what to set total timing

[69chevellef2]

I have a 69 chevelle with a 468bbc,f2,8.5 compression,I was wondering what to set the total timing running 10lbs boost on the street and 25lbs boost on the track,its on e82 fuel

[SMRE]

On the 10lbs of boost we would probably start out at about 38 and pull back to 30-32 max at 10lbs.

On the 25psi we would again probably start out around 38 and pull back to 26-28 degrees at max boost.

Is this intercooled?

Kim
www.smreperformance.com

[69chevellef2]

thanks for the info,no its not intercooled,running on e85 fuel,also running dart pro 1 heads,i dont have a timming retard yet,can u recommend one,thanks

[SMRE]

No problem, that's what we are here for.

Without knowing all of your specs, we would recommend being very careful running 25 psi. It sounds like you are going to be on the ragged edge, but some guys are fine with similar combos. The techs here said they would kinda "creep up" on it to be safe.

We recommend MSD Digital 7 ignition boxes.

Kim
www.smreperformance.com

[69chevellef2]

here are the rest of the specs,dart big m block with billet slpayed caps,srp forged 8.4 compression,4.00 4340 eagle crank,3d hbeam rods 6.385,4.310 bore,comp cam solid roller 114 lobe seperation,dart 345 pro 1 aluminum heads 2.30 and 1.88 valves,msd billet distributer,mls fel pro head gaskets,is 25 psi too much?

[SMRE]

Hello,
I went through your list of specs with one of our techs. He said he wouldn't recommend using those SRP pistons over 5 (five) psi. He said they absolutely will not live with a blower. He also said to make sure you use the L19 bolts on those rods. Please let us know if you have more questions, we are happy to help.
Kim
www.smreperformance.com

[69chevellef2]

thats heart breakin,now that ive got to rebuild my motor,what should the piston ring gap be,ive got the je hardened nitrous hns series,im not sure what my machine shop filed them on,also,i got arp head bolts, not studs,do i need studs,.that should cover everything i hope,thanks for your help,nobody around here ever built anything like this,

[SMRE]

Yeah, I certainly don't like having to tell people things like that. But, it is always better to know before you have a catastrophe. Techs say your ring gap should be 26 top and 24 second. They also say you want to run studs and to make sure you run the inner stud under intake runner, to prevent blown gaskets. We can set you up with the right piston and ring package, if you are interested. Timeframe is between 3-4 weeks. The pistons we use have a hard coating. We actually aren't using the same coating on them you might see on our website. I will try to get pics of the new coating up in the next few days. Let us know if you have more questions, we are happy to help anyway we can.