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While I am awaiting delivery of my newly purchased 68 Cutlass S Convertible (more on this later), I am requesting advice on short term and long term engine modifications.
The car has about 140K miles on it, but it appears that the numbers matching Rocket 350 has been gone through at some point. The car is a 350 2bbl, Jetaway, PS, PB, AC with 2.78 open rear end. I intend to upgrade the drivetrain for fun, spirited driving, but nothing crazy. I intend to swap the transmission for either a TH350 or 200-4R and swap the rear end for a 3.08 or 3.23 Posi.
As for the engine, the block number matches the VIN, but I do not know the casting number. The heads are #5 for sure. The reason I am thinking that someone has gone through the engine is because of a few things. First, it is painted red (why?) but more importantly, it seems to run fine. There is no smoke coming from the exhaust either at startup or when running. Also, with the breather off of the valve cover, there appears to be no noticeable blow-by.
The car has been sitting for about five years, but it is drivable. It needs a tuneup, and the carb needs to be rebuilt. Instead of fiddling with the 2bbl, I was thinking that the easiest thing to do would be to go ahead and install an Edelbrock Performer RPM intake and 4bbl carb, change the fluids and spark plugs and possibly convert to HEI.
Long term, here is what I am thinking of doing to the engine:
Edelbrock Performer RPM (7111)
4bbl carb of EFI (Quadrajet?, Holley?, Holley Sniper?)
New cam - Either Erson cam, E540121, 214 duration & 0.478 lift or Crane Cams, PowerMax 804542, 216/218 at 050, 0.272/0.284 duration, 0.484" / 0.512" lift
Roller timing chain
Speedpro L2320F or L2321F (aiming for 9.5:1 to 10:1)
HEI - MSD? Other?
Maybe some head work with bigger valves
Dual exhaust
Unsure about headers
As soon as I get the car, I intend to check the compression on each cylinder. If they are all good, I will probably just make the short term changes (new intake, carb, plugs) to make it more reliable while I get other work done (brakes, transmission, rear end, body work, etc.) Changing the intake will also let me peek inside the engine to see how good or bad it looks. If the compression is bad, I will probably just pull the engine and start the rebuild there.
My questions for you:
1) Does this plan make sense, or should I just plan to yank the engine and start there?
2) What carb would you recommend based upon the other specs mentioned? I have rebuilt Q-jets, but I have more experience with Holleys.
3) Thoughts on the two cams?
4) Thoughts on the overall specs?
Thanks in advance!
Last edited by NTXOlds; October 26th, 2020 at 06:04 PM.
Reason: CORRECTED TYPOS
you'll get all kinds of advice from tune it and go to making a total rebuild your first priority.
here's what my '72 motor looked like inside after a reported original 54k miles and it still ran GREAT - the car itself was clean/solid enough to legitimize the miles but maybe from LACK of use the motor didn't fare as well - I pulled it and went all thru it for a total rebuild/performance upgrade.
Ultimately went with the MSD billet electronic ignition instead of Pertronix for better reliability. Speed Pro flat-top pistons .030 with rebuilt stock rods, 2200-2500 torque converter on a full trans rebuild and pretty much all the other things outlined in my earlier post. Go all the way thru the thread for additional pics of engine and suspension build progress, etc. roughly 24 total pics.
may be your best bet to determine its running condition after a simple tune-up and save it for last while you stockpile parts, if solid enough to get you through the other projects, and if they're otherwise you preferred priority.
Last edited by 70sgeek; September 13th, 2020 at 03:54 PM.
Change the gear first, I’d do no less than a 3.42 with the 200-4R.
Buy a better piston than the L2320, old tech.
i made 410+ with 7a heads, Mahle pistons and an RPM with a QF750 Slayer carb. BUT you need to tune it with a wideband O2 in order to do it right.
Best of luck in your project.
Last edited by cutlassefi; September 13th, 2020 at 08:50 PM.
Mark's (EFI) right as to the pistons being old tech - I woulda probably changed that if I had spent more time researching that option. I went with a relatively conservative upgrade cam to stay safe on vacuum and ability to run my a/c whenever FL heat demands..
I am still planning a 455 motor build for my ragtop's future and still need to catch up with Mark to lay that out but until we connect, I'm pretty happy with how the 350 turned out - tough little motor which still runs just under 3k rpm at 70 mph on the 3.08 gears.
If the engine checks out OK, then just install a 4-bbl intake and carb and enjoy it as is until there is a need to do engine work.
