Thread: 383 build-Something Caught My Eye

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Well playing with it again.Pat/Richard if I go to the RHS TQ 64cc head and go .010 down it works out to be cr of 9.47.

I plugged in the correct numbers in the formula below.It won't copy and paste that way.

Engine Compression Ratio (CR) Calculator

That would get us back to where we wanted with the added bonus of the head intake runner we wanted too.

Damm,don't know where I came up with the pistons being 12's.


Richard the heads are not purchased yet.We are spec'ing this build out.So to change out to a 64cc head .010 down is no problem at all.

Man-that's embarrassing.But better to be corrected that be cash out wrong.No wonder Pat was talking the 64cc heads all along.Still a newbie mistake on my part and I admit it on the open forum.

Thank you

we were hear some time back and i was thinking you did not want to run good gas in it or you may not find good gas ? so we went down 1/2 a point or so . may not ping and if it starts your pulling timming out its never going to run good . i can not say under a very hard load its or going to death rattle at 9.5 small dur cam and low grade gas .i would stay on the low side cr . 1/2 point may not hurt or help i can not say if you want the 64 heads i will get you any thing you want

Well I am a strong believer in RHS,but if they are not going to work than they aren't.What's your opinion of a cr of 9.21 with a world 67cc s/r t/q part number 4266K??.I do think you brought those up once before.Gas I would use is 92.

use any head you want . i do not mean this in a smart way .the pistons are fine with the 72 cc . just live with the 8.94 or just cut 2 cc off the heads and that not much .010 thats 2cc (but i cc as i cut the heads could be abit more or less) and use the 180s . the 383 will take either head and like i said on this i can not give you real numbers as all my numbers are base off stock heads with a 202iintake and 1.6 ex if tech has flow numbers on the heads let him run the two heads at 9.1 cr ? and see. with the small lift numbers it could be very close. yep i did talk about them and i did say i like the PBM thunder heads too

OK-sounds like a plan.Richard-could you please run the numbers for both heads??.RHS12001's and World sr tq'ers part number 4266K's.

Thanks

Originally Posted by 1gary

OK-sounds like a plan.Richard-could you please run the numbers for both heads??.RHS12001's and World sr tq'ers part number 4266K's.

Thanks

Just so Richard see this.

Thanks Richard

Ok the next thing will be the rods.They are 5.7 scat 4340 I-bean rods w/arp 9740 7/16 cap screws Part number SCR5A7.Bushed with a wt of 595g.

That will be mated with a Howards 4340 steel "Track Smart" crank.Don't look for one that is a 3.75 stroke and 5.7 rod.They are not made any longer.I got the last one.

Over the wkend I am going to review the cam selection and make decision about that.

for street use press pin N0 worry about beating bushing out

Pistons come with a floaters and locks.Mates up with the rods.

Really I should answer you this way Pat.Btw-I have had a terrible day.One thing after another.Why should I convert to press fit when the rods are floaters??.I don't understand.

did you buy the rods ? scat /pbm rods come press and floaters. why would you need floaters for every day steet use . you have pistons that can go floaters there cut for locks but ..... i used them many times with press fit, less parts less worrys but do what you feel is right

I thought you might have had problems with the Icon pin/locks.The Scats with 7/16 bolts only come as floaters.Lots of other features too on the part number.

nope i just do not see a need for floaters in a every day engine and some race engines .more cost more parts and are not better less you plan on taking your piston on and off your rods alot. i can get a5.7 rods with press pin with scat scr5ap but like i said use what makes you happy 7/16 bolts ? hell i have many bbc with 3/8 bolts that seen the bad side of hell . stop building a race engine for a tow truck

I want to go this route for reasons I can tell you about soon.

Pat-sure is used to tow.It is also used to put a smile on this old time racer without the trailer too now..........