I have an 86 Regal that I stuffed a 5.3 lm7 in. The car was set up to be turbo but my plans for the car have changed. It is a part time driver and I just decided I didnt need all the power the turbo 5.3 would make on the street. Here's the specs.

04 lm7
arp rod bolts
arp head studs
02 ZO6 cam
hand ported heads (casting cleanup with polished exh runners and chambers)
GMPP single plane intake
700 cfm holley dp
pacesetter lt's
2.5" true duals
th400 w/ 3100 stall 2.2 str edge converter
3.08 gears (were for the turbo)
3100lb 86 Regal
MSD 6010 box 30* at full advance

I think the cam will be a problem since they tend to bleed off compression with the 117 lsa on the already low 9.5 compression of the 5.3. I would like to mill the heads some to get the compression around 10.8-11.0 I always run premium so between that and the polished chambers I dont think it should be a problem. Im not sure if I can mill the heads enough to get there though. Maybe milled heads and a thinner head gasket? Anyone know how much to mill? or pn# for thinner gaskets? I tried searching but didnt turn up much. Im on a limited budget (what I sold my hotside for $800) of course so Im looking for the biggest bang for the buck. Now onto the cam Im considering the tr224 /112 or the tr230 / 224 111 theres no emissions where I live so that is not an issue. I liked the lower lsa for the power down low. I didnt like the ZO6 cam since it falls off around 5500 and I'd like some more rpm out of my little motor well a little lope wouldnt hurt either. The motor shows 22in of vacuum at idle and the cam is definitley not carb friendly as far as tuning goes. I've got it pretty close now but since I decided not to go turbo the car is kind of a mess of mismatched parts as far as n/a performance. Any help or suggestions will be appreciated. Im listening.

 

personally, i would go at LEAST 224 or bigger, being that your car is light. maybe even around 228/230 .600" with a 110 or 112 LSA . should pull into the high 6K, around 7K with your setup.

i would swap gears though,maybe a 3.73 if you do any highway driving, 4.11+ if not.

as far as the heads, i beleive the norm is about .030" off the stock head, with a stock size gasket before running into PTV clearance issues... plenty of power can be had working stock heads with a good size bumpstick and LT headers.. possibly 360+ rwhp which should be very responsive in that light car...

 

Agreed a gear change is definitely in order. Some highway driving though so probably 3.73 possibly 3.55. Does anyone know approximately how much cr a .030 mill will net?

 

what are your plans for those turbo headers?

 

comtech has .40 gaskets BUT the GM MLS gaskets are really nice once you see them AND alot cheaper!

I would ask a engine builder or head guys, WCCH comes to mind about changes to the head and any PTV issues you might have from milling the head.

Your list seems nice, that should run good as listed I would not run to change the heads/cam.

I would get tuning and logging and go from a dialed in NA to bigger/better!

 

I sold them to a site member Blown1 is his name.

I spoke with Richard at wcch yesterday awesome guy btw. The heads are getting a .045 mill and Im still deciding on the cam. I'd like to use the ls6 springs I already have. I've narrowed it down to the comp

xr275hr high lift 222 224 566 568 114?

or

xr273hr xtreme rpm 220 224 530 534 114?

What do you guys think. I would think the springs would be fine for either?

 

I NEED to change the cam. It just doesnt work with a carb. 117.5 lsa is just not meant for a carb. Too much vacuum. I'm pretty sure 114 or 112 would be ok. Plus the ls6 cam quits around 5500 and I'd like some more rpm.

 

Custom grind

232/236 .576/.595 110+2

You'll need springs though.... Should be a nasty little cam in a carb'd 5.3L....seems you tend to think on the small side

 

Richard was telling me to stay in the 220 to 224 range to avoid ptv issues with the .045 mill on the heads. It is primarily a street car too. My brothers lq9 sports a hot cam and is pretty tough at 219 228 525 525 112

 

224/226? If you're going to mill that much, that's a good suggestion by Richard, he knows what's up