Which Cams work with speed density ?

M.A.V.

Founding Member
Jun 28, 2002
107
0
16
Georgia
My son (16) has a 1987 LX automatic that is completely stock except for a new 2 1/4" dual exhaust without cats. At this time the car is plenty strong enough for him (I say so! lol) But he really would like for it to have a lope when idleing. I `ve heard that it is best to run a 114 l/s cam to keep the speed density from going nuts. I have a WG 1190 Wolverine cam in storage,
but I`ve heard mixed info on how it would act in a speed density car with its 112 l/s. Who here has run a thumpy sounding cam without trouble in a speed density car?
Thanks .
 
The Crower 15511 and several Comp 260?? and 270?? cams will work.As you said 114 lsa, 220 or less @.050 duration but each car is different. To me, if all your going to do is change the cam, it's not worth the hassle and expense. My boy is 16 also and I am looking for him. A friend of mine has an auto for sale and I think the only things I would do for now would be gears, shiftkit, tranny cooler, and converter. FWIW I kept the stock cam for my combo and IMHO it's plenty.
 
The SD system is sensitive to anything that significantly changes the vacuum signal - and many cams do that at idle. The challenge as I see it is that the very thing that he seems to want (lumpy/lopey idle) comes with significantly reduced vacuum at idle. The SD system isn't going to like that. There are cams that work with SD - but you're not likely to get a real lumpy idle out of them - BECAUSE they work with SD. Besides that, unless other changes are made to work in combination with the cam (heads, intake, exhaust) it's likely that just a cam change will take away as much or more on the bottom as it returns on the top. MANY people out there have screwed up a perfectly good running car by sticking too much cam in an otherwise stock engine. Time to do the 'dad' thing - and help him understand that lumpy sounding, but running like crap isn't nearly as cool as mild sounding and running strong.

If he just wants it to sound lumpy - have him pull a vacuum line off. That'll lump it up pretty good! But if he wants it to actually perform better there are other things to look at. I presume you've removed the silencer from the fenderwell of the stock airbox? Put a flat panel K&N filter in it. Bump the ignition timing up to 14 btdc. Lose the stock gears and put a set of 3.73's in it. And for a budget change - have tmoss on the site port your stock lower intake - it's the biggest restriction on the car. Those changes will make a noticeable difference in performance across the rev range without hurting drivability.

If he's insistent on a lumpy cam (not recommended without other changes) I'd get ready to convert to mass air. The SD won't like the really 'lumpy' cams.
 
I agree 100% with MIke...I would also like to point out that yes a cam will give you the sound, HOWEVER as in my case you may end up with a SD system that just flat refuses to adapt...I had surge/stall/hanging issues, and an exhaust at idle that would make a grown man cry (RICH!!!!). Many have good success with moding SD cars, but some don't.
 
crower 15511 and 15510
compcams nx264hr
comp cams xe264hr
comp cams xe270hr
the steeda # 19 is right at the max of the sd limits, I havent saw any one run this one in SD yet.
I ran the nx264hr with 24# injs in my sd combo with thumper heads tmoss lower and then a cobra intake later. It ran fine. I eventually swapped to mass air for future mods. It ran pretty much the same either way. I realy liked the nx264hr cam with the 1.7 rockers.

here is a sound clip of the nx264hr with 1.7 rockers thumpers and cobra intake with off road h pipe 2 chamber flos and mac 1 5/8 uneq shortys. I ran 13.90@ 100 mph on street tires with 1.98 60' 3700# race weight with that set up

http://www.50tech.com/users/sljccj/Mafexh.wav
 
Thanks alot for all of the input ,and especially 5.0Droptop for the sound clips.

The thing is ,at this time my son does`nt have the funds or the driving expertise to do alot of mods on his car. For now he just wants it to Look and sound fast (poser!) so it will remain stock for a while with the only mods being Flowmasters ,Wheels,and as thumpy sounding cam as the speed density will allow. He really likes the sound of the nx264hr :D
If it can be used in an otherwise stock engine thats what we will go with.
 
M.A.V. said:
Thanks alot for all of the input ,and especially 5.0Droptop for the sound clips.

The thing is ,at this time my son does`nt have the funds or the driving expertise to do alot of mods on his car. For now he just wants it to Look and sound fast (poser!) so it will remain stock for a while with the only mods being Flowmasters ,Wheels,and as thumpy sounding cam as the speed density will allow. He really likes the sound of the nx264hr :D
If it can be used in an otherwise stock engine thats what we will go with.

It will work fine for a stock motor.
 
Michael Yount said:
Also not Mav - 5.0Droptops other mods - the cam is gonna sound and perform differently in your mostly stock motor.

Yes I had stock bottom end, But I had Thumpers Ported e7te heads with the cam. They flow more than stock heads,.
 
Thanks for the tips again guys...later on maybe he`ll have something closer to mine in his car ,,,Yea yea I know its Old school...But its fun!
 

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This'll be a good learning experience for you too then. I started off with carbs - but learned about efi as the years went by. Now, I don't think I could go back to a carb. Never too late to learn about them - my daughter's headed towards her 31st birthday. Just think "laptop" instead of "jets". ;)