Cam rec for roots sbf...

Go down

Cam rec for roots sbf...

Post  torino501 on January 17th 2017, 10:34 am

ok im bored with my lil 327 sbf. this what I have so far. Dart block 4'' bore 3.250 stroke,9-1 pistons, afr 205's untouched with 2.08/1.65 from 2007.. cam is a comp cam
EX282HR 232/240 @.050 565/574 L/S 112 has the holley/weiand 174 with stock pulley. this combo made 425 to the wheel on a mustang dyno with 5.5 lbs of boost. with pump 93 octane. all through a holley 950 H/P blower carb, 1-3/4 long tubes.
im looking at kinda maximizing the combo... going to go big bore pistons keep the crank and rods 4.125/3.250 so 347... keep at 9 or 9.5-1. just freshin up the heads with new springs. put the smallest pulley on there. I should be able to get about 10-12 lbs out of the lil blower. ill be running mix of 93 and race fuel to get the bugs worked out and broken in then switch to E85. id like to maybe go to a blower spec cam with a 114 L/S bigger too. this is in 92 LX 3200 lb street strip. not a daily driver. so a bigger more lumby cam doesn't bother me. its a 5 spd car also... what do yall think... ive got a couple of comp grinds picked out but lookin on what yall would pick for cam specs. thanks homies!!

torino501

Posts : 375
Join date : 2013-05-08
Location : THE GREAT STATE OF TEXAS!!!

View user profile

Back to top Go down

Re: Cam rec for roots sbf...

Post  rmcomprandy on January 17th 2017, 11:43 pm

Compression ratio is to high for 10-12 pounds of boost and 93 octane gasoline.
9.3/1 compression ratio at 10 pounds boost is about equal to 15.5/1 NA. You'll need better fuel.

A custom cam made exactly for that combination would be in order. What type cam are you looking to get ...?
The entire set-up like what is in the drive train of the whole car is needed for a decent recommendation.

rmcomprandy

Posts : 5046
Join date : 2008-12-02
Location : Roseville, Michigan

View user profile http://www.rmcompetition.com

Back to top Go down

Re: Cam rec for roots sbf...

Post  torino501 on January 18th 2017, 10:39 am

Yeah I'm aware of the limits of 93 and boost... I would break it in on a race fuel to get all the bugs worked out then put it on E85. It's a 5 spd car with a 3.73 not opposed going to a lower gear either. From what I've read these little blowers make a lot of heat esp when the boost is up with a small pulley that why I'm wanting to run E85. Seems the E85 helps keep the blower cool. Thanks for the input randy. I do have a hand full of factory billet roller cams out of the explorer GT40P engine... might make a descent core?

torino501

Posts : 375
Join date : 2013-05-08
Location : THE GREAT STATE OF TEXAS!!!

View user profile

Back to top Go down

Re: Cam rec for roots sbf...

Post  rmcomprandy on January 18th 2017, 11:02 am

torino501 wrote:Yeah I'm aware of the limits of 93 and boost... I would break it in on a race fuel to get all the bugs worked out then put it on E85. It's a 5 spd car with a 3.73  not opposed going to a lower gear either. From what I've read these little blowers make a lot of heat esp when the boost is up with a small pulley that why I'm wanting to run E85. Seems the E85 helps keep the blower cool. Thanks for the input randy. I do have a hand full of factory billet roller cams out of the explorer GT40P engine... might make a descent core?

Those Explorer cams do make decent cores for anything needing to be ground on 115 separation with a 1 degree retard of 116 intake centerline; like a supercharged or turbocharged engine might need (Just because it is ground that way certainly does not mean you can't advance it using the timing gear). Keep the lobe lift under about .325" and those are good candidates for regrinding, as long as the distributor gear is not worn.

rmcomprandy

Posts : 5046
Join date : 2008-12-02
Location : Roseville, Michigan

View user profile http://www.rmcompetition.com

Back to top Go down

Re: Cam rec for roots sbf...

Post  jasonf on January 18th 2017, 4:42 pm

Wouldn't that engine combo make about the same power without the supercharger? You have decent parts to begin with. I would think that tiny blower would actually be your restriction.
avatar
jasonf
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 2790
Join date : 2009-07-14
Age : 48
Location : Lafayette, LA

View user profile

Back to top Go down

Re: Cam rec for roots sbf...

Post  torino501 on January 19th 2017, 11:02 am

Well to hit 600 plus hp with 347ci or even maxed out at say 363 id need over 13-1 comp ratio and spin it to 7500 and a pretty brutal on parts solid roller. but id be missing out on the down low torque that the blower would give me. plus with the blower id have and higher average hp and torque #.. I think the 9.5-1 and 10-12 lbs of boost on corn is very doable.. plus the cooling effect that the corn fuel will have on the s/c...

torino501

Posts : 375
Join date : 2013-05-08
Location : THE GREAT STATE OF TEXAS!!!

View user profile

Back to top Go down

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum