Blowtorch79

Car only dyno'd a 302 rwhp and 318 rwtq. Stock 165ecm with a level 5 TPIS chip. Custom tune from Precision Autosports in Xenia Ohio. Specs below

L98 block
Fully Forged
10.5 CR
Miniram
TPIS ZZ409 cam
Dart Pro 1 aluminum 200cc (64cc chambers)
comp 1.6 rockers
hardend pushrods
30# injectors
TCI 2400 stall
700R4
moser 9"

I expected roughly 100hp more at the wheels. What could be going on.

Orr89RocZ

iTrader: (20)

Do you have graph and air fuel data? Any idea on timing curve and fuel curve?
Lets start with that.

Next what kind of dyno? I know some local dynos a car may lay down 370, yet another type dyno 30 min down road it put down 450. Mustang dyno vs dynojet.

Some other thoughts. Valve control good? What rpm did it pull to and was graph stable? No floating? Was cam installed correctly and degree'd? Was converter locked or open during the pull?
Sure there are no vacuum leaks? Whats the cranking compression or leak down data? Rings sealing up? Valves are not bent or nothing like that?

I would also expect 350-375 whp with that setup. Also goin to lose abit more power thru 9" rear vs stocker

Blowtorch79

Base timing was all screwed up....I just got off the phone with the guys and he said it was set at -2. Bumped it up to 8 but now its running lean. It's going back on the dyno in the morning. More to follow.

Orr89RocZ

iTrader: (20)

Sounds like they need to get the tune in order. Start with setting base timing to any value 6-12 deg, whatever the motor can idle at with est disconnected. Are they burning chips or just messing with distributor advance and fuel pressure??

Setup the bin file in the chip to match same base timing. Then smooth out your timing table. Try 34 deg at wot full 208 lv8. Also same values for 180-192 lv8 columns. Bring 34 deg in by 3600 or so rpm. See what it does. Make sure you or the dyno tuners decide if they want to zero out the PE mode timing adder table or just keep it in there. Main timing table is easiest to work with while zeroing out pe mode advance. Whatever number you command in main table should be seen at crank.

Then slowly watch air fuel as you work into the throttle. Wideband monitor on dyno. Dont mess with maf tables unless you have to fine tune part throttle and idle.

Use pe mode enrichment vs rpm table to tune wot fuel.

If this shop is any good at tuning they will know how to work these areas using tunerpro rt or tuner cat.

1gary

Orr-he hasn't said anything about the cam spec's yet......................

Orr89RocZ

iTrader: (20)

Its tpis zz409, you can look it up but its a old popular cam. Something like 226/226 at .050, .520's lift. 112 Not the best miniram cam, as i would like to see it on a tighter 109-110 lsa but it has produced good numbers before. Single pattern works well on good heads and exhaust systems. Vette guys have used it alot more. Tpis claim 450 hp on 350's and 470 on 383's but that is highly dependent on heads and compression obviously