307 power

[88ss408]

yeah i get what you are saying i would love to find a 350 rocket or a 403 but they are hard to find around here so thats why i thought to put my chevy motor in it but i just thought about it now i dont have motor mounts for that motor they are in my monte and car mounts around here are like impossible to find i am going to sick with the olds power and will buy so parts as i go and everything will interchange to the 307,350,403 right ?
intake ,headers,ignition system ect....

 

[beeterolds]

yeah i get what you are saying i would love to find a 350 rocket or a 403 but they are hard to find around here so thats why i thought to put my chevy motor in it but i just thought about it now i dont have motor mounts for that motor they are in my monte and car mounts around here are like impossible to find i am going to sick with the olds power and will buy so parts as i go and everything will interchange to the 307,350,403 right ?
intake ,headers,ignition system ect....

yup all your accessories will work. look at my sig. i squeezed a 455 in my cutlass. with no problems... the heads and intake from a 307 will fita 350/403 but dont use them...after 1985 the head flow really sucked...even a smog 350/403 will be way more fun....

if you do decide to go chevy power...ill take your frame mounts if u decide ud like to sell them.

 

[88ss408]

if i stay with my 88 block the lifters are bigger right ? so i will not be a ble to use another grind cam i looked at the H.O cam from the 442 and it will gain me 20 hp and then there is a couple of 455 cams and a 403,350 cam that looks good
but first is first i got to change the heads to the 5A along with the intake i will get headers because i need a new exhaust system
can all the EGR and smog stuff be taken off ? and my motor still run right ?
i am looking for about 200 hp it should not be to hard to do

 

[Silent viewer]

if you still have the computer running it all you need to yank it all and switch the carb to a non electronic one and get a vacume advance distributor, that should help the power...

 

[88ss408]

does anybody know the specs for a stock 307 ho out of the 442/ hurst olds ??

 

[marcar1993]

In a 3700 lbs car, 20 hp you WILL NOT feel. You'd be better off with a 350, of ANY year. I say, early 350; mill the heads 20 thou and get a better cam. Performer intake and a qjet.
Late 350, 73-80; flattop pistons, 0 deck the block, mill your heads 20 thou, port and polish, better cam, performer intake and a q jet.
Both can be run on your computer with bigger metering rods on the secondary side of the carb and opening the restriction so the air doors will open fully.

 

[buold]

Also olds is very different then a chevy power wise, Olds makes great TQ and for a g-body that comes in handy. We but my gbody on the dyno at school only made 132whp but the torque was 257. Thats what makes olds worth building.

 

[beeterolds]

442 lift was .440 .440 later engines used .904 diameter lifters.... companies make roller cams..like Lunati... with the heads you have from the factory..its not worth doing anything to the engine..other than swap

you want to feel some power? add 3.73 gears and true dual exhaust

 

[KrisW]

I want to see pics of this...cause i wanted to do this...but i couldnt cause of the size. while they both have the same chamber size he would have the same compression.. a lousy 7.9-8.0....
Bro i had a set of 1965 #3 330 heads... the chambers ARE WIDER Than the cylinder!! WONT WORK. THE cylinder is 3.8 wide the chamber is 3.9 it will run but he will have nasty quench and detonation issues...he better off leaving it alone. or searching for some 5A 1980-1984(442 in 1985) heads and installing 1.84 and 1.55 valves in them. Why do you think Mondello says not to do it?!?...its a known fact that the only head available for you to get any power from a 307 is the 5A head...all will physically bolt on...non will work effectively...even punched .060 over the 307s chamber Will NOT be large enough to compensate for the larger chambers of the earlier motors...Remember..all Olds motors with the possible exception of the 403..the bores matched the size of the chambers width... i run all my 307s as is..knowing there isnt much you can do to them... throw a set of true duals on it for starters and a 3.73 rear gear thats your best mods...stay away for hardcore engine mods....

I wish I had pictures. I was just a junkyard scrounger with old Motor Manuals to give me the specs I needed.

I wish YOU had just run those 330 heads like I did. They came from a 64 Cutlass 330 4bbl engine. They were awesome. I will openly admit that I did not measure everything to precision when running. I ran the heads, intake, exhaust and camshaft from that engine (I got it from the wrecking yard and it was stuck) on a 307 short block from 1983 or 1984 out of a Delta 88. It was just awesome. It's a shame you didn't even try; what did you have to lose? A few gaskets? 330 heads and 307 blocks are not that high worth to not experiment.

I have also run 455 heads on a 350. Again, I didn't have the problems that you are suggesting I'd have. With flat top pistons, I used "C" casting heads, a performer RPM cam, 1 3/4" long tube headers and a 750 Carter AFB out of the box. It was also just plain awesome. We used a Performer RPM intake and just port matched it. That was all.

