I'm lookin to buy a plenum. I always thought the Crawford Cast Plenum was the best plenum performance wise. But now with the introduction of the 1/2" Motordyne Spacer w/ iso therm upgrade to keep your plenum cool. Im beginning to think maybe the Motordyne Spacer with the iso therm upgrade give better performance numbers. Now i thought about gettin both, but i heard that putting both on is pointless because most of the hp gains comes from the first 1/8" space clearance of the plenum (dont know if thats true). So putting a 1/2" spacer or a crawford cast would be more than enough to produce max gains. So does anybody have any opinions on which is better? Now the price isn't really a problem, I just want to get the best plenum. Thanks in advance.

 

The thing is, until somebody dynos back to back installs of the md 1/2" spacer and the crawford plenum, nobody knows for sure. My GUESS is that you would get max gains with the crawford upper plenum and the motordyne isothermal gasket for your lower plenum. (It's a very small, thin thermal gasket that keeps the lower and upper plenums from absorbing as much engine heat.) But you're right, putting a spacer and a crawford plenum both would be pointless and your hood probably wouldn't close. Don't forget to buy the crawford strut bar, too.

 

Does anyone know if the entire Motordyne iso therm upgrade compatible with the crawford cast plenum or only the iso therm gasket is???

 

you can use the copper throttle body heater with any plenum i think.....

 

all the answers to your questions, even dyno comparisons btwn plenum and spacer, can be found on this site by using search function. happy hunting.

 

Alright i found tons of dyno info, but i still dont kno if the entire iso therm package including the copper tb heater is compatible with the Crawford Cast Plenum or only the iso therm gaskets will work with the Crawford Cast?? Does anybody know?? Thank You.

 

Hi GAaaAR,

All the Iso Thermal upgrades are fully compatible with all the cast plenums, plastic plenums, angled spacers, plastic spacers, SSV's and of course all the Motordyne products.

Iso Thermal is also fully compatible with the new and upcomming Motordyne REVUP mod "MREV".

For the most comprehensive comparative evaluation of plenum mods check out the next issue of Sport Z Magazine. PLENUM MOD SHOOT OUT!

The SZM article will be published and circulated very soon.

 

Thnx for the info. Im guessin the Revup Mod is only going to be for the 05 RevUp engines right??