gt40p head users IN HERE!! deciding on cam!!

Discussion in '1994 - 1995 Specific Tech' started by 96darkhorse, May 26, 2004.

  1. here is my combo

    gt40p----- mild ehxaust port
    edel performer 5.0 intake
    rockers----waiting on cam to decide

    what cam is the best for this combo?? i dont want to go the custom route, id ont have 325 bucks for that.
    i dont care about emmission...heads dont have the thermactor hole....egr is non functional as well as the smog pump

    would you guys recommend to port and/or polish the performer intake??

    ohh yeah...what else would i need for the install?? i got the felpro engine gasket set down....would i need new push rods??? what lenght?size? what is everything i would need?? thanks

    also what hp/tq would this combo make?? mods are in sig
  2. I would consider the Crane 2031, Steeda #19, or the AFM B-21 (1.7's) B-31 (1.6's).... and those should work decent enough with our computers.. if you plan on a Tweecer, PMS, or custom chip, then you can probably get away with something more agressive, although the GT40p's do not need super high lift to perform....

    The intake should be more than enough for the heads..

    Pushrods will be dictated by cam selection, and rocker selection.

    With all the rest of the bolt-ons like, MAF, TB, LT's or shorties, full exhaust, ect... I would guess anywhere from 250-290rwhp, depending on how much of a freak your car is... and torque should be around 290-310... its really hard to guess without the rest of your combo...
  3. mods are in sig...i see your local

    out of those cams , which is the most aggressive??
    like i said , im not afraid of going aggresive :nice:
  4. I don't have the cam card infront of me... but I think the AFM cams have a max advertised lift of .542"/.542" ... the Crane cam has .513"/.529".. favoring the exhaust.. they are both considered blower cams, but seem to work good with our cars... I'm really not sure what the lift numbers are for the Steeda cam... I'm personally running the Crane 2031 cam, with GT40P's... and all the bolt ons.. On my last dyno run at Brothers performance I made 271rwhp 303tq running pretty rich (black smoke up top)... I'm re-dynoing on Saturday, and hoping for 285rwhp and 310tq, but we'll see..

    You should come out to our clubs dyno day on Saturday (29th) at some ricer shop in Upland called Hookups (yeah, sounds cheesy, but they have a dynojet)... They are charging us $40 for three pulls, with A/F reading... plus throwing in free hotdogs and sodas for the guys... You can find out all the info on our clubs board at, in the events section...

    P.S. if you sign up for our board, make an introductory post in the lounge before you post anywhere else.. its just something some of the guys are anal about...
  5. hey killer...i forgot to add that im putting 194/160 ferrea valves in them....i thougt you were a Wildhorse member at first.....i would love to meet with you guys this sat but i wont be able to :(

    anybody with bigger valves on their Ps??

    ive heard that a cam that favors the exhaust benefits these heads
  6. Talk with Greg from, or Tmoss.. and ask them about the larger valves... Greg says he can coax 320rwhp from a set of GT40ps, which I believe after seeing some of his port work. Tmoss on the other hand takes the low buck approach, and makes it work... he might have a little more data on how 1.90/1.60 valves work on the GT40ps...
  7. I would just stress the above mentioned fact that the P head flow goes flat at .400" lift, so if you want more power - look at duration, BUT that messes with your finicky 94-95 EEC. My heads have 1.94 and 1.54 valves in them but no port work - they are NMRA F/S prepped heads.
  8. I use a b-cam the lope, sound, and performance is amazing btw how much u spending on ur heads i bought mine new for 575 shipped and 550 max lift :nice:

  9. e-303

    I bought my 40p's also for 600.00 tri state cylinder head.I am running an e-303 cam, and the idle is mean sounding. I've had alot of good results with the e-cam, and that's the only reason I used it with my new setup. :nice:

  10. 1.85/1.55 actually...

    Unless something has changed that I'm unaware of.
  11. bigger than stock valves........duh

    "I would just stress the above mentioned fact that the P head flow goes flat at .400" lift, so if you want more power - look at duration, BUT that messes with your finicky 94-95 EEC. My heads have 1.94 and 1.54 valves in them but no port work - they are NMRA F/S prepped heads."

    yeah something has changed.....the size of his valves compared to stock.
  12. Yeah, the exhaust was a typo - I don't know the rules off the top of my head, but I bet the rules allow for some increase in valve size. These heads were run by Troy Carter (TMC on the boards) at Joliet in F/S before I bought them. Whatever the F/S class allows, that is what size is in there. I quickly put a mic on the intake valve and had over 1.90". I bought them from Steve Moberly - co-owner of the Evil Twin which races NMRA Real Street (used to be hot shoed by Ed Curtis). Steve was thinking of building a F/S motor but sold them to me when those plans fell through. I paid $1000 for the heads, Scorpion 1.6 rockers and NMRA prepped MAC "P" shorty headers as a package. I know the valve seat heights, valve/spring height assembly, etc, etc are professionally done for racing and that is a big part of why I bought them.
  13. I run the Steeda 19...its mild at .486 lift....Got some "irons" in this post... :nice:
    I wanted to do up some Gt40s...Got some Thumper stg2s instead...

    Tom...You fired that up yet????

  14. Yes I have, and I'm all smiles. Power is up and in the next month or so I'll be dyno tuning to get A/F and timing dialed in quick. The SD computer has adapted just like this was a stock motor - not one hic up!
  15. Glad to hear it...Nice when all goes well... :banana:
  16. ive heard 194/160 valves might be too big....with a 184/154 valve, would they need machine work( bigger valve seats)
  17. would a 185/155 valve be ok?? would it need machining??

  18. Yes, they will work. You will need a fresh valve job with new valves though so you will need some machine work reguardless.
  19. They are a nice set and to my knowledge are the only "P" heads to run in the 11's in FS competition. Coincidently I also used an Explorer intake on that car...but no port work. I'm very curious to see how well it performs on the dyno for you! Good Luck.
  20. Thanks Troy - results will be in my signature sooner or later. I ported the lower, but did not open the lower flange face much at all - the majority of the work was on the interior short side walls. The car has surprising low end torque and pulls very hard to red line - but that is SOTP and we all know how accurate that is.