Technical question about engine. I need help

[Benjamin]

I need some clues regarding my setup. I took her to a dyno tuner, he said she doesn't breathe. She strill doesn't go very well and I am pissed off (to say the least). Another mechanic (who did the initial roadworthy) says that this is bullwaffle, he is looking at her next week.

Here goes:
- G161 0.5mm oversize
- Shaved big-valve TX head, estimated comp 9.2-9.5:1
- Reground cam by Wade (have specs if needed)
- Adjustable timing gear set
- Weber DGV 32/36 with 140primary and 150secondary jets
- Redline 9" filter (did have two elements stacked)
- Genie extractors, Jethot coated
- Electronic ignition dizzy (from Rodeo/Jackaroo/labelled Gemini) looks almost identical to standard dizzy
- Shuttle elec ign coil and module
- I run on premium unleaded only

Ok, the symptoms:
- Won't climb hills easy
- Loses momentum
- Unresponsive, no snappiness
- Lack of torque (relatively speaking)
- Less willing to rev out all done by about 5000rpm
- When the secondary opens not a lot happens

Generally she has less go than when the engine was in my green TX. When the engine was in the TX it did not have the electronic ignition and the cam was as standard.

The thing that pricked my ears was that the dyno guy said she doesn't breathe. I find that very hard to believe as many of you guys put hotter cams into TX heads without working the head with good results right?

My thoughts:
- Could the cam be timed slightly out?
- Could the dizzy be graphed incorrectly?
- I can't arrive at any other conclusion, these are the only two things that have changed.

When running 145 primary jet I use a tonne of fuel for no gain. When running the 140 primary jet the power delivery feels like swiss cheese. Economy is improved however.

Help me please!!! I beg you!!
Thanx

[WAY2LOWatwork]

your thoughts r what i would be looking at, esp. cam timing. in my old engine i had a very agressive cam (doesnt make power till 5000rpm ) when it was first built it went like a shower of u know what. i had to pull the cam out due to drievability issues, but later installed it again and it didnt make the same power. ne way ended up the cam was out by a coupla teeth and the timing chain was stretched. once this was fixed it made a fair bit of difference.
my other thought is: how big is your cam, is it fairly lumpy? if so your stock gemini inlet manifold could be choking the engine above 5000 rpm and your carb is probably tooo small. a nice side draught could b the answer to all your probs. if your engine isnt a real hottie but rather just a mild one look at a single 45mm sidey (dellorto is a cheaper option) and a redline manifold.
but personally id b looking at the cam timing, make sure that is set right b4 u do ne thing first ecause thats what it sounds like.

[IDAREU2]

The car should still go harder but Ive learnt in my years of building engines is you flow the heads then pick your cam to suit that way they are all matching but you could be in the cam to big side of things and its loosing it protential maybe take the head of and open the ports up a little and get them flowing and set the cam up dot to dot dont try and dial it in that is where your problem could lie even my solid cam in my car is set up dot to dot and that runs sweet dial in cams are for absolute hotties where it is cruisial that the valve closes and opens at the right time because eveything runs so close..

hope this helps

[Adam]

Doing it the proper and intelligent way is considered cheating, go to the sin bin for 9 seconds.

[fluid]

I've got a G180 Gemini turbo running straight LPG, Highflow Garrett T3 roller bearing turbo with ceramic turbine wheel @ 8 psi, Crane 'turbo' grind cam, low compression forged pistons, copper head gasket, fully balanced with a Rodeo EFI intake manifold with all injector bosses welded over and pollution gear removed and custom headers to the turbo with a massive Garrett external wastegate to keep boost in spec....

There....I've had a brag! But most importantly I believe i'm running the same distributor to you and I had problems with it. I'm running a Bosch ignitor module but basically the principal should be the same. First thing, make sure you have the orange wire comming out of the distributor connected to the 'signal' pin of the ignitor....If you don't do this and you connect the white wire the ignition timing will run all over the place with an extremly low dwell and a very crappy spark - Trust me....Your peformance will suck (much like it does ATM). After making sure the wiring from the distributor is right make sure you have a 'full' 12 volts or more at the positive power terminal of your ignitor....Any less than 12 volts and your ignition will start to break down - make sure you haven't wired the 12 volt supply into the old ballast resistor wire....Many people make that mistake and only get about 6 volts to the ignitor....Not good!

Also....Recheck your cam timing....It 'could' be out.

[Ben Wight]

Hey Ben,

I would be leaning towards an ignition problem, or possibly cam timing as well, as your jetting seems to be pretty good, unless you have drastically changes your air corrector jets.

Did you do the cam timing, if so, do the lines line up when at TDC on the compression stroke of cylinder 1? If not, then that is your problem.

Another problem might be the ignitor is stuffed, maybe it isn't wired up correctly. How many wires does it have? 3, 5 or what?

Ben Wight

[Slug]

Im going to expand on what Ben said and tell you to have a look at the air correction jets .. particulary if its straight out of an 2 litre escort .. But if the dyno guy is worth anything this should be right but ... who knows