As for the rear gears, your car would have come from the factory with an O-Type rear, which is a 12 bolt cover and a 10 bolt ring gear. Gear choices are limited and very few aftermarket gears are available, and if you have the typical 2.56 gear ratio, then you would need a different carrier for the 3 series gears, either Gm or aftermarket. But the rear gear change is without a doubt the best bang-for-the-buck performance improvement you can make, and it will work well with any future engine performance upgrades.
Change the gear first, I’d do no less than a 3.42 with the 200-4R.
Buy a better piston that the L2320, old tech.
i made 410+ with 7a heads, Mahle pistons and an RPM with a QF750 Slayer carb. BUT you need to tune it with a wideband O2 in order to do it right.
Best of luck in your project.
Thanks, cutlassefi, I was hoping to hear from you.
I have read that the Mahles are good, but can you please explain the advantages over the Speedpros?
What are your thoughts on the cam choices for drivability and fun?
Mark's (EFI) right as to the pistons being old tech - I woulda probably changed that if I had spent more time researching that option. I went with a relatively conservative upgrade cam to stay safe on vacuum and ability to run my a/c whenever FL heat demands..
I am still planning a 455 motor build for my ragtop's future and still need to catch up with Mark to lay that out but until we connect, I'm pretty happy with how the 350 turned out - tough little motor which still runs just under 3k rpm at 70 mph on the 3.08 gears.
Thanks! Sounds like you have a really nice car with a good setup. Obviously, a 455 will be a lot of fun, too.
If the engine checks out OK, then just install a 4-bbl intake and carb and enjoy it as is until there is a need to do engine work.
As for the rear gears, your car would have come from the factory with an O-Type rear, which is a 12 bolt cover and a 10 bolt ring gear. Gear choices are limited and very few aftermarket gears are available, and if you have the typical 2.56 gear ratio, then you would need a different carrier for the 3 series gears, either Gm or aftermarket. But the rear gear change is without a doubt the best bang-for-the-buck performance improvement you can make, and it will work well with any future engine performance upgrades.
Thanks! I agree. If I can confirm that the engine is sound, I will upgrade the brakes to front disk first and then work on the transmission and rear end. That should give me a good idea how the car will feel and drive when I refresh the engine. To me, this is the best case scenario.
Honestly a 2004R with a 2200 to 2500 stall and either 3.42 or 3.90 gears, the only 2 ratios available new, would be night and day. Do a compression test, see how healthy the motor is. Of course hard to say if new pistons were installed, stock would be around 9 to 1 compression. That would work well with the Erson cam. That and a 4 bbl along with dual exhaust would be good upgrades on a healthy motor.
Last edited by olds 307 and 403; September 13th, 2020 at 06:53 PM.
Honestly a 2004R with a 2200 to 2500 stall and either 3.42 or 3.90 gears, the only 2 ratios available new, would be night and day. Do a compression test, see how healthy the motor is. Of course hard to say if new pistons were installed, stock would be around 9 to 1 compression. That would work well with the Erson cam. That and a 4 bbl along with dual exhaust would be good upgrades on a healthy motor.
Thank you! That sounds like a very good combination that would be fun to drive without feeling like a race car.
I think that I have read every thread regarding the Edelbrock Performer vs Performer RPM intake differences, and I am thoroughly convinced that I would be better off with the regular Performer for my street build.
That said, without starting any kind of flame war, what do you think is the MINIMUM setup (Compression, Cam, Carb, Converter, etc.) for really getting an advantage out of going with the Performer RPM over the standard Performer?
I think that I have read every thread regarding the Edelbrock Performer vs Performer RPM intake differences, and I am thoroughly convinced that I would be better off with the regular Performer for my street build.
That said, without starting any kind of flame war, what do you think is the MINIMUM setup (Compression, Cam, Carb, Converter, etc.) for really getting an advantage out of going with the Performer RPM over the standard Performer?
again, many different opinions - I'm running approx 9.5:1 CR, E-brock 2711 Performer intake with an 800cfm electric-choke Qjet built by Everyday Performance based on my overall motor specs. For a cam I'm running the Howards Street Performer cam and springs (I believe the p/n may be in my earlier thread) but I also know Mark has other cams he can suggest. Converter depends a lot on your gearing but I think something in the 2200-2500 stall may be the most frequent suggestion you'll get.
Good ignition timing will also notably enhance your street performance.