Sometimes when you do things it works out. Theories are great, but sometimes you should just do it and see what happens.

As a last option, My 75 Omega had a 260. It is the only 260 I have seen that didn't have the really small intake ports like the 307's had. It had normal shaped, but smaller ports. Maybe those would be good for a 307 as well. I actually used small port 307 heads with the factory small port aluminum 4 barrel intake on it and it ran very, very well. It had a stock 403 camshaft from a junkyard trans am in it. Probably a horrible profile, but the little 260 liked it![/i]

 

[beeterolds]

I want to see pics of this...cause i wanted to do this...but i couldnt cause of the size. while they both have the same chamber size he would have the same compression.. a lousy 7.9-8.0....
Bro i had a set of 1965 #3 330 heads... the chambers ARE WIDER Than the cylinder!! WONT WORK. THE cylinder is 3.8 wide the chamber is 3.9 it will run but he will have nasty quench and detonation issues...he better off leaving it alone. or searching for some 5A 1980-1984(442 in 1985) heads and installing 1.84 and 1.55 valves in them. Why do you think Mondello says not to do it?!?...its a known fact that the only head available for you to get any power from a 307 is the 5A head...all will physically bolt on...non will work effectively...even punched .060 over the 307s chamber Will NOT be large enough to compensate for the larger chambers of the earlier motors...Remember..all Olds motors with the possible exception of the 403..the bores matched the size of the chambers width... i run all my 307s as is..knowing there isnt much you can do to them... throw a set of true duals on it for starters and a 3.73 rear gear thats your best mods...stay away for hardcore engine mods....

I wish I had pictures. I was just a junkyard scrounger with old Motor Manuals to give me the specs I needed.

I wish YOU had just run those 330 heads like I did. They came from a 64 Cutlass 330 4bbl engine. They were awesome. I will openly admit that I did not measure everything to precision when running. I ran the heads, intake, exhaust and camshaft from that engine (I got it from the wrecking yard and it was stuck) on a 307 short block from 1983 or 1984 out of a Delta 88. It was just awesome. It's a shame you didn't even try; what did you have to lose? A few gaskets? 330 heads and 307 blocks are not that high worth to not experiment.

I have also run 455 heads on a 350. Again, I didn't have the problems that you are suggesting I'd have. With flat top pistons, I used "C" casting heads, a performer RPM cam, 1 3/4" long tube headers and a 750 Carter AFB out of the box. It was also just plain awesome. We used a Performer RPM intake and just port matched it. That was all.

Sometimes when you do things it works out. Theories are great, but sometimes you should just do it and see what happens.

As a last option, My 75 Omega had a 260. It is the only 260 I have seen that didn't have the really small intake ports like the 307's had. It had normal shaped, but smaller ports. Maybe those would be good for a 307 as well. I actually used small port 307 heads with the factory small port aluminum 4 barrel intake on it and it ran very, very well. It had a stock 403 camshaft from a junkyard trans am in it. Probably a horrible profile, but the little 260 liked it![/i]

There are 3 major mods needed to get early 330 heads on a late 350 403 or ha 307 what did u do? 3 mods..and please dont tell me u just bolted them on..cause if in fact this did work..it is not an easy bolt on, there are a few modifications you have to do including machining.. Im not presenting you with theories...its tried and true...it may run..but very very poorly...its not a good recommendation either way..

Why should anyone waste their time with this swap your totally misinforming people here... its like putting 350 Chevy heads on a 267...do u ever hear of people doing that? NOOOO...for the same reason...the bores are too small an the chamber is too wide!! Motor manuals tell you what? they dont list serial numbers of engines... you need to know what engine is in the car..then they give you the specs about it...they dont tell you how to identify...i work at a shop we have a few dozen of them books...but then again to a novice they may be valuable.

The stock 403 cam profile is close to a 260..it may have just a lil more lift (.400 .402 187-200 dur. @ .050) just because it came out of a larger engine doesnt make it better! but you wouldn't see any gains...the only heads you can use on a 260 are 260 heads like the 307. The 260 #10 heads are what you are referring to cause the 260(late) 2A heads are really really bad. Again the 260 engine must use 260 heads. the COMBUSTION CHAMBERS ARE TOO WIDE on any other engine..

260 heads on a 307 look good on paper...the early ones you refer to have better ports than the 6A 7A heads...but the valves are tiny...while youll gain compression youll choke the engine with crappy flow.

455 heads on a 350 wont get you over 9.1 compression unless u mill the block and heads...im not saying its a bad idea...it will work but why? when u can get more out of 5 or 6 heads.using 455 heads is a common swap with 403 guys that can afford E brock heads....this is more practical to do...if you race....you will lose a large amount of low end torque...but gain a lot on the top end..if u have a cam and the compression to support it..