Intake manifold spacers
 

Has anyone seen or tried these?

https://www.ebay.com/itm/Red-Aluminu....c100935.m2460

Copies of Crawford power blocks. I would just look for a used set of Crawfords. I use them combined with header and e85.

80% off?! :confused0068:
Oh lawdy
What's your opinion of them?

You have a dyno or any data?
Lots of data, testing, and dynos I’ve seen show they are not very good paired with E85. Its a one or the other. BPB is the poor mans E85 (or don't have access) A decent bump in power for NA non E85 users but not near what E85 does.

Poor mans E85?



in my experience, the power blocks on an untuned, stock fuel and header, moves the torque dip down a few hundred rpm and nets you a small increase in power at the top end.

With E85 and a header the torque dip isnt really there, but what it does now is addes to added mid range torque, you are increase the volumn inside the intake tract

is it worth it when you have an intake e85, header and custom tune? Eh hard to say. I would say save the 200 bucks or whatever

but the change in the torque dip on the stock tune stock gas car is nice. and coupled with the 4.3 diff makes for a snappy day above 4k rpm

It shifts the entire powerband down about 500rpm. so you have power sooner or more power throughout the entire curve below 6500 RPM but not more peak power, as in doing this you start losing and sacrifice top end around 6500+ RPM where E85 starts to really shine. With some tuning and tweaking you can get back some of the top end that is lost but not all of it and not all the way to redline.

That is why most people recommend not to use them together with E85 its one or the other with E85 being way better (IE poor mans E85). If you do use them together its not going to blow up your car or be a night and day difference of lack of power, so it still technically "works" just has no positive benefit used together.

https://www.ft86club.com/forums/showthread.php?t=62471

https://www.ft86club.com/forums/showthread.php?t=62007

A lot more threads discussing all of this already if you search. The gist is they do work but not well with E85 or with any FI.

I didn't make any performance claims. Not going to waste time dynoing a 200 hp car.

I put them on before going to e85 and haven't been motivated enough to remove them

Earliest pilots figured out the hard way that their carbs were icing up at altitude.

There was a video out there years ago of a 427 small block icing it's intake manifold during full power runs on an engine dyno. It was injected but the injectors were at the begginning of the runner vice the end. It was impressive.

note that those don't appear to have the small grounding tab that the crawford version has. that is specifically required to ground the injector control unit. i don't agree that the crawford version is worth almost $300, but it at least comes with a reputable company standing behind it.

They work as Tokyo's links show, but to get the most out of them (as with anything) you need to have a tune optimized for them. Shiv has some tips for optimizing the very top end - these give a noticable boost in the power curve between 5000 and 6500 rpm, and compress the torque dip (they basically compress the entire power curve). They are a good option for the crowd that doesn't want to go FI, limited to pump gas, and have done the other primary power adding mods. That said, you need to make sure to ground your relocated injector driver box, and also they need to be manufactured properly. If they are in any way not flat/don't mate to the heads/manifold well you can have problems with manifold vacuum leaks. I'd stick with the crawford ones - be patient and they pop up used on here for <$200 usually.


*edit* just realized I said "crowd doesn't want to go NA" meant to say "FI" lol