FYI, I installed a Performer RPM in place of a Performer 350 on my car and it appeared to run much better. I had posted detailed info about this on another Olds web site but that info was lost in a crash, and I don't remember all of the details as it's been a decade or more now. Anyway, if you are doing an intake swap, I say go for the Performer RPM over the Performer 350. Unless you find a regular Performer for a "can't pass it up price", that is.
If going to a 4BBL and doing some "spirited" driving, check the timing chain for stretch and to see if the nylon cam gear is still in there. This could be done with a borescope through the fuel pump mounting hole. If the nylon gear is still there consider replacing the timing set.
FYI, I installed a Performer RPM in place of a Performer 350 on my car and it appeared to run much better. I had posted detailed info about this on another Olds web site but that info was lost in a crash, and I don't remember all of the details as it's been a decade or more now. Anyway, if you are doing an intake swap, I say go for the Performer RPM over the Performer 350. Unless you find a regular Performer for a "can't pass it up price", that is.
Thanks. Your setup seems to be in the ideal range for a Performer RPM.
If going to a 4BBL and doing some "spirited" driving, check the timing chain for stretch and to see if the nylon cam gear is still in there. This could be done with a borescope through the fuel pump mounting hole. If the nylon gear is still there consider replacing the timing set.
Good luck!!!
Thanks, Sugar Bear! I will be replacing the timing chain for sure the first time the engine comes out.
I got my Cutlass back from the transmission shop this week, and as many of you suggested, the TH350 makes the car drive so much better. I am still experiencing some fueling issues, but it is still very drivable.
Since the engine is painted red even though it is a numbers matching 68 350, my guess is that it has been rebuilt at some point. The fact that the engine appears to be stock with the 2bbl carb makes me think that very little was done to it other than perhaps a rebuild to stock specs. The engine feels reasonably strong and it doesn't burn oil.
I decided to do a little investigation into this, and I used a borescope to check out a piston. Here are a couple of the photos. From what I can tell, these look like the factory-style pistons for the 9:1 2bbl engine. Looking at the edge of the piston, however, I did not see any kind of notch. This piston was smooth around the entire perimeter except for one area where the piston looks a little damaged to me.
My questions for you are: 1) Does the dishing look like the 9:1 piston to you? 2) Did factory pistons all have some sort of notch in the edge? 3) If so, do you think that these are likely cast .030 replacements? 4) Does this look like damage to the edge of the piston?
I also ran a quick compression test on this cylinder only, and it came out to 130-135 psi both before and after a tablespoon of oil.
But since it does not have any kind of notch along the outside (no half moon, no V cut), I am guessing that this is an older aftermarket cast piston, probably .030 over.
I am still curious of that is damage along the edge.
I doubt those are 68 pistons, they look like my 72 pistons with the huge 24cc dish, your motor will be very low compression, no where near 9-1 if there the same.
I doubt those are 68 pistons, they look like my 72 pistons with the huge 24cc dish, your motor will be very low compression, no where near 9-1 if there the same.
I was wondering that, but the diameter of the dish section looks bigger on your piston than mine. In other words, the non-dished section on yours looks quite a bit narrower to me.
On the post that I linked, the visual difference between the "1970 9:1" and the "1972 8:1" looks pretty dramatic although elsewhere in the post it states that the diameter is only supposed to be .04" difference.
Does it look like that to you, too?
I guess what we do know is that the engine was definitely not upgraded to a higher compression piston whenever someone opened it up.
Last edited by NTXOlds; December 8th, 2020 at 03:41 PM.
I was wondering that, but the diameter of the dish section looks bigger on your piston than mine. In other words, the non-dished section on yours looks quite a bit narrower to me.
On the post that I linked, the visual difference between the "1970 9:1" and the "1972 8:1" looks pretty dramatic although elsewhere in the post it states that the diameter is only supposed to be .04" difference.
Does it look like that to you, too?
I guess what we do know is that the engine was definitely not upgraded to a higher compression piston whenever someone opened it up.
Here is the information that I have archived for the various pistons in the 350 engines:
1968-1970 350 4bbl: 6cc dish .077" deep x 2.54" diameter.
1968-1970 350 2bbl engines, 1973-1976 all: 14cc dish .130" deep x 2.88" diameter.
1971-1972 all: 23cc dish .215" deep x 2.92" diameter.
So while you are correct that the diameter is .040" different, the depth is .085" different. That is very significant.
