to lt1s10

today i hooked the vac gauge to it and drove it to work. when you stop at a light the gauge is moving between 6 and 5 inches.i pluged all vac ports and sprayed a half can in little squirts no change . i called comp cams fo help they told me it should have 17 inces at 900 rpms, if i do that , i cant even put it in gear without it stalling the adjustment on the rockers are zero than a half turn, i had them one turn they say thats the problem so i remove the valve covers and back them out a half turn no change. i hate bothering you with my problem but its really pissing me off! the only thing i can think i could have done wrong is edelbrok wants you to use mr gaskets because of thickness i used felpro so this weekend im going to change the intake gaskets and see what happens. i read were you can set youre timing with a vac gauge by turning the dist. to you get the highest vac reading and then retard it 2 degrees when i do that i end up with 38 degrees btdc do you have to set the idle and continue keeping the it set at that rpm while turning the dist. ?thoght maybe ignition or valve timing just a thoght**) :CRY:

Do NOT change the gaskets. I am using Felpro gaskets on my Edelbrock Performer series intake manifold and they are the best. I at first used Mr Gasket ones and they leaked like crazy (part of it was my fault but not all of it). But anyways what is your problem? You said something about stalling when putting it in gear and that's all I know. Reason I ask is that if your question is what I am thinking it is then we both have the same problem here on a different one of my trucks (the one with stock intake manifold and gaskets so no worries on that one heh).

i posted on small block chevy the post is called question its about two pages long fmxhellraiser my problem is i cant get 17 inches of vacuum at 1000 rs i have to idle at 1350 to get 750 in gear every one says vac leak i tried and tried and tried iI CSANT FIND NO F VACUUME LEAK!!!!!!!!!!!!!!!!!!!!!!!!!

Oh ok I remember reading this one. Nevermind your problem is a little more than mine. Here is what I would do. I am not sure if this works on car motors but it's what I did with motorcycles when I would jet the bike right and plugs kept fouling and it was running bad.... I would get carb cleaner and spray it around the cylinder head gasket first. I would hold the throttle a low idle steadily and if it sputtered or died I had a leak. Then if I didn't I would move onto another gasket. Try doing that. See what happens.

i tried carb cleaner today i cant find a leak . see this thing has a gear drive in it and beleive me i would have known if it would have sped up i dont know man its got me so you dont think thickr gaskets are going to help huh?

I went back and looked at the old posts.What have you changed on the engine?Has it always had this low a vacuum reading?When did you first notice this low vacuum reading?

Nope. I doubt gaskets are your problem. I use the same ones that you have (with the little blue round bead seal around the ports right?) and no problem at all. Felpro seem to be one of the best gaskets out there. Do you use your end seal gaskets (the cork ones)? If so then I recommend taking them out and not even using them, but two beads side by side of sylicone and you will be fine. First time I ever put gaskets on a manifold I used them and they leaked slowly, second time I accidentally hit the back one in, didn't know, started the motor up and oil all over the place and had to redo it. By that time 3 guys told me to not use them. I redid it with Felpro, didn't use the end seal gaskets and haven't ever had a problem yet. That doesn't mean that's your problem or nothing but I am just saying. I am still new to hot rodding and learning so I can't give you anymore info really on this subject or else I wont be 100% sure and I don't like doing that. I am very curious as to what is wrong with your motor, I will keep up with this thread for sure though. Take a break from it for a while, calm down and then maybe by a few more days you will have an answer.
Good luck man!

Denny,he states he has a 268 comp cam.I think this cam has about 222 degrees at .050.Which I would say really needs at least a stall speed of 1,800.

it don't sound like the gaskets, S19243H. your valves should be ok, sounds like you have a timing problem to me. if you move the dist. to you get the highest vac. reading and then move it back 2 ins. of vac. then that should be your best timing. if you have anything other than around 10 degrees at 900 -1000 rpm then the mark is wrong on the HB, but that should be your base timing. plug the vac. adv. off while you do this. you will need to adj. your rpm with the timing change. sounds like to me after you set you timing with the vac. gauge you didn't idle the carb. back down, or up which ever one was needed. as far as the conv. goes looks like the cam people would have told if you need a stall conv. but if you get the timing right i think that will work itself out. do the vac, deal and lock the dist. down, plug the vac. adv. back up and adj. the rpm's and carb. air screws as best you can get them and see that you have.

comp cams claim the largest cam you can run with a stock converter denny thats why i bought it ,because the cam i had before in the motor was way to big after installing this cam i got he same idle response ive been driving it this way since the install eric i knew it wasnt right and going to car shows and talking to fellow rodders i decided , im going to find out whats wrong or else

youre right lt1s10 i didnt back the idle down while moving the dist , think i need to kick back and think about this for a day or to thanks bud

Has anyone mentioned anything about cam timing?

no:CRY: :CRY: :CRY: :CRY: :CRY: :CRY: :CRY: :CRY:

you'll need to do that, when you increase the timimg the rpm's will increase also, so you'll have to adj. back on you rpm's. as you increase your timing. you all so need to find your true TDC, but for the time being the vac. gauge should work.

