[Blob]

I have a 283 sbc with a summit 1103 cam, 214/224 .442/.465.
The engine will ildle all day long at about 1000-1100 rpm. When I drop the engine into gear it makes a giant clunk and the whole car lerchs. Most of the time the engine will stall, but if I am quick I can give it some gas and it will keep running. When in gear it is running at about 600-700rpm.

The torque converter I have in there is a summit, I can't remeber what the stall is but I am assuming it is the lowest they make.

I would just like some suggestion on what stall speed I should be looking for. This converter is making the car very hard to drive, I want something where if I put it in gear it will not make the gaint clunk and lerch.

What adervertised flash stall should I be looking for too?

any help would be great!!

[k-star]

Could be another problem other then the converter...

Put a vacuum gauge on it and let us know how much vacuum you have at idle..

With that cam you should be around the 900 rpm or so range for idle speed, the fact it's up around 1100 tells me there is a issue with the carb.


What is your initial and total timing settings????


Keith

[Blob]

At an idle it is pulling around 35 kPa and the timing is about 35 degrees.
The induction is a tpi and megasquirt controlling it all.

It still does not have a perfect tune and the idle surges a little, that is why I have it at about 1000, it might idle lower. Although you can tell the cam is a little large, sure sounds pissed off at an idle!!

I just dont like the massive clunk when it shifts into gear, I fear I am going to break something inside the tranny, I mean its like a tire cherping clunk. when it is in gear with the brakes on it wants move real bad, and with hardly any weight to the car, the rear tires start slipping.

[k-star]

Yea you should see if you can get the idle down to 850/900 rpms that might help some.

That cam is a bit big if it's a stock 283. Have you ever done a compression test??? Do you know where the cam timing is at ( did you degree the cam when you installed it)

I have run 350 with cams in the 230@.050 range with stock converters with no issues. But with a smaller CI engine it gets a bit tempermental over things like this...

Is that 35 degrees at idle???? or total timing???

Keith

[Blob]

I dont know what the exact cr is, it is a 60 over 283 with flat tops and four valve relief. the heads are a mid 80's 305 head. the cam was installed straight up, I did not degree it though. I think its about 9.5:1 or there abouts. I set the distributor in at about 9 degrees. total timing is under wot is about 36, but when it is at an idle under no load the timing gauge displays about 35.

I am going to try and get the idle speed down later today, maybe that would help.

[k-star]

So is the timing totally controlled by the megasquirt???????

No mechanical advance in the distributor??

keith

[Blob]

megasquirt controls everything, regardless I went out there and got the engine to idle inbetween 900-1000rpm, if I try to o lower then that it gets unstable and dies. When I put the car in reverse, or drive, the rpms go from between 900-1000 to around 500rpm. the clunk into gear is alot better now but the engine runs for about 5 sec like its dying and then quits. When it is in gear I have to give it gas to keep the engine from dying and the car want to move like mad.

I am almost thinking of putting a manual in it, aside from the fact that I allready bought a nice lokar shifter, and there is no room for a clutch pedal

should I buy a converter with more stall?, summit has one that is advertised at 1800-2200 or something.

[johnsongrass1]

I don't think the stall is the problem. The fact you can't get the A/F mix right is the biggest problem. A stall might help you overall but it's not your biggest factor. That cam is gonna need a lot of fuel to idle okay and the vacuum is gonna be low. If the EFI system is using the vacuum to monitor load than it can't compensate correctly.

[k-star]

You have a vacuum leak some place.... that is a classic example...

The other thing with the engine being out of tune does not help at all, but if you have 35 deg of timing at idle then there is no reason for the engine to dog down when you put it in gear.... Low initial timing will do the same thing...


Keith

[Blob]

I am going to get some starting fluid out and cheak for leaks. I am also going to try and adjust the VE table for a better, more stable idle. I'll try to update this weekend.

thanks