[dale302]

Anybody know what is a safe compression ratio to run with a 302W with ported stock iron heads, Kieth Black Hypereutectic pistons, stock rods w/ ARP bolts, and stock bottom end.

I thinking of maybe the Edelbrock nitrous kit with about 100Hp shot.

Any insight or info would be great.

Thanks,

Dale302

 

[89 coupe]

Back in '92 or '93 before I switched to Dart Sr heads I had fully ported '69 351W head with 1.94/1.65 valves and large solid flat tappet cam with over 12:1 compression and I was able to use a 250 horse cheater right off the line and kick in another power shot 150 horse shot once in second gear and lived that whole year with stock rods and KB hypereutectic pistons. Ran 10.20s and didn't have any trouble that whole year. It's when I went to ported Dart Sr heads and solid roller is when the stock rods would buckle from the high compressive loads of just 250 horse shot from cheater. That's when I went to Eagle H-beam rods and quit bending rods but I never had a KB hypereutectic piston fail. I wound up running 9.50s with 175 horse nitrous for years while also driving on the street daily with same KB pistons year after year. 302 rods won't bend as easily as 351W rods because the beams are shorter length and the KB pistons can handle however much nitrous you want to use. The 302 block will be the weak link.

 

[dale302]

Wow 89 Coupe,

That's a lot more than I plan throwing at my engine.

Were you using a main girdle?

My block is a '69 302W with E7TE late model stock heads that are port and fitted with 1.94/1.6 Chevy valves and milled 30mils to bump up the compression ratio. I am running a Performer RPM intake, a 4160 600cfm Holly, and a cam is an Edelbrock RPM Cam with the follow specs.

Duration at .006 Lift: Intake 290° Exhaust 300° Centerlines
Duration at .050 Lift: Intake 224° Exhaust 234° Lobe Separation: 112°
Lift at cam: Intake .310 Exhaust .325 Intake Centerline: 107°
Lift at valve: Intake .496 Exhaust .520


Any suggestions on setting this engine up for Nitrous with adversing affecting it street manners? Do know of any books are info on Nitrous worth reading?

Thanks again,

Dale302

 

[futurattraction]

Here's a link that was referred to on this site a few weeks ago. It's got lots of good info in it re nitrous setup/tuning. Good luck!

http://www.supermegajayman.com/car_stuff/nitrous_tuning.htm

Scott

 

[dale302]

Thanks Futurattraction! Looks let some good info.

Dale302

 

[89 coupe]

I didn't use a guirdle and I wasn't aware of any back then. I knew about the Jack Roush main cap straps but never wanted to try them. I haven't had troubles with 351W blocks of '72 and older which is primarily what I ran and had many 351Ws. I never have used a main guidle until this last 392 I built which I just traded block, guirdle, crank, and rods for a set of aluminum 460 CJ heads, BBF roller rocker, 3/8" pushrods, and high torque mini starter but I will use a guirdle on my big block.