Abdullah

iTrader: (2)

i dynod my friend's 94 A4 LT1 camaro ( which was my previous car in the sig) and i feel upset about that. it only dynod 316rwhp/298 rwtq.

i have the dyno graph but i don't have scanner to scan the graph, i will try to do it soon.

dyno graph :

http://community.webshots.com/myphot...ecurity=AfPxkX

the pic is a little big so be patient. thanks.

here are the mods :

* race ported LT1 heads with stock valves flowing ~268cfm/220cfm.
* custom cam 237/244 i guess the lift is 0.592"/0.592" 112lsa
* Hooker 1-3/4" long tubes and 3" y-pipe.
* Borla cat back with the smallest open plate (no cats).
* ported intake manifold.
* BBK 58mm throttle body.
* compcams 1.6 roller rockers.
* hot cam cam only tunning.
* 6800 rpm limiter.
* moroso cold air intake kit.
* accel 300+ ignition and coil.
* 3.23 gears
* stock converter.

what do you think the problem is? is there some thing wrong from the dyno operator?

i thought i would get like 395 to 400 rwhp untuned?

i think the spark plugs are OK also the spark plug wires.

could it be the dirty air filter?

i don't have more ideas.

thanks for help

SOMSS

iTrader: (1)

You gained about 60 RWHP over a stock LT-1. That's about all your going to get out of that combo. With a good custom tune you should get another 15-20 RWHP. That would be a very respectable 75-80 RWHP gain for a streetable h/c motor.

JustAnIlluzion

iTrader: (60)

nothing is wrong except the !LS1 mod

Abdullah

iTrader: (2)

but i see LT1 camaros with smaller cams are dynoing 350rwhp and more?

pewterta

iTrader: (6)

were do you see that? blower maybe you mean?

roughneck427

iTrader: (12)

That does seem low my mods in my sig and i threw down 350 rwhp and 333rwtq and it was pulling 5-7 degrees of timing out and the injectors were maxed out locking up at 105% duty cycle im taking it back this week to see what difference it made by swaping out injectors and fixing the timing


You need to run a Datalog and see whats happening while its on the dyno and get some wideband #'s and fix the tune from there you have a bigger cam than i do and you are running longtubes

SmokedOutZ28

iTrader: (35)

Post dyno graph... What was the a/f at? My car put down 30hp/48tq more then that cam only!

98SuperSport

iTrader: (1)

my buddys lt1 got 335 whp on a slipping clutch, with bolt - on crap but stock heads/intake 3.42s on a manual and cc306 cam

Adrian87GN

iTrader: (5)

Hmm I don't have any HP numbers but my old basically stock LT1 m6 car ran 8.3 at 83mph in the 1/8th. I think something is off somewhere on your buddy's car. I think it probably would have taken about 300rwhp to push that car to 83 in the 1/8th.

NHRAMAN

iTrader: (1)

.... ..........

Abdullah

iTrader: (2)

i will try to scan dyno sheet today. the A/F ratio was by the dyno wide band black box ( the one that you put a small pipe in the exhaust tip) between 13.2 to 13.3 :1 A/F.

Zepher

the LT1 we built and installed into my friends 82 Trans Am dyno'd 288rwhp with bolt ons, after the LE2 heads/cam package from Lloyd Elliot it dyno'd 380rwhp and the small shorty Edelbrock headers were choking the motor.

Motor was from a 96 and the PCM was a 94-95 since we wanted OBD1.

ls1charged

iTrader: (8)

thats definitely low....get a custom tune for your setup and have him check for knock and what your timing looked like

Abdullah

iTrader: (2)

here is the dyno graph again:

http://community.webshots.com/myphot...ecurity=AfPxkX

the pic is a little big so be patient. thanks.

jimbob

iTrader: (4)

That's about 300 or so SAE corrected...So, yeah your way off...

Ellis's old 350 LT1 did 395 SAE through a 12 bolt and unlocked Yank Thruster pro....GM 847 cam and Lloyds heads as an example...

First thing to check is timing and fuel...you have a ton of break up during the pull, it comes from some where. Lt1's with big cams like afr's in the 12.5 to 12.7 area for max power...It's a reversion problem with our short runners. Small cams don't have this problem....

