'm not sure I'd call 10rwhp worth it. That could easily be a run to run difference on the dyno.
Something else to remember is if you have the EGR you'll have to modify the tube. And by the time you add in the gaskets it's around 3/4" taller. I don't remember if that would get into the hood or not.
IMO, waste of money.
Something else to remember is if you have the EGR you'll have to modify the tube. And by the time you add in the gaskets it's around 3/4" taller. I don't remember if that would get into the hood or not.
IMO, waste of money.
It was really only worth it on the Mach 1 because it raised the shaker. Power-wise, never felt a thing. And yes, the egr tube is a bitch to get hooked back up. I'd pass.
I did it on my cobra and saw 20 rear wheel torque and 5 rwhp gain. I left the egr hooked to the upper intake lid when I did mine and was able to slide the spacer in and get it bolted down. Now that my car is FI I thought about taking it off to see if maybe it would improve my idle. I noticed like a dirt/oil substance on the back of it this past summer. Idk.
interesting. seems like there's some differing opinions on this one. I did see a post on another forum where someone says they did 6 passes with and 6 w/o and saw a similar 5rwhp gain at peak. is your spacer 1/2" or 3/8"?
Thanks all for the responses.
His results aren't typical. There's a thread somewhere on here about it.
this. someone did a back to back or two equivalent modded cars and it wasnt a noteworthy difference
I sent you a PM about this
1/2
This has been gone over quite a few times over the years.
Basically intake spacers don’t make enough to rule out the margin of error on a dyno on 99/01. We are talking 1-2 rwhp here on stock/bolt on NA cars. Size really doesn’t matter either. 03/04 Mach 1’s are a different story but the heads and cams are different on those.
There are plenty of threads.
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Basically intake spacers don’t make enough to rule out the margin of error on a dyno on 99/01. We are talking 1-2 rwhp here on stock/bolt on NA cars. Size really doesn’t matter either. 03/04 Mach 1’s are a different story but the heads and cams are different on those.
There are plenty of threads.
Sent from my iPhone using svtperformance.com
Yea I’ve seen those as well. I did mine last after I did about every bolt on possible so idk if that’s why mine responded so well or not. The hp numbers could’ve been varying conditions but the torque jumped substantially and I noticed a little different sound from the engine while driving.
Any little gain for the N/As for the price of the spacers is not a bad deal. I ended up not running mine because of the EGR tube and in California you have to pass a visual inspection. I would have removed my EGR valve if not having to have a visual. I will sell my brand new one for a large discounted price that includes shipping. PM me if interested
I've looked at a number of threads (including the 16-pager linked in this thread) and I don't think I've seen someone post a back-to-back which shows no difference. Might have just missed it, though, as 90% are opinions or, like that 16-pager, a few people attacking each other.
The most reliable I've seen, where they actually did a few pulls both with and without, showed ~5whp peak gain on a bolt-ons car. Not much, but not terrible for the cost, given the labor should be doable in the garage with a beer.
honestly I'm at least, if not more, interested in now it impacts (if at all) low vs. mid vs high. even there, though, there doesn't seem to be a consistent narrative.
anyways, thanks all for the input!
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Honestly, I would put the money aside and either look for a ported intake or have yours ported. You'll see more of a gain from that than a spacer.
My only experience is anecdotal. I had a big bore set up in my 01 that eventually I put an F1A on. I tried a 3/8" spacer that was given to me with the stock intake and nothing felt different. I switched to a ported stock length intake and the engine gained a few hundred RPM. Before the intake it would lay over around 6100-6200rpm. After the intake it pulled to 6500-6600. I might have been able to rev it higher, but I didn't want to chance.
That combo was never put on a dyno, but I did my own tuning on the street. So I was able to watch the air flow increase through logs.
My only experience is anecdotal. I had a big bore set up in my 01 that eventually I put an F1A on. I tried a 3/8" spacer that was given to me with the stock intake and nothing felt different. I switched to a ported stock length intake and the engine gained a few hundred RPM. Before the intake it would lay over around 6100-6200rpm. After the intake it pulled to 6500-6600. I might have been able to rev it higher, but I didn't want to chance.
That combo was never put on a dyno, but I did my own tuning on the street. So I was able to watch the air flow increase through logs.
I've thought about porting but may just wait and also do a 9.5-10" short runner. Although if I can find someone trustworthy local to do just porting for a good price it might be worth it.
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