Looking to get some heads and raise my compression ratio,would like to be in the 11.5:1-12.0:1 range. Car is a full bolt on,ms3 cam,150 shot and 4000 stall. The price is pretty close once u factor in new valve springs for the ai headwork. Just wanted to get opinions,thanks in advance

 

Either would work well, but you'd have more clearance with the Ai heads due to the smaller valves. One thing the Ai heads are known for is tip-in and throttle response. The heads are high velocity. I don't know what the runner size is on the PRC heads or how "explosive" they act when you mash the gas.

One other thing to consider: you have to send your heads off to be worked with Ai vs just buying outright with TSP. That's another factor to consider in case this is your DD. You'd be down as long as the heads are off the car. Ai has pretty good turn around times tho and a wide selection of springs to use.

 

Not a dd so not worried about downtime. Does anyone have firsthand experience with both heads in a similar setup? I would guess performance would probably be close? What type of cr could I achieve with the 5.3 heads?

 

Check out this thread:
https://ls1tech.com/forums/new-produ...l#post16976224

Also, keep in mind we can also port your stock castings as well!

 

Hey Jake, u got any dyno numbers on a setup like mine with w/ 241's ported by I guys? And what's the price on that?

 

*** u guys***

 

Id go with A.I. or TEA. no question.

 

Yeah I've nothing but good about them. Curious if they got any numbers on their porting though.

 

If you went TSP 5.3's, you can sell your 241's as well providing a little extra dough for the build. Just food for thought. The TSP 5.3's will be a better head IMO.

 

^Theres maybe $100 out of 241s. OP check these out. Only ones an A4 but you can get an idea. Only one of these is the HCR option as well. For the money, I dont think AI can be beat. Are dead set on keeping an MS3 in there?

https://ls1tech.com/forums/dynamomet...o-results.html

http://www.ls1gto.com/forums/showthread.php?t=441920

https://ls1tech.com/forums/dynamomet...m-results.html

 

There are so many factors that play a role in what a head flows and very few
TRUE back to back comparisons (same engine,cam,car,trans,tuner,dyno,STD
vs SAE,etc.,etc.). CNC programs come from multiple attempts by someone's
handy work to create a balanced head that flows air & fuel well. Valve sizes,
bowl approach, valve job and chamber unshrouding can all change the low,mid
and high lift flow numbers and too often people are dope on 300 plus max cfm.
The valve however spends only a brief amount of time at the .600 lift so it's
important for companies to have great low and mid lift numbers where the
valve will be for a majority of it's opening/closing cycle.
Either of your vendor choices will put you right on with your needs and the
5.3 casting is a good choice for you to max the compression without milling to
death causing PTV issues. AI does offer the HC (welded & CNC'd chamber)
option to do to your 241s for 11.5 comp but since you're running the Texas
Speed cam I'm sure they know exactly where your piston to valve clearance
will be with the PRC heads, gasket thickness choice, and so on.