surpip Posted January 8, 2012 Share Posted January 8, 2012 I am looking to trade out my 383 for a 421 SB2 set up, bought the motor for 11k here is what the add said. Professionally built 421c.i SB2 Engine Dart Aluminium block, 4.155x3.875, 14:1CR, 50mm cam ,Chevy Aluminium SB2 heads(211), titanium del west valves Jesel shaft rocker system all Crower rotating assembly, best parts engine is set up for dry sump oiling system and comes with custom aluminium dry sump oil tank and lines and filter, aluminium valve covers with oiling system , never blown and not abused and very little run time since new drop in and your ready dyno reading 869hp and 715fpt @8800 , very smooth and Very Powerful engine with over 20K invested , NO JUNK great engine my loss your gain kinda thing I'm thinking the numbers are overrated but shure am interrested in getting 700HP@7500k im thinking with the short stroke should be happy in the upper RPM range. Waiting for picks of the bottom end to varify components. Obviously i cant run 14:1 on the street all the time so i will need new pistons to lower it down around 11/11.5:1 but what kind of cam profile do they like? I have some Try-y's for it (hope they will fit) so im thinking a 4/7 swap will be in order but does anyone have expirence with these motors? Any tips to make them more streetable? Quote Link to comment Share on other sites More sharing options...
rsicard Posted January 9, 2012 Share Posted January 9, 2012 Surpip: 14 to 1 compression ratio is a bit much for the street. Best way to reduce static compression is to remove one of the heads, the oil pan and one of the piston/rod assemblies. Measure the bore diameter, piston diameter, piston compression height, rod length, deck height and combustion chamber volume. Go to kb-silvolite and run the static compression ratio with different size dished pistons to see what is needed. Then go to jepistons for the SRP professional pistons to see if there is a dish piston that will come close to what is needed. 3.875 is not particularly a short stroke. Retain all else with exception of the pistons and set up appropriate squish with the pistons and head gasket. If the cylinder heads have bolts, go to studs as they are much better for exact torque value. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 9, 2012 Author Share Posted January 9, 2012 Yeah I figured I’m not going to chance this one my 383 I put together myself but I think a monkey can throw together a SBC all let a engine shop do this one for me plus I don’t have a bore gauge or any engine tools like I said earlier I’m thinking mid to low 11's for CR as for the 3.875 I think that would be short enough to push me in the realm of being able to rev in the 7k range? So do you think the cam will be fine as is? I don’t have any specks on it but I imagine revving lower an lowering the CR would have effects on the ideal cam profile. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 9, 2012 Author Share Posted January 9, 2012 (edited) Thought yall might like some pics of the beast. Edited January 9, 2012 by surpip Quote Link to comment Share on other sites More sharing options...
surpip Posted January 11, 2012 Author Share Posted January 11, 2012 Has anyone from here put in a SB2? Or know how well there street manners are? Quote Link to comment Share on other sites More sharing options...
surpip Posted January 13, 2012 Author Share Posted January 13, 2012 (edited) No love for the SB2 hu? I got refered to a guy that might have really good insight on SBC and SB2 cams Mike Jones Jones Cam Designs Denver, NC jonescams@bellsouth.net http://www.jonescams.com (704)489-2449 anyone heard of him? Edited January 13, 2012 by surpip Quote Link to comment Share on other sites More sharing options...
Sumo Posted January 13, 2012 Share Posted January 13, 2012 Forgive my ignorance but isnt that a NASCAR engine? I wish I could build my 383 Quote Link to comment Share on other sites More sharing options...
surpip Posted January 13, 2012 Author Share Posted January 13, 2012 (edited) Yes NASCAR baised but used in circle track and lots of other motorsports as well, should be BA in a 3000# car eh? and shoot me a PM about the 383 thats in it now going to sell it if your interested. Picks on my build thread. Edited January 13, 2012 by surpip Quote Link to comment Share on other sites More sharing options...
