Motor won't start?
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
Motor won't start? Ok here what and where I'm at. I have a 2000 Camaro SS with the LS1 and ls1 intake. I did a cam swap, headers, and deleted the A.I.R, EGR system stuff. I got everything put back together. New oil pump, rods, springs, 237/242 .595/.595 @112lsa used cam, double roller TC etc. to do the swap. We finished and started the car ran fine for about 5-7 seconds then I shut it off.(oil pressure didn't rise yet) I let it sit for 5 sec. then went to start it up again and all I got was a backfire.The car only turns over and backfires every now and then. Now remember I took off all the EGR and air stuff and put a plate over the egr hole in the intake(no seal) My question is this: I have a good reason to believe that the plate is causing the backfires but was wondering if anyone had any experience(sp?) like this and what was the cause or any ideas as to what to look for after I seal up the egr hole?
TIA
Brandon
TIA
Brandon
if the plate isnt sealed... you have a massive intake leak possibly that is making your car run very lean and that is why it is backfiring, becareful with that oil pressure... make sure it goes up... you can pull the inj fuses and crank the starter to try to get some oil circulated before start up again... try checkin your plugs see if they fouled out already...
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
The oil pressure should come up rather quickly now that I've been cranking the motor over. I will probably use an expandable freeze plug until I get a ls6 intake. Thanks for the insight and if anyone esle has something to add feel free please.
Brandon
Brandon
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
Ok here's an update: I put a expandable freeze plug in the egr port in the intake mani. reconnected the batt. and still just back fires. so I'm going to pull the valve covers back off and re-check all the rods, springs etc. Any ideas are welcome as I need to get this thing running today. So please if anyone has some ideas for me to try I'm open minded at this point.
Thanks
Brandon
Thanks
Brandon
On The Tree
Joined: Dec 2003
Posts: 179
Likes: 0
From: Bloomington, MN
Thats alot of camshaft for a stock bottom end[no valve reliefs] my experience has shown that cams with low 230's of duration is about all you can fit without cutting pistons. Do a leakdown test to see if you did any damage.
Trending Topics
Cam is smaller than the T-rex and that fits on stock heads. I think John is on the right path. Check to make sure everything is plugged in, injectors, coils, plug wires. Is your throttle blade drilled at all? I dont know if that cam would idle without enlarging the throttle blade hole\programming. I dont think it would cause the car to backfire though.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
I agree with denz sounds like it is out of time,hopefully you didn't tear anything up.If it were me i'd pull the heads and make sure you didn't tear up any pistons,valves or anything else.
I hope you put a new O-ring in when you put the new oil pump in! If you didn't you will have to pull everything off the front and replace it! That happened to me, just the other day.
It might be a good idea to pull your pulley and timing cover off anyway to double check everything, including the timing marks. If they are off one tooth you could bend the valves with that big of a cam
It might be a good idea to pull your pulley and timing cover off anyway to double check everything, including the timing marks. If they are off one tooth you could bend the valves with that big of a cam
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
Ok here's where I'm at now, I did a compression check(2 actually had some 130psi) the rest were at 0 
So I then pulled the rocker arms off and did a leak down and found a bent intake valve for that cylinder. So I'm pulling the heads off to replace the valves. Also gonna pull the front cover off to double check that the dots are lined up. I'm still at a loss as to why my valves bent but maybe that answer will come up when I pull the TC cover off and check the dots again. Any other ideas are still welcome as I'm trying to fiqure this all out so I can fix it.
Brandon
So I then pulled the rocker arms off and did a leak down and found a bent intake valve for that cylinder. So I'm pulling the heads off to replace the valves. Also gonna pull the front cover off to double check that the dots are lined up. I'm still at a loss as to why my valves bent but maybe that answer will come up when I pull the TC cover off and check the dots again. Any other ideas are still welcome as I'm trying to fiqure this all out so I can fix it.Brandon
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
Ok the heads are off the car now I'll have pics up later of the bent valves and the marks on the pistons(Thanks Jay 
) So here are some questions for anyone to answer, wether right or wrong ideas spark better ideas. 1) with this cam having 4* of timing built into the cam is there a way to adjust the settings with a degree wheel/kit so this cam will work with out fly-cutting? 2) If not then how hard is it to fly-cut or would it be cheaper to just buy a new cam that is smaller? 3) Everyone keeps saying that this cam is to big for the stock heads but none elaborate on why. My questions is the T-Rex cam is much bigger 242/248 .608/.612 on 110 compared to a 237/242 .595/.595 112 how is my cam to big but the T-Rex not? Or why fly-cut with mine when it's not req. for the T-Rex. I'm just looking for help guys so please any answers are better than none.
Thanks in advance sorry if this post sounds mean or negative but I'm looking for answers to get my car back on the road as it is my only means of transportation.
Brandon
) So here are some questions for anyone to answer, wether right or wrong ideas spark better ideas. 1) with this cam having 4* of timing built into the cam is there a way to adjust the settings with a degree wheel/kit so this cam will work with out fly-cutting? 2) If not then how hard is it to fly-cut or would it be cheaper to just buy a new cam that is smaller? 3) Everyone keeps saying that this cam is to big for the stock heads but none elaborate on why. My questions is the T-Rex cam is much bigger 242/248 .608/.612 on 110 compared to a 237/242 .595/.595 112 how is my cam to big but the T-Rex not? Or why fly-cut with mine when it's not req. for the T-Rex. I'm just looking for help guys so please any answers are better than none.Thanks in advance sorry if this post sounds mean or negative but I'm looking for answers to get my car back on the road as it is my only means of transportation.
Brandon
TECH Resident
Joined: Nov 2002
Posts: 857
Likes: 0
From: Orlando
If you inadvertantly got the cam timing off even by one tooth, this can happen. Sometimes, the dots look correct but end up not being so (ask me how I know). I just did a head swap last weekend and found that all of my pistons have shallow eyebrows on them as a result of the timing being off one tooth before we got the dots realigned. Sometimes, this happens. Once you fire it, if the timing's off all of the valves that are gonna bend will...in about 5 seconds or less. Once that happens, a clean seal and combustion is out of the question.
Thread Starter
Launching!
Joined: Jul 2003
Posts: 237
Likes: 0
From: Ft. Worth, TX
Good points on that one but I figured that out just like you did took about 5 seconds on sunday 
Ok so now my heads are off the car and I need at least new valves to be put in. Knowing the cam I have 237/242 .595/.595 112 what set of stg 2 heads would work with this cam and what mods would have to be done to the pistons(flycutting?) and is that the only thing? and where can I find a set of stg 2's without the springs,retainers and seats(already have some)? I'm thinking either the Absolute s2 5.3 or the s2 ls6's
Ok so now my heads are off the car and I need at least new valves to be put in. Knowing the cam I have 237/242 .595/.595 112 what set of stg 2 heads would work with this cam and what mods would have to be done to the pistons(flycutting?) and is that the only thing? and where can I find a set of stg 2's without the springs,retainers and seats(already have some)? I'm thinking either the Absolute s2 5.3 or the s2 ls6's Last edited by silverbullet00; May 3, 2004 at 09:58 PM.
