View Full Version : New project

03-01-2007, 08:46 PM
Long :)
My next project for the Cobra is building a 331 stroker with 185 AFR heads... I got a Scat 331 stroker kit, crank, forged KB pistons & rods ( I believe it is the 9000 series kit) for a very very good price (over 1/2 off). The kit was assembled but not started. I got a block at the machine shop now and will take the rotating assembly with flywheel & balancer (both 28 oz) to get it all balanced. I've had the AFR 185 heads for almost 9 months waiting, didn't think they would fit the stock short block pistons. Gonna put them to good use now. I already got some Clevite hard bearings and will be getting the other paripnaila the comming weeks. I'm looking for a Cobra lower intake to send to TMoss for porting, keep the Cobra intake. I'm still undecided on the cam. The local Mustang shop recomended a E 303 cam, they said they don't like Crane cams? But I'm have not rules out the Crane 2031 cobra cam (I believe it is a reduced base cam requiring different push rods). Need something emissions legal that will not mess with the picky 94\95 computer. The pistons are flat tops with relief and depending on where the piston is in the block with the 61 CC heads, I'm looking at compression ratio of around 9.2 to 9.7, will know when I check it. Might have to go with thicker Cometic head gaskets, .060" over the .045" to bring the compression ratio down closer to 9.



I'm looking to make over 300 rwhp, and hoping for over 325 NA. Then add the Powerdyne supercharger with the 9 lb pully after the motor has been broke in. No more boost with the compression ratio & the Powerdyne is maxed out, impeller speed. The powerdyne added 95 rwhp to the stock motor, from 255 rwhp to 345 rwhp. I have a set of 36 lb injectors with matching MAF meter, but will need a GT computer or have my Cobra computer tuned for the 36'ers. Not sure who or when I will get it dyno tuned with a chip, might run it safe (will be checked on a dyno) for a little while with no tune, while I save for a dyno tune. Funds are tight.
I'll get the long block completed, then remove the stock 131k engine, then storing the original long block. I'm hoping to get it all done by FFW in early May.
My goal is over 400 rwhp.

What do you think? Think I wil make my goal?
Opions? Comments. On cam.

03-01-2007, 09:28 PM
I think you can make your goal. My AFR 185 heads added 53 rwhp and 43 ft lbs of torque. I have 303 hp at the rear wheels and 333 rwtq naturally aspirated and my car is the stock bore and stroke. Adding the charger should bump you over the 400 mark pretty easily I would think especially with a stroked 302. I'd try to get the compression as low as you can so you can add some more boost besides 9 lbs. I would at least want 12 lbs if I could get it set that way. I'm am definitely going to do one of two scenarios for my 94 Coupe, either a 331 like you have or a 392, stroked 351 W, and I won't be charging either one of them. :D

03-02-2007, 08:14 AM
Awesome! :thumbsup: If you need an extra pair of hands on the weekends, let me know. I love working on pushrod motors.

03-02-2007, 09:04 AM
Hey Tony, the Powerdyne supercharger is pretty much maxed out with the 9 lb pully, impeller speed of 40,000 rpms, so unless I change to a vortec, that is all the boost I will have. I'm wanting around 9:1 compression ratio for good low to mid hp till the supercharger kicks in. Here is a good article about compression vs boost: http://www.motorsportsdigest.com/forced2.htm .

Thanks Larry, I have to get the block back from the machine shop, then I'll build up the long block.

I'm aiming a little low for the HP numbers & hoping for the best.
Still working on which cam.

03-02-2007, 09:30 AM
I have the stock cam in my cobra with the stock rockers, same afr heads, eagle 331 assembly and stock pully s-trim vortech with power pipe (10-12lb), race girdle prepped block by Paul's Automotive Engineering, Cincy. It makes right a 500rwhp at 6000rpm on a dynojet. The idle is set at darn near a 1000rpm with a 94-95 gt computer and superchips custom tune to keep the idle from surging. I would recommend an Anderson pms if you want a bigger cam. I would have one if they weren't $950.

03-02-2007, 10:11 AM
I have to get the block back from the machine shop, then I'll build up the long block. Do you have access to an engine stand for when you're assembling? If not, let me know.

03-02-2007, 12:10 PM
Thanks Larry, I have a engine stand.

Eric, I would love to have the Anderson PMS, been looking on Ebay. The 94\95's are hard to come by used. You have surging issues & high idle with the stock cam? What size injectors? I've thought about the GT computer to use with the 36 lb injectos I have, since the Cobra computer changes for the injectors.
This will be a mainly street car, so not too big of a cam, with a 6 times a year to the track maybe. I'd like to go more, but things break there and cost money to fix. I'm not looking to go much more hp than this combo makes due to the stock block.

03-02-2007, 01:03 PM
I think my 42lb injectors really make my idle surge. I did replace my cobra computer (it died) with a 94-95 gt because it was easier to tune. My fuel set-up is in tank 255, in-line vortech pump, 42lb injectors. I'm pretty much at the limit of the stock block (even with the girdle) not to mention the stock axles and t-5 (58,000miles). But the tranny is fine, for now (I don't power shift). I believe the stock cam and lifters work well on my setup. But, I'm not looking for any more power, either.

03-04-2007, 06:10 AM
check out a tweecer over the pms systems might be better for you

03-10-2007, 06:54 PM
Have you thought about going with a Ed Curtis custom cam? It's a little more money, but well worth it IMO. :thumbsup:

03-10-2007, 07:18 PM
You should def get a custom cam, if not you will regret it. I know I do. It may take a little longer gathering funds, but do it right the first time.