Has anyone stepped up this Olds 307 engine? I seen on a website of ways to make it run better but I want to try to run NHRA stock class with it for now. It has a roller cam and NHRA spec for the lift is .474 so alot of duration and probably a 107 lobe center is what it will take to get some performance out of it. The price that I have found for the cam is 345 from Ruben Racing but I have emails into Crower and Elgine for a quote. It might be cheaper to go hydraulic flat tappet and change lifters and pushrods. Feel free to add in all comments.
Everything I saw when looking at mods said find a 350 or 403. I have seen a few making around 300 hp and one making 6 ish. Those are high dollar deals. 250-275 is about tops without a crazy amount of work.
The only problem with that is you have to do what NHRA says to compete in stock class legally. They have casting numbers and a no porting rules. The head casting number has to be 22503317, the intake has to be 22500468 or 2253087. Rockers can be 1.6. You can go .080 over on bore but don't want to spend that money on this deal.
Good luck trying to get any performance out of what I like to call the "Gutless Cutlass Motor". Had one in an 86 Regal. It was like beating a dead horse. It literally died after 3500 RPM. Rated at a pathetic 140 HP.
I think it would be a waste of time and money to race that combo. I have messed with a 88 307 and it was not too bad after I added a set of ported 84 307 heads, and ported intake. Opening up the exhaust with headers and duals also helped however it was still pretty weak really.... Did manage to get 25 MPG with a big heavy Caddy, 2.41 gear, 2004R trans. If you really do end up building the 307 then max out the bore as you will need every bit of displacement, a custom cam, mill the heads to the min CC allowed, deck the block as much as they allow, headers. As you may or may not know the Buick 350 powered 74 Apollos run mid 11s with the stock intakes, heads, etc but it takes a lot of time and $....
The only reason for doing this is to run stock class plus have a daily driver. Sean I'm thinking about getting that 350 together and putting it in this car when I want to go fast. Do you think your headers will fit on the Regal with some tweaking?
If you can get away with offset grinding the crank from 3.385" to 3.610" stroke and only a .019" overbore,you might end up with something; 2.125 rod journal minus 1.888" rod journal(nascar take out rods from ebay) would be 3.622",but to make the pistons stay under the deck,make the stroke shorter @ 3.610",and this would allow the crank grinder to index grind the crank. http://www.ebay.com/itm/6-200-LENTZ...ts&hash=item1e6a6b0791&vxp=mtr#ht_4318wt_1092 The pin end will need to be honed out for a .943 pin,should be no problem,.943 - .929 = .014" which is only .007" per side plus proper pin clearance.(machine shop should know) With these pistons; http://www.summitracing.com/parts/uem-3519hc-1-0mm/overview/ If that engine has a roller cam already,you may be able to have it re-ground to a more proformance grind profile that is within the rules. Now you'll have 330 CID,if the rules will allow you to get away with that? Have fun!!
I've had a couple of those absolutely worthless engines. Find a good 350 and build that. Seriously. Oh, you want it to be the original. Good luck.
I finally got it home today and of course the fuel filter clogged on the pull truck when I left the dealership but it was acting funny before that. I took the paper filter out of the quadrajet and I couldn't blow through it after taking the check valve out. i emailed 3 crank grinders and no return emails. I think I will try Comp Cams next.I will start working on it tomorrow. The only reason I'm doing this is so I can run at the US Nationals. The other way is to build a 9.90 car. I also want to make this car a driver for now.
But if you use the 5A heads then you should use the matching iron intake. The Alum intake goes with the 7A heads you have on the car now likely.
It's got 7A heads but I can only use those casting numbers I showed you to be NHRA legal for class. Which are 7A maybe? ---------- Post added at 10:30 PM ---------- Previous post was at 09:46 PM ---------- Looks like neglected oil changes. 1 valve cover off and it looks yucky for 72,000 miles. I will take some pics tomorrow. Anyone got a olds magnetic pick up distributor?
The 7a heads had a roller cam and aluminum intake. Many people swap those parts on in place of the 5a stuff for reliability and weight savings. The biggest issue with that engine is the emission stuff which takes up alot of space and ads a bit of weight. Also those cars came with 2.78 or 2.93 gears. Swap in an 8.5" rear with 3.42 or 3.73 and it'll wake the car up alot. Then swap over to dual exhaust and get rid of the heat stoves and crap and it'll wake it up even more. Just about anything that you can do with a 350 you can do with a 307 since they're basically the same engine. Just remember that the performance difference from a 350 and a 307 will always be there. The same mods to both engines will give better results on the bigger motor. Of course by that same logic you should just go straight to the 455 :grin:
