390 vs 411 gears
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Do you have any circle track racing in your area. This was a very common tech inspection tool to catch the cheaters. It could tell you with accuracy of under a1/2 ci of what your motor displacement is
https://www.summitracing.com/parts/p...hoCHEYQAvD_BwE
https://www.summitracing.com/parts/p...hoCHEYQAvD_BwE
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
I've seen a lot of people on the forum who have sworn up and down they had 3.55 gears and were unhappy with their launch, only to find out they had 3.08 or 3.36 gears in the rear end.
Have you tested your rear gear ratio to insure you have 3.55's or did the prior owner tell you they were?
If you did not install a 3.55 ring and pinion gear yourself or test it to see, then you may be chasing a problem that does not exist.
The easiest way to test it is to block the front tires, put the trans in neutral and raise both rear tires off the ground, using jack stands; crawl under and draw a line on the bottom side of the tire and a short line along the bottom of the driveshaft; rotate the tire one full turn in the forward direction and count the number of rotations of the driveshaft.
3 turns = 3.08
3 1/3 turns = 3.36
3 1/2 turns = 3.55
Good luck
Have you tested your rear gear ratio to insure you have 3.55's or did the prior owner tell you they were?
If you did not install a 3.55 ring and pinion gear yourself or test it to see, then you may be chasing a problem that does not exist.
The easiest way to test it is to block the front tires, put the trans in neutral and raise both rear tires off the ground, using jack stands; crawl under and draw a line on the bottom side of the tire and a short line along the bottom of the driveshaft; rotate the tire one full turn in the forward direction and count the number of rotations of the driveshaft.
3 turns = 3.08
3 1/3 turns = 3.36
3 1/2 turns = 3.55
Good luck
My 79 came with 3.55, but Bubba wanted better gas mileage and put a 3.08 in.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
send lars your carb and distributor bet thats your problem.
See what details youcan get from the builder first....you can put a borecope down a cyl and see what pn you can find on the piston top and find the pn for the heads that may help
See what details youcan get from the builder first....you can put a borecope down a cyl and see what pn you can find on the piston top and find the pn for the heads that may help
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
And last but not least scenarios: The crankshaft sprocket that comes with three choices of cam timing events, could have been installed using the 4* retarded slot.
Will it run? Yes. Will it run good? Yes, above 5,000 rpms. Will it run good off idle? No, dog. Complete dog. As in, can't get out of its own way, dog.
The valve timing event symbols on those crank sprockets can fool veteran builders sometimes.
Will it run? Yes. Will it run good? Yes, above 5,000 rpms. Will it run good off idle? No, dog. Complete dog. As in, can't get out of its own way, dog.
The valve timing event symbols on those crank sprockets can fool veteran builders sometimes.
Thread Starter
Instructor
Joined: Dec 2014
Posts: 101
Likes: 0
'tKickdown is ok. I really think he got engines mixed up. He was on ebay advertising a 350 with 325 HP. After talking with him I moved up supposedly this 383.
Supposed to be turn key crate engine. I asked for chevy orange. Engine arrived as long block and was red. Said he ships carb and wires etc. separate. Carb came. Spark plug wires didnt even fit distributer...had to buy new ones.
Supposed to be turn key crate engine. I asked for chevy orange. Engine arrived as long block and was red. Said he ships carb and wires etc. separate. Carb came. Spark plug wires didnt even fit distributer...had to buy new ones.
Race Director
Joined: Mar 2016
Posts: 14,406
Likes: 8,212
From: Napa Valley California
Sorry to hear about your situation.
Make sure you go on eBay and post a claim against the seller and find out if eBay has any help for you.
The fact it was supposed to be a turn key create motor and it wasn’t should give cause for something.
Many of have been screwed buy a con over the years and have learned lessons about life and our fellow man along the way.
Good luck.
Make sure you go on eBay and post a claim against the seller and find out if eBay has any help for you.
The fact it was supposed to be a turn key create motor and it wasn’t should give cause for something.
Many of have been screwed buy a con over the years and have learned lessons about life and our fellow man along the way.
Good luck.
Last edited by OldCarBum; Mar 4, 2019 at 10:49 AM.
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Drifting
Joined: Jun 2012
Posts: 1,990
Likes: 183
From: Port St. Lucie Fl
I failed to mention that it has a 2000 stall converter. I think the issue is I got screwed with this engine and with my past cars and just guessing I',m guessing this engine is around 290 horse.
I also installed ceramic headers and marsh pulleys so I think I should have wound up at 400 horse. My dodge ram 390 horse can bake the tires and would probably kick the vettes butt.
Was just trying the easiest route to plant you in the seat a bit better.
I also installed ceramic headers and marsh pulleys so I think I should have wound up at 400 horse. My dodge ram 390 horse can bake the tires and would probably kick the vettes butt.
Was just trying the easiest route to plant you in the seat a bit better.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
'tKickdown is ok. I really think he got engines mixed up. He was on ebay advertising a 350 with 325 HP. After talking with him I moved up supposedly this 383.
Supposed to be turn key crate engine. I asked for chevy orange. Engine arrived as long block and was red. Said he ships carb and wires etc. separate. Carb came. Spark plug wires didnt even fit distributer...had to buy new ones.
Supposed to be turn key crate engine. I asked for chevy orange. Engine arrived as long block and was red. Said he ships carb and wires etc. separate. Carb came. Spark plug wires didnt even fit distributer...had to buy new ones.