Engine is 401 CI stroker, AFR 195 heads. 8:1 static CR. Cam 218, 224 at .050 on 113 LSA. Superram intake. Procharger P600b with intercooler. On dyno it was getting heat soaked to 190IAT. Tried to cool it down between pulls to 140F at least. I got the AFR safe (after previously getting VE tables and part throttle driving nice.) I'm using EBL P4 with the original tables from it which are very conservative. Under boost timing was down to 16 degrees. Power is down! In checking with folk with similar engine combos they are at 25 to 26 degrees timing under boost and are up to 480 to 520 HP from my best of 410HP. My plan is to book another dyno session and add first 2 degrees , then 4, then 6, then 8 under boost and see what the HP does and keep an eye on knock. As long as power is significantly going up I'll increase timing-I'm expecting (hoping) that power goes up with timing increase in boost. Then I'll have to wonder-should the whole table increase? Start with a more aggressive corvette timing table? As in if timing is 35 instead of 24 at 100KPA, then boost retard takes out 10 degrees it ends up at 25 under boost vs. 25 at 100 KPA with no boost retard. I hope I'm making sense with the question/thoughts.

 

What fuel?

whats the air fuel ratio? How much boost is it making?

also look for any pe spark adder tables

 

pump gas 91 octane with 10% (CA) As in the dyno sheet 11.5 and a little lower. max boost 14lbs.

 

when I had a Procharger years ago it would suck hot air right off the drivers side header.

especially when not moving intake Temps were very high. anything you can go up get cool air to it should help if it's anything like mine was. I eventually wrapped the header and that did help some.

 

It is a poor place for the intake-I have a heatshield btween the filter and header. I've been thinking of a way to get outside air to it-probably will put a small hood scoop over it.

 

there's some posts in the big ebl thread about air intake temp sensor location to help with heat soak. I forget the exact details but closes to the air filter opening a believe. in your case maybe not so much.

I'm of no help, sorry. mine was 15lb d1 Procharger that I never got to work right, melted pistons and broke a crank. gave up on it and sold it. things are much better now thou and I didn't have ebl. so hope you get it working.

 

I gotta check my old boosted setup with those heads. They are efficient heads and were sensitive to timing. Thats a relatively small blower im surprised it makes 14 psi on that cubic inch. Intercooled?

typically 32-34 deg on those heads for na motors, and nearly 1 deg per psi is somewhat conservative. But 91 oct you kinda need to be safer. Id say closer to 20 deg timing would be a starting point. You arent too far off. Bump 2 and dyno, check a few plugs. Based on power gain and plug go up more. Problem is it probably will keep gaining til it detonates lol but plug strap should give you an idea

 

Yup it's intercooled with a good sized intercooler-and still put out 14 lbs and still below max impellor speed by 5000rpm. I find it surprising too. I'll increase the 100map timing then to 30s and take out with the boost retard table-carefully!

 

As long as there isnt any other pe mode spark advance. Usually there is in factory tunes. 23-24 deg isnt right, there should be 6-9’degs added

 

F/U-got to 464HP with 8 degrees added-so at 24 degree under boost. This was on a hot day-105F so even with a cool off between runs IATs climbed. Next up is an impeller upgrade.

 

On 14 psi? Seems lower than i thought it would make. But it is a small cam and small blower. Had a D1 make 530’s on 8 with those heads and a tpi setup but tko 5 or 6 spd manual trans tho

 

I was hoping for more-howver before I add any more timing I'm going to pull plugs to make sure no signs of detonation even though there was no knock retard logged. Also the next up cam-230/236 would be nice, however if you pull in for a smog check and they hear any lope it's a fail. I'm hoping the upgraded impeller will give me a good bump in HP.