Here is the information that I have archived for the various pistons in the 350 engines:
1968-1970 350 4bbl: 6cc dish .077" deep x 2.54" diameter.
1968-1970 350 2bbl engines, 1973-1976 all: 14cc dish .130" deep x 2.88" diameter.
1971-1972 all: 23cc dish .215" deep x 2.92" diameter.
So while you are correct that the diameter is .040" different, the depth is .085" different. That is very significant.
Thanks for sharing the reference. You are absolutely right. The depth is very different. To me this does not look as deep either. It is definitely not as shallow as the 6cc.
I was wondering that, but the diameter of the dish section looks bigger on your piston than mine. In other words, the non-dished section on yours looks quite a bit narrower to me.
On the post that I linked, the visual difference between the "1970 9:1" and the "1972 8:1" looks pretty dramatic although elsewhere in the post it states that the diameter is only supposed to be .04" difference.
Does it look like that to you, too?
I guess what we do know is that the engine was definitely not upgraded to a higher compression piston whenever someone opened it up.
yup, 4 sure not flat tops, hard to read your pic due to the carbon, but maybe it is the 14cc pistons.
yup, 4 sure not flat tops, hard to read your pic due to the carbon, but maybe it is the 14cc pistons.
I agree. The carbon makes it hard to tell. Using Photoshop, it almost looks like there are some numbers on the face of the dish. I may try examining a couple more pistons to see if I can find one that has less build up.
I also wonder if the "damage" on the lower right edge might just be carbon build up, too.
I also wonder if the "damage" on the lower right edge might just be carbon build up, too.
I’m thinking the same or could you have detonation issues.[/QUOTE]
That certainly was my concern. I could not see any obvious damage to the cylinder itself, and I have not experienced any detonation myself running on pump gas. That said, I have only had it since October when the temps here in Texas have been pretty mild.
I think I am going to bite the bullet and yank the engine over the holidays.
I’m thinking the same or could you have detonation issues.
That certainly was my concern. I could not see any obvious damage to the cylinder itself, and I have not experienced any detonation myself running on pump gas. That said, I have only had it since October when the temps here in Texas have been pretty mild.
I think I am going to bite the bullet and yank the engine over the holidays.[/QUOTE]
I looked at the pix again. In the second photo the top of the piston appears to be eroded. It’s hard to tell. Carbon will look like fluffy deposit’s on the top of the piston. Detonation will damage softest metal in the combustion chamber. Usually the piston. It may start as erosion. It can progress to cracks or even a hose in the piston. If you are intent on engine disassembly for rebuilding then go for it. If your only concern is piston damage I suggest cleaning the combustion chambers with a top engine cleaner, then re-inspect with the bite scope. I had good success AC Delco XP66 though I’m not sure if it is still available. Sea Foam may be a viable alternative. Based on what you see you can make a better determination to the extent of repair and budget needed.
Keep us posted of your project.
Best to you.
That certainly was my concern. I could not see any obvious damage to the cylinder itself, and I have not experienced any detonation myself running on pump gas. That said, I have only had it since October when the temps here in Texas have been pretty mild.
I think I am going to bite the bullet and yank the engine over the holidays.
I looked at the pix again. In the second photo the top of the piston appears to be eroded. It’s hard to tell. Carbon will look like fluffy deposit’s on the top of the piston. Detonation will damage softest metal in the combustion chamber. Usually the piston. It may start as erosion. It can progress to cracks or even a hose in the piston. If you are intent on engine disassembly for rebuilding then go for it. If your only concern is piston damage I suggest cleaning the combustion chambers with a top engine cleaner, then re-inspect with the bite scope. I had good success AC Delco XP66 though I’m not sure if it is still available. Sea Foam may be a viable alternative. Based on what you see you can make a better determination to the extent of repair and budget needed.
Keep us posted of your project.
Best to you.[/QUOTE]
Thanks for the advice. Going back to the original premise, since the engine is painted red and since the pistons do not appear to have any kind of notch along the edge, it is almost certain that the engine has been rebuilt at some point in the past. It runs well and doesn't seem to burn any oil, so other than cosmetics (the exterior of the engine is really dirty), it seems wasteful to rebuild the engine if it is not really necessary.
I suppose I could just pull the intake and heads and measure the wear on the cylinders. If it is fine, I could get the heads reworked, bolt on some goodies like a new intake and carb and just put it back together. I think if I go through the trouble of pulling the engine, I might as well do a full rebuild.
