Ford Muscle Cars Tech Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
728 Posts
Discussion Starter #1
I was just looking for a horsepower number and maybe an et guess with my new combo. It is a 306 with kb .200 dome pistons with DOOE-C casting heads that are ported. I think the compression ratio is around 10.3:1. It has a extreme energy cam in it. Xe-268h-10 is the grind number I think. I have 1 1/2 inch primary headers on it with 2" exhaust. I want to put bigger exhaust on it next year, is 2 1/4 big enough for the motor. It has a stealth intake and a 600 vc carb also. Is that good enough, or would a 650 double pumper be better. Any rwhp number guesses would be great. It has a 4-speed and is in a 70 stang. It will have 3.50 gears next spring. Right now it is 2.79. Maybe these gears are why this motor disappoints me a little right now. I was guessing around 275 at the rear wheels, what do you all think? Any other advice on making this combo better is greatly appreciated. It also has roller rockers and stainless steel valves, and screw in studs and all that crap to. Thanks.

_________________
1970 coupe restored with the help of my dad. 306 with 600 holley, Weiand Stealth intake, headers, Comp cam, harland sharp roller rockers, kb pistons, 11:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, an

<font size=-1>[ This Message was edited by: BLstangin on 11/3/03 11:53am ]</font>
 

·
Registered
Joined
·
3,692 Posts
The cam isn't made for all out power so don't expect too much, though it is a very good street cam.

The exhaust is on the small side, though if your going to do it do it once and go with 2.5" all the way out. IMHO I wouldn't use any header smaller than 1 5/8" but that's me.
I'd guess 275-300fwhp.

<font size=-1>[ This Message was edited by: 1 Bad 88 GT on 11/3/03 12:29pm ]</font>
 

·
Registered
Joined
·
728 Posts
Discussion Starter #5
So, you guys think that I should go with 2.5" exhaust all the way? The headers are flowtech's that were like $85, so they weren't to bad, but I can't afford new ones right now, I am only 18, going to college, and trying to make a good street car. I was hoping or closer to 350 fwhp with this combo. Do you think that the bigger exhaust would get me closer. What else can I do, to optimize the combo. Does anyone have a better cam recommendation? I don't want to rev it over 6,500 max. I spent to much money on it to blow it up! The exhaust on there now was on there when I got the car. The cam seems to start to pull at around 3,000 rpm and goes to over 6,300, that is the highest I have taken it.
 

·
Registered
Joined
·
407 Posts
Only two thing holding you back from 350 RWHP: Heads and Exhaust. I would choose AFR 165 heads and Flowmaster mandrel bent 2.5 inch With 1 5/8 headers. carbs ands cams are given way too much attention, when you need to consider TOTAL FLOW ...... I hope this helps. Match heads to cam and exhaust your engine is only an air pump..... intake, compression and exhaust.
 

·
Premium Member
Joined
·
1,369 Posts
BLstangin, as you know we have similar engine combos. i found an engine build up article that mirrored my motor. i punched in all the hp and torque figures from 3000 rpm to 6700 rpm into my drag2000 simulation and it mimicked my 60',330'and 660'. that particular engine made 303hp at 6000rpm and 307 ft.lbs at 4500rpm. that should be close to where you are. drag2000 says you should run low 13s at 105-106mph in good weather and dumping the clutch at 3500 rpm.
 

·
Premium Member
Joined
·
2,216 Posts
It took me a 750 vacuum carb, rpm intake, 224 @ .050 with .512 lift cam, 4.11's, fully ported early 302 heads with 1.94/1.60 valves and a 3000 stall to go low 13's. My car weighs around 3000 with driver and fuel load.
 

·
Registered
Joined
·
728 Posts
Discussion Starter #9
So you guys don't think that 2.5 exhaust is to big for my motor? What do you think the highest safe redline on my motor is? It has stock rods and crak with arp rod bolts and kb hyper pistons. I was thinking of going to a xe-274 cam and reving a little higher, but I want it to last for years as I can't afford to do it all over. It is all just talk right now though. It is for sure getting 3.50 gears and a limited slip next spring, then hopefully exhaust, execpt for the headers, because they are brand new.
 

·
Registered
Joined
·
3,692 Posts
6000 all day long, 6500 max. It will most likely stand more but you want a semblance of reliability so you must compromise. Rpm is harder/more dependent upon good rod bolts and good balance.

<font size=-1>[ This Message was edited by: 1 Bad 88 GT on 11/10/03 10:11am ]</font>
 

·
Registered
Joined
·
728 Posts
Discussion Starter #11
The rotating assembly is balanced and it has arp rod bolts.
 
1 - 11 of 11 Posts
Top