THSCC Forums

Hey Anders - I'm looking for the rest of the story too! OK, here goes. I'd appreciate any input anyone has.

The car - Factory rated at 90 HP, so we'd expect 70 or so if all is well. So we're missing 20-25 HP. Idles, revs, and runs well, good midrange torque. Totally loses breath as the revs rise - the torque curve peaked around 2500 RPM and fell nearly linearly all the way to redline. Very unusual even for a carbed engine. HP curve is almost flat - not what you want.

1. Initial run around 48. A:F looked fine (need to look up what it was)
2. Changed timing to "full opposite" = 42 hp (determined retarded)
3. Put timing back to full advance. Did another run while watching secondary throttle. Throttle wasn't opening. About 50 HP this time (higher b/c missing air filter).
4. Leaned over the engine and shoved a screwdriver into the secondary during the run. Went to like 52? HP Noticeable improvement across the board. A:F went wayyyy rich.
5. Repeated #4 with compressed air shot into the carb secondary. HP bumped up to 54 (?) and A:F was OK.

So the secondary problem appears to be part of the issue, but at this point it looks like it may only be 10 of the missing 30 hp.

It really runs like there is some massive breathing restriction, right? Works fine at low RPM and not at high. What could this be?

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Mike, I posted some suggestions before and never heard if you checked:

I think the cam timing is off. Either the timing belt jumped a tooth or the timing belt was assembled with the cam gear(s) in the incorrect alignment with respect to the crankshaft.

If the cams are advanced in relation to the crank it makes the EXACT symptom you describe.

Jim

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Jim Williams
'94 GSR Integra, TIR 12

Mike,

I have not reviewed this thread in regard to all the things you've checked but as I recall you've checked for exhaust/cat restrictions. That pretty much leaves cam timing or maybe really gross flow restrictions from sludge/carbon buildups on the valves or the ports/manifolds (assuming you've done a leakdown test to check for bad cylinder(s)). At this point it appears that the carb "secondary problem" is a result, not a cause (i.e. no flow out means no need for more flow in). Have you tried disconnecting the exhaust pipe right after the exhaust manifold to be absolutely sure that nothing is happening to block flow through the cat or muffler or pipe? I seem to have heard of high quality exhaust pipes with an inner wall that collapsed even though the outside was fine.

Edited to update: I reviewed the old thread. I see clogged cat is not a possibility Is there anything in the exhaust system including the exhaust manifold that could be plugged? Old "merican" cars used to have manifold heat control valves that could, I think, stick so that the exhaust flow was restricted.

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Dick Rasmussen

FS 50 2018 Mustang GT

Very interesting. Any idea off of the top of your head how to easily check this? I'll go look in the manual...

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

sounds like cams are off a tooth, working for toyota I have delt with this simular problem, if the cams are off that effects the vacuum that helps operate the secondaries of the carburator. pull the front top timing cover off and make sure 100% that the car is in time. it does make a big difference.

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beware of EV powered Ford EXP's they are quiet and come for you when you least expect it... hide behind an aluminum light pole...... ya that will help

Well I heard a message from Adam that a tree has fallen the car where it's stored in Raleigh. Apparently the windshield is smashed, and the roof is dented up. A message perhaps?

Hahahaha, that's just funny for some reason. At least it won't start anymore either.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

So if we remove the windshield that will save weight right?

And if the windshield is gone then we don't have to worry about enclosing the passenger compartment anymore, so.... we can pull the rest of the glass, the motors for the windows, the heater core.

I think the rally beater is about to get lighter and uglier.

ps. as an afterthought if we fix the timing belt issue then it will probably start easier so we can say screw the starter and pull it too. We will have to commit to push starting but that is a small cost for yet another oppurtunity to lose weight.

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OK so I'm back in. Now which tire should I buy??

Well let me clarify. A large branch from a tree over the beater fell on it. Adding a quite large spiderweb to the winshield, though it is at the top and driver's side and not really in the line of sight. Said branch also let its mark on the roof by way of several nice size dents.

Sounds like a good excuse for you guys to go ahead and turn the beater into a a permanent drop-top. No rules against convertibles right? Saves weight, looks cool, and adds natural A/C. As long as it never rains you'll be fine.

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Vincent Keene
'06 Ford Mustang GT (track rat)
'15 Dodge Charger R/T (yeah, it's got a HEMI!)
'07 Ford Fusion SE (205,000 miles and counting)
'98 Chevy Z-24 (retired)
'93 Acura Integra (Team SWB 24HOL Car)

Could you imagine how much colder it would have been at 4 oaks if you would have been driving a convertible.... Brings a whole new meaning to the slogan "Freeze your grass off"!

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2001 Honda S2000 - SOLD
2012 Boss 302
2003 BMW 330i

Since the rules of the rally beater were that the person using it had to fix it when it was broken and buy it off of Mike, is he going to have to buy it off of himself and repair the glass and roof?

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Has no responsibility whatsoever.

Ok so here are the dyno pulss for the rallyx beater in all its glory;



I left out 2 runs that were basically duplicates of others.

Also of note was the fact that the Rallyx beater now holds a dyno record at CAM, the lowest hp pull ever. By a car anyway, they actually dyno'd a go kart, 4.9hp and 5.6ftlbs

well, with all the insulation gone on the roof, could we possibly hammer out the dents and repair the roof of the car........

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hey yall,watch this...