dan_t

Well my block and rotating assembly are off at the machine shop right now to have the clearancing work done for a 383 build. I'm soooo bored of waiting for it to come back I thought I would arm myself with all the tools that I need to get this tuned when I do finaly get it built.

I have tuned my very mild 350, with a converted LT1 intake so I do have SOME background but I'm not sure how well thats going to hold up with this build due to the Camshaft, Heads and extra CI.

The specs are:

1985 Corvette - Auto 700R4 - 3.07 gears
Gen1 2pc Rear Seal, 2 Bolt Main
383 Scat 9000 Crankshaft, 5.7" Rods and KB Claimer Hyper Pistons
AFR 195 heads 75cc - 9.8:1 compression
Comp Cams 306 - 230/244@.50 .544/.577 lift with 1.6RR
Hedman Street Headers / Corvette LT1 Exhaust System (No Cats)
LT1 Converted Intake
30lb GenII Bocsh Injectors with Adjustable FPR

I'm running a 7730 ECM and have been using the SuperAUJP bin with extended tables. I have got my head around the VE tables and spark tables. I was lucky enough not to have had to adjust any of the other "Trim" tables in the past.

I plan to tune in open loop using a LC-1, with NO PE to start with - I think this is the best way to get "true" readings to work with. I'm also considering the NVRAM addon as it looks like this would speed things up somewhat! I have seen that AUJP_V4 has now been released so I think that would be a good starting point.

Now I think I need to adjust the displacement and injector constant up to 30lb. What else am I likely need to do? With the cam that I've gone with I'm expecting a choppy idle so I'll start by bringing the RPM up a bit.

What should I expect to see with regards to Delta_vs_RPM_vs_TPS?

Anything else that I should have a look at with regards getting good drivability? I think I'll be OK with WOT stuff its the around town driving that I'm more concerned about.

Any advice greatly appreciated!

dan_t

I should also ask... I understand that the Cam will probably create a LEAN reading on the lambda, I'll use the new Open loop at idle of AUJP_V4 to combat that when in closed loop.

Is there any good way to tell a false LEAN reading from the cam and a TRUE LEAN reading? I don't want to over compensate myself but I also don't want to run dangerously lean either.

anesthes

iTrader: (12)

I could never get that cam to work in closed loop with SAUJP. Maybe you will have more luck. My combo was almost identical to yours. 10:1, tfs heads, cc306 cam, 700R4, miniram, 30# injectors.

-- Joe

dan_t

350 or 383? I thought yours was 350? I have read some of your posts on this cam before, I beleive you went back to the CC503? I'm sure I read that yours was 350ci?

I was hoping that if it was "on the limit" on a 350 then it would be possible in a 383?

anesthes

iTrader: (12)

My current block is bored .040 over, so it's a 358. 25 cubic inches could mean a lot when it comes to cams, and the cc306 could work a lot better for you. I have some other gripes with the cc306, like its huge split favoring exhaust duration. It's a cam designed for stock or lightly ported GM heads with weak exhausts. I can't really say a trickflow or especially an AFR falls into that category.

But yeah, I went back to the 503. I tried a few cams in the past 4 years and going back to the 503 has been the best. I've never done a stroker before though.

The other issue with the 306 (again, could be cuz my motor is smaller) is under 2200 RPM the car would surge and buck. It made overdrive useless, even with my 3.54 rear end. I changed too many things at once between last year and this year (busy winter). Have a supercharger again, a 6 speed trans, and the 503 cam. Car is a rocket. last year I hated it and wanted to push it into the ocean.

-- Joe

dan_t

I know that Over Camming an engine is pretty common mistake by us younguns, I guess only time will tell once its all together. I think it would be a good cam to make some nice power but I don't want to loose all drivability. Having an Auto also I thought might make it slightly easier to live with due to the torque converter taking some of the edge off of it?

anesthes

iTrader: (12)

I don't know about the last part. I found it harnder with the automatic. It shifted like you wouldn't believe (rebuilt it with the transgo stuff), but the whole converter thing I don't get. Just felt weird to me. I sold my converter to a forum member who seems to like it. (was a raptor 5x, I think 2800 or 2900 or something like that stall rated for like 750hp). Maybe I had the wrong converter.

For me it was a bad combo. I thought I had it 'right' on paper, but it didn't work out. Car was lame. Part of it could be blamed for me not knowing how to setup an automatic properly. If I had petek/floorguy in the shop he probably woulda set it up differently and it would have worked better, but honestly I missed having a manual trans too so it helped motivate this winters work. I think the 306 cam might have been worse with the manual though - i'd probably have to throttle the crap outta it or slip the clutch a lot more leaving a light with the 3.54 rear end. I really think that cam is meant for 3.73-4.11s on a singleplane/lt1 intake. I kinda wish I went with the 3.73s too, as I've yet to figure out what 6th gear is for on my setup.

-- Joe

ULTM8Z

I see you're running an LT1 converted intake. In that case, my initial starting point for ALL of the accelerator enrichment would be a 1994 Trans AM with automatic trans. The broadcast code is BDZL and uses a $DA3 ECM definition file. Do a search becuase I think the tables were posted. The majority of the tables are the same as $8D, so you can just copy and paste the values into your bin.

I'm running those AE tables almost as-is on my Camaro with a cammed ZZ4 and AFR heads as well as a Miniram. This should get you to within 10%-20% of ideal. I've had to do some very minor tweaks to the tables for my combo, but by and large, they're nearly in stock form. Your cam is quite a bit more radical than mine, so you may have to tweak yours a little more.

dan_t

I've already copied a lot of the BDZL tables across and adjusted them. It was a lot closer than the AUJP VE tables.

I'm not 100% sure what to do with regards the Cam now, I'm going to find it hard to sell it in this country and shipping is going to be a nightmare with regards weight and cost. I'd probably lose most of the value of it.

On the other hand though I don't want something thats not going to work for what I want.

I think I need to speak to some other people that have used this cam and maybe in a 383 setup (No disrespect Joe) to see what there views are on it. I've no doubt that what one person would call street-able another would call track only.

dan_t

I have made this thread to get views on people outside of DIY-PROM
https://www.thirdgen.org/forums/tech...ml#post3774184

dan_t

just to update this old thread, i've done a few evenings tuning now and it drives just like it was stock... even with 1.6 ratio roller rockers on there. Idles at 800rpm no problem. I do get a slight surging once in lockup but thats cleared by around 55mph...

Orr89RocZ

iTrader: (20)

what you set your idle settings to? Did you have to play with the o2 constants at all? i'm having abit of trouble with my MAF setup trying to get a similar cam running on my 383 lol