surpip Posted January 15, 2012 Author Share Posted January 15, 2012 Recived a reply from mike on the cam I'd suggest my part# R79421A-80412-108 265/271@ .050" .421"/412" Lobe Lift 108 LSA You'll need about a 4,500rpm stall. This will make peak HP @ 7,000rpm, and you can shift as high as 7,400rpm. BTW i have 1.7 rockers thus sounds reasonable to me, what do yall think? Quote Link to comment Share on other sites More sharing options...
jt1 Posted January 16, 2012 Share Posted January 16, 2012 Is it built on a SB2 block or a SBC block? jt Quote Link to comment Share on other sites More sharing options...
surpip Posted January 17, 2012 Author Share Posted January 17, 2012 Its a SBC block used in dirt oval racing Quote Link to comment Share on other sites More sharing options...
jt1 Posted January 17, 2012 Share Posted January 17, 2012 The cam, lifters, and some of the valvetrain is different depending on which block is used. Pistons are SB2 specific. You probably should stick the headers on it and see if it fits between the strut towers. SB2's are much wider than sbc's. jt Quote Link to comment Share on other sites More sharing options...
surpip Posted January 18, 2012 Author Share Posted January 18, 2012 How much wider is "much wider"? didnt look too much wider than a standerd SBC Quote Link to comment Share on other sites More sharing options...
jt1 Posted January 19, 2012 Share Posted January 19, 2012 23 degree heads vs. SB2 head Quote Link to comment Share on other sites More sharing options...
surpip Posted January 21, 2012 Author Share Posted January 21, 2012 Nothing a BFH cant fix ,looks like the exhaust porst are pritty much the same width. I'm pritty shure if the 4 valve Ford motor can fit in there this shouldent be a problem but i still have 3 mounths until i can work on it. I bought Try-y headders for it how much fun do you think those are going to be to try an fit? Quote Link to comment Share on other sites More sharing options...
jt1 Posted January 21, 2012 Share Posted January 21, 2012 (edited) It may work just fine.... I hope it does, I'd love to see a SB2 Zcar. I've pondered it a bit, since the used nascar stuff is readily available around here. I concluded the extra expense and effort wasn't worth the extra hp, at least for what I was doing. The eye candy factor alone would be huge... if anybody's built a SB2 Z, I've never seen it anywhere. I think the driver side header will be a particular challenge, with the motor mount, steering shaft, TC rod and footwell all coming into play. The SB2 ports are maybe an inch wider than 23deg, but at least a couple of inches higher. Also the DS valve cover will be pretty close to the MC. All that can probably be dealt with. There's a local guy here who buys used nascar SB2 stuff and builds dirt late model engines on sbc blocks. They start off at 840 hp, and go over 900 if the buyers budget supports it. Lots of potential there. jt Edited January 21, 2012 by jt1 Quote Link to comment Share on other sites More sharing options...
surpip Posted January 21, 2012 Author Share Posted January 21, 2012 Well id be awsome to be the first one to figure out something SBC related that hasent been done before, all be shure to document it well. 840hp would be great but im only really shooting for 700 all take a hit on hp to make it streetable. Quote Link to comment Share on other sites More sharing options...
RB240zDET Posted January 22, 2012 Share Posted January 22, 2012 How to plan to make all of this power stick to the road? You are looking to make 700hp but how much torque are you looking at producing? Quote Link to comment Share on other sites More sharing options...
surpip Posted January 22, 2012 Author Share Posted January 22, 2012 I have a VLSD R230 in the back running 295's. Thats a start but i never said keeping the rear end in line was gonna be easy haha Quote Link to comment Share on other sites More sharing options...
RB240zDET Posted January 22, 2012 Share Posted January 22, 2012 I have a VLSD R230 in the back running 295's. Thats a start but i never said keeping the rear end in line was gonna be easy haha Haha, very true. Sounds like it is going to be one heck of a beast. Keep up the good work. Quote Link to comment Share on other sites More sharing options...
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