Second, That's a large cam for how much compression....? Unless you have raised your SCR to around 12 to 1...If your using near stock compression put impalla gaskets to raise comp and lower your quench numbers. Also a cam ground on 108 or 110 LSA with an ICL of 104 or 106 will bring up that DCR...

Third, how much work do you have in the manifold? Stock LT1 becomes restrictive above 240 cfm. Port matching does zero in my book (LT1 manifold). You need to work the injector area to bring up cfm numbers!!!

I would shoot for 370 SAE Unlocked without a cut out..380 open. Stock 10 bolt...

Hope this helps.....

Abdullah

iTrader: (2)

thanks jimbob for the hints.

* the compression is about 10.7 to 10.8 :1 i used felpro gasket i think 0.41" thickness. and the heads are milled but i'm not sure how much maybe from 0.005" to 0.015".

* the LT1 intake manifold is port matched but the injector area is NOT reworked, can you tell me how to rework the injector area?

* my friend told me the rear wheels are hit because of an accident, so the rear wheels are not straight, will that affect dyno numbers? ( but the rear wheels seems fine to my eyes i don't see any thing wrong with them even on the street or on the dyno, there is no vibration because of the rear wheels)

* the A/F ratio is between 13.2 to 13.3 :1 so maybe this a reason.

* i'm not sure of the ICL of the cam, i have to check with my friend even the lift numbers i'm not sure of ( but they are above 0.590" for sure), i'm only sure from the duration numbers 237/244 and the LSA which is 112.


today i dynod my 2000 LS1 M6 camaro and it did 314 rwhp/ 334 rwtq. i'm happy. my only mods are SLP lid and ram air kit and Borla cat back with the closed plate.

btw, although my 2000 LS1 camaro is 314rwhp/334rwtq and my friends 94 LT1 camaro is 317rwhp/298rwtq when we race from a roll he is after a short time a head of me by 5 to 6 car lengths but my friend has some reduction mods done to his car. i didn't do reduction mods to my car at all. i think my friend pulled about 130 to 150 lb out of his LT1 camaro.

i will try to post the dyno graph of my 2000 LS1 camaro soon.

jimbob

iTrader: (4)

Here's some pictures....

If you go as deep in the injector area, you will need to weld like this one...If you leave say a 1/10 of an inch above injector boss you should not break through and need no welding. You can see how much of a restriction these ports are...this is a LT4 manifold but works, the same as a LT1 as far as port work...The lid cut off is for other work being done and not needed for just porting and welding...

Stock deck heights above stock pistons measure between .028 and .036 down the hole...Way to much. With a .029 impalla gasket atleast you would have some quench (anything more than .060, really isn't doing to much). With your .039 felpro your doing very little...This is assuming the block is stock.... Mr gasket also makes a .026 gasket for reference...

I would recommend a different cam. For off the shelf cams I would look for a gm 847...112lsa...but the lobe is advanced to a 107ICL which would more than likely boost your low DCR....On 92 octane look for dcr's in the 8.5-8.8 area... 8.3-8.5 is very safe on most premium gas... I bet your closer to the low 10's SCR than you might believe....If your really want a good cam profile go with a Bret Bauer custom cam, he's on here some where...

LT1's can make some great power but it's the whole combo, not just pick and choose parts that makes the big power.

Hope this helps.....

moeZ28

iTrader: (7)

What kind of valve springs do you have? looks like you are floating the valves. that or your injectors are maxxed out.

SmokedOutZ28

iTrader: (35)

It looks like a opti or fuel delivery problem. Those lines are all over the place.

Abdullah

iTrader: (2)

thanks jimbob for the LT1 intake manifold porting tips. for the cam selection do you mean i have to raise my compression to say 11.5:1 to take benifit of the current cam 237/244 0.592/0.592 112lsa? yes the cylinder block is stock and not decked.

moeZ28, the 94 LT1 camaro is using the ZZX springs ( cam from TPIS) i think i don't have floating problem specially these springs are double and big. the injectors are 24lb factory stock.

i guess the opti is OK. these spark plug wires are live wires from performance distributers and they are still fine. the car isn't driven that much.