Drive it and enjoy it. If you desire to really get into it, then just simply get a hold of a set of 5 or 6 casting cores a block and a crank. simple enough and cheap. Start your new build with the acquired cores. No down time. When you think about it, you'll be changing just about everything anyway, but the cores.
Drive it and enjoy it. If you desire to really get into it, then just simply get a hold of a set of 5 or 6 casting cores a block and a crank. simple enough and cheap. Start your new build with the acquired cores. No down time. When you think about it, you'll be changing just about everything anyway, but the cores.
I have decided that since I have two solid weeks off for the holidays and not much else to do, I am going to do the following:
1) Perform a leak down test. If it checks out fine, I will move on to #2. If not, I will pull the engine and start a rebuild.
2) Pull the carb and intake. If the valley between the cylinders looks terrible, like it has decades of sludge, I will just pull the engine to start a rebuild. If not, I will move on to #3.
3) Replace the 2bbl intake and carb with an Edelbrock Performer and Holley Street Warrior 4bbl. It may not make a huge difference on performance over the 2bbl, but I am much better at tuning Holley carbs.
4) Hook up the TH350 kick down cable to the carb.
This will give me a chance to really experience the drivability of the engine as is with the new TH350. I have also sourced a 3.42 posi carrier and gears from another member here. Once I get that installed, the drivetrain should be more or less done. I will have a much better idea of how much extra power I want when I finally get around to a full engine rebuild.
Part of me is still considering just pulling the engine immediately and to go ahead and swap out the cam & lifters, put in new timing gears, new water pump, new intake and carb but leave the heads and cylinders alone. Back in the day, I am confident I could do this in a weekend, so I hope I could get it done over the course of two weeks.
3) Replace the 2bbl intake and carb with an Edelbrock Performer and Holley Street Warrior 4bbl. It may not make a huge difference on performance over the 2bbl, but I am much better at tuning Holley carbs.
I was just driving my car and it took a while for the choke to warm up and disengage. With the front 2 barrels only, it felt like a 1975 Pinto, but after it warmed up, I was able to leave 185 feet of fresh blacktop on the roadway (seriously, I went back and measured it). So unless your 2bbl carb is significantly larger than the front half of a QJet, you are going to notice an increase in power with the 4bbl over the 2bbl.
I was just driving my car and it took a while for the choke to warm up and disengage. With the front 2 barrels only, it felt like a 1975 Pinto, but after it warmed up, I was able to leave 185 feet of fresh blacktop on the roadway (seriously, I went back and measured it). So unless your 2bbl carb is significantly larger than the front half of a QJet, you are going to notice an increase in power with the 4bbl over the 2bbl.
I am definitely expecting some performance improvement if only from more consistent fuel delivery than my inconsistent 2bbl, but I am trying to keep my expectations under control since it likely has the factory cam and probably lower compression than the factory 9:1.
I’m thinking the same or could you have detonation issues.
NTXOlds, my first car 1967 330 2BBL with by the book timing, did not like anything lower than 91 Octane. I Always thought it was the low compression version... After a little while of dancing around with different octanes I settled on Ultra 94, she loved it. For some of us the cars are toys for others daily drivers. Either way I would never skimp on gas. Modern gas is crap compared to what our cars were born into.
Originally Posted by NTXOlds
I am definitely expecting some performance improvement if only from more consistent fuel delivery than my inconsistent 2bbl, but I am trying to keep my expectations under control since it likely has the factory cam and probably lower compression than the factory 9:1.
"The car is a 350 2bbl, Jetaway, PS, PB, AC with 2.78 open rear end" All mods recommended will make a drastic difference. Your factory setup is just about as sleepy as it gets back then. If your engine checks out, your rides a perfect candidate for the starter go package. 4BBL, dual exhaust, more gear/gears.
I've seen enough road tests to come to the conclusion that a 2 speed transmission leaves up to 50 HP on the table vs a 3 speed. Quadrajet, headers, THM350 , 3.42 rear, and the car will be night and day different. 4BBL and headers ideally can add 60 HP. Lets take off 10 for wear and tear. So potentially 100 HP improvement in a sense with a drivetrain better suited to take advantage of it. You cant go wrong.
NTXOlds, my first car 1967 330 2BBL with by the book timing, did not like anything lower than 91 Octane. I Always thought it was the low compression version... After a little while of dancing around with different octanes I settled on Ultra 94, she loved it. For some of us the cars are toys for others daily drivers. Either way I would never skimp on gas. Modern gas is crap compared to what our cars were born into.
