My 74 GTV 2000 has developed a strange issue while at the shop having other things fiddled with, Iím scouring the forums here for similar symptoms but have yet to turn anything up just yet. I figured I would share my story and see if anyone has any input / suggestions!
Ok, so... i brought my gtv in for some minor adjustments/fixes. New dash, pull out aftermarket AC components, new steering box, and finally a new set of jets ect for the carbs that Gigem recommended i try out, as i have his old car and it has an identical engine as his blue one with the exception of the jetting on the carbs. He said his latest endeavor to retune the carbs led to big improvements over what i currently have....
Anyhow, we go about replacing the jets and tubes and venturis, upon firing it up, the idle is fine, same as it ever was. Seems to rev freely and act as it did before... that is until we pull out of the shop to shake it down. As soon as load is out on the engine it just Boggs down, no power. No matter what the pedal position is. No missing, no detonation, just feels... well.. plugged up... it drives fine on the lift, it revs and idles fine. This only happens under load... so we reset everything in the carbs back to how they were. Tried to drive it again, same issue...
Things we have tried so far:
Swapped coils, swapped plug wires, swapped distributors for an original mechanical style, bypassing the street fire and msd unit... basically did this one by one and also together, in essence bypassing all of my ignition system with a new one, well known working one...
So We hooked up a color tune and gave the above methods another shot...
No matter the distributor/coil/ignition box that was hooked up we noticed a flicker of spark on the color tune on cyl 1&2 (closest to front) and strong bright sparks on 3&4 (closest to firewall.)
We swapped the color tune plugs around and got the same response...
All grounds on the car were checked, voltage was checked to each unit down the line, it all checked out fine.
Removing the cap on the front cyl carb, we found the seal gasket (rubber) was distorting, like brake fluid on paint kind of distorting. I am wondering if i got some bad gas the day before i brought it over and maybe the accel pump is in a similar state on that carb? Havenít pulled them yet to see...
Honestly Iíve heard from two people to check the exhaust for blockage, as thatís what it feels like when you try to drive it... but it only has one muffler in front of the stinger and the flow out of the tail pipe seems to be ok when idling/revving....
Also found a bunch of rust in the filter/carbs. Cleaned all the jets ect, need to do a more thorough job, but just trying to get it back to 1 right now before i tear it all apart for a HG (weeping oil down the back of the block)
Any ideas?? Help? Offers on the car
i kid i kid...
Here are some specs..
74 gtv 2k
Weber 40dcoe151 (Spanish, ugh i know)
Street fire cdi
Electronic distributor ( not a 123, canít rember the brand right now, started with an H?)
1mm upsized intake valves
Before i was seeing an AFR of about 12-13.5 at idle, 13.5-14 under load
Idling around 11-12 now... at about 900-1k rpm
Happy to provide more info if i can, hopefully someone has some input! Thanks!