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Originally posted by S19243H
no:CRY: :CRY: :CRY: :CRY: :CRY: :CRY: :CRY: :CRY:

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it wouldnt run as good as it does if the cam was off. you say you have been driving it right?

i put this motor together about six months ago when i degreed the cam i had the heads off and used a piston stop to find true tdc the ballancer lined up thats why this whole thing is so confusing:confused: **)

i drive it every chance i get i took some pics and downloaded to the comp how do i get them here

This might be way off base but when I said cam timing I was thinking what if you have a crank gear that has several keyways and you have it retarded 4 degrees?I do know that crank degrees are different than cam degrees because the crank moves at twice the speed of the cam.Another crazy idea.What would happen if the cam gear was drilled out to except the bushings to either retard or advance the cam and the cam was also retared 4 degrees.Whould the engine even run?And how well would it run?

not me eric this motor has a gear drive no extra keeways in the crank gear only offset bushings in the cam gear and i used the one 0 degrees i wouldnt play with what i dont know you could bend a valve or worse my cam was degreed in

did it ever run good? where did you put the cam gears? did you adv. or retard the cam gears? if you have max. vac. and your timing mark is on 38 degrees then something is wrong, unless you had the rpm set 2000 rpm's or higher. that sounds like the total timing, but that shouldnt be in below 1500 rpm's.

S19243H get your max. vac. less 2 ins., adj. your rpm's and adj. your carb, and see what you have. if youve got 15 to 16 ins. vac. @ 900 rpm's, you dont have a leak. late timing will cause low vac. also. be sure the machanical timing adv. weights in the dist. are free also.

Oh wow great thread going on here guys, sorry to butt in. I just have to say that I am curious about answers to Erik's question about the bushings and is that really possible to do? #2. The answers to the questions about the 262 comp cam package..... because I want to use that set-up in my little engine. If there is anyone that has used that set-up with success, I would surelike to hear about how you set yours up. Well appreciated guys:D

Also when you want to time your engine with a vacum gauge, you go right of the manifold right?

S19243H, what kind of carb do you have?

A buddy of mine had a similar issue where his motor had a "mid-throttle" lag that would disappear once the throttle was opened further. His vacuum was a little lower than normal and could not find any leaks. Called Edelbrock tech support, they mentioned that it sounded like a lean spot caused by too weak of a step up spring. They make a variety of springs that allow the rod to get pulled down into the jet based on manifold vacuum.

He installed a stiffer step-up spring and the transient lean condition disappeared.

Not sure if this is unique to Edelbrock products or if you even have an Edelbrock carb, but it sounds like you have tried a lot of stuff already...

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Originally posted by brickman
Oh wow great thread going on here guys, sorry to butt in. I just have to say that I am curious about answers to Erik's question about the bushings and is that really possible to do? #2. The answers to the questions about the 262 comp cam package..... because I want to use that set-up in my little engine. If there is anyone that has used that set-up with success, I would surelike to hear about how you set yours up. Well appreciated guys:D

Also when you want to time your engine with a vacum gauge, you go right of the manifold right?

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brickman go stright to the manifold for your vac.. on the drgreeing of the cam you can do it at the crank with the gear or dif. key in the crank or use a bushing in the cam gear. dont make no dif. which, but dont do both. 4 degrees adv. will give you a lot of bottom end. ive been both ways, ended up back stright up each time. dont know about the 262. S19243H its a lot of good ideas here, but you need to fix one thing at a time. cant keep jumping all over the place. get you timing set right and if that dont fix it then go to the next thing.

Going with lt1s10 going to get the timing right first late timing causes low vac ive tried 3 carbs on this motor with the same results edelbrok holly and now q jet no change

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Originally posted by S19243H
Going with lt1s10 going to get the timing right first late timing causes low vac ive tried 3 carbs on this motor with the same results edelbrok holly and now q jet no change

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ill help all i can, but you have got to take it one step at a time.