"The car is a 350 2bbl, Jetaway, PS, PB, AC with 2.78 open rear end" All mods recommended will make a drastic difference. Your factory setup is just about as sleepy as it gets back then. If your engine checks out, your rides a perfect candidate for the starter go package. 4BBL, dual exhaust, more gear/gears.
I've seen enough road tests to come to the conclusion that a 2 speed transmission leaves up to 50 HP on the table vs a 3 speed. Quadrajet, headers, THM350 , 3.42 rear, and the car will be night and day different. 4BBL and headers ideally can add 60 HP. Lets take off 10 for wear and tear. So potentially 100 HP improvement in a sense with a drivetrain better suited to take advantage of it. You cant go wrong.
Yes, it is fun to modify the car one thing at a time so that you can see what difference each change makes. So far the dual exhaust makes it sound better, and the TH350 made a big difference in the "fun to drive" department.
I should have the 3.42 posi in hand in a week or so, and I am likely to have the new intake and 4bbl Holley installed sometime next week. I will probably swap the coil out for the MSD Blaster 2, relocating it to the firewall since I am changing the intake. Other than switching to electronic ignition or adding headers, I think that will be as good as it can get without a new cam, head work, etc.
Yes, it is fun to modify the car one thing at a time so that you can see what difference each change makes. So far the dual exhaust makes it sound better, and the TH350 made a big difference in the "fun to drive" department.
Awesome, believe it or not you already reduced your cars elapsed time if you ran a 1/4 mile by 1 full second.
Originally Posted by NTXOlds
I should have the 3.42 posi in hand in a week or so, and I am likely to have the new intake and 4bbl Holley installed sometime next week. I will probably swap the coil out for the MSD Blaster 2, relocating it to the firewall since I am changing the intake.
The 4BBL alone, drops you another full second.
Originally Posted by NTXOlds
Other than switching to electronic ignition or adding headers, I think that will be as good as it can get without a new cam, head work, etc.
Now your in icing on the cake territory.
For reference here are Automobile Catalogs simulations for your car and the like with factory mods.
1968 350 2BBL 2SP = 17.4 in the 1/4 mile
1969 350 2BBL 3SP = 16.4 in the 1/4 mile
1969 350 4BBL 3SP = 15.4 in the 1/4 mile (i personally ran a 15.5 with my 120,000 mile 69 weighing 125 LBS more than Auto Cats version, the weight difference alone makes us dead even so these numbers are absolutely attainable)
All above are with standard 2.78 rear... You are missing the 4BBLs compression (-10 HP gross or about - 7 HP net) but you can make that up in other ways. Performance mufflers and a balance tube may do it. Performance mufflers and a X pipe should do it.
Headers, better converter, 3.42s maybe you see a 14.4
You may not feel it so much just yet. But the gain from the dual exhaust is absolute. You may have to really get on the car to feel/see it in our power range. For example in 1971 Old's 4BBL 350 saw the 20 HP gain when going from single to dual exhaust at 4000 RPM and 4400 RPM. Below is a Joe Mondello fully worked 400 HP Old's 350s flywheel dyno chart. Far more powerful than our engines by probably 100 HP but still a good way to see how the incremental HP gains in power occur as the engine is being wrung out.
The lower line when going left to right is the HP, notice the difference in power between 4000 and 4400 RPM. Joe's engine goes up 43 HP. His engine is so much more aggressive and powerful than ours that he is past our peak HP by 3800 RPM. I guess what I am getting at is that our cars need to have an aggressive set up to take advantage of any power gains and driven accordingly to see the improvement. Stockish or fully built. And you are clearly going in the right direction in that department.
I went from 2.56 to 3.42 and gained .6 in the 1/8 mile. A mild cam swap will work well since you are close to 9 to1 compression, probably need a timing chain anyways. A 2000+ stall with also help a lot. I had your basic motor, a 76 350 with slightly milled #6 heads with a bigger intake valve and the bowls opened, 214/214 cam, Sanderson shorties and 2.5" dual exhaust, 2300 flash stall and 2.78 open rear. I could do a 1/4 block burn out. The day before I took it to the 1/8 mile my Daughter fried the trans. I should have took it with just first and second gear in the 2004R. It probably would have ran mid 9's in the 1/8, not fast but a definite improvement over stock.
September 13th, 2020, 02:53 PM
