Inliners International Forums General Discussion Engines My 230/250 Build

There is a way to get around the overheating issue during the build on the overdrive transmissions. My converter builder described it to me, but I don't build transmissions. My brother does, and he did it to mine. I'll get the info and put it up here.

That would be good to know what is done to keep them from overheating. Mshaw 230, are you experiencing any trans heating problems so far? Do you have a trans temp gauge? Because he is running a looser converter I would think the trans would run hotter. Does anyone here know if someone makes a gearset for a th 350 where both first and second gears are lower? Like 3.06- 1.75-1 or something simular? Jay

Check with Jim Beaty at ATI

Its called a 4l60...

4L60E, 3.06, 1.62, 1.00, 0.70

If that's what I have to do I'm willing to go there.

IMO having a low first gear set is not the way to go even if those calculations seem to show an advantage.
They make a low gear set for a Th350 2.75 first gear set that would has less of a drop I the 1st to 2nd gear shift but my friend that build transmissions said that gear set is not that strong.
MBHD

A non-lockup looser converter and numerically low e.g. 3.0:1 diff gears are a problem waiting to happen. The converter will be in slip - which generates heat.

Best solution - ditch the non-lockup converter.

That s why I was wondering about the 200-4R in the Camaro. It's a non-lockup unit with overdrive and a 3.08 axle ratio. When running in OD the converter could be in "slip mode" which would build heat pretty fast. It may be ok depending on converter design. According to Hughes, they can make me a non lock up converter for my TH 350 that would have a little more stall speed but feel "tighter" on the freeway when up to speed. I have not done this as of yet because I haven't decided on what trans I am going to end up with. Trust me I am the last person who would claim to be any kind of trans expert. Jay

I really don't know much about the lighter duty autos. Back in the day it was all small block V8s, TH400s, TH350s, TH700s, T10s, and Muncies that people talked about. So I really don't know much about their little brothers until I got my 3spd Saginaw and started learning about how the Sags are put together. I'd like to learn more about the application of 200s. Especially what they will fit into with modifying the sheet metal of the drivetrain tunnel. I know the 700s will fit in a 3rd gen Camaro, but not earlier Camaros or Novas.

The 2004r is roughly the same package as a TH350. It's more expensive to build than a 700r4 but it can be built to take a beating.

Oh, ah, interesting. So they took the TH350, added an OD (and lockup converter?) and called it the TH200r4. So it's identical to the TH350 otherwise? Is it the same length, so it can be used with the factory driveshaft? I thought the TH200r4 was a weaker tannie than the TH350 because of the 200 number. But the 350 stands for taking up to 350 ft-lbs of torque, while the 400 is for 400 ft-lbs (although we know both can handle more than that even in stock configuration). That should be plenty for a naturally aspired 250 or even 292 inline?

That depends on the flavor of 2004r you choose. The stock ones from a GNX are quite a bit stronger than, say, a Buick LeSabre.

The driveshaft is the same length as the powerglide and TH350. You'll need to modify the crossmember.

You can see the modified crossmember I'll be using here:



I also had to get new linkage, a TV cable, and, of course, a new bezel. If you have a floor shifter you might need to do more.

For wiring you'll need a keyed power source and a new switch or relay for the brake light to disengage OD. I haven't gotten that far yet.

May also need a new dipstick or modify the old. Mine, luckily, already has a correct one.


You can see the body isn't huge. Mine is built for 700hp. I think it'll hold up just fine...

The 2004R is NOT derivative of the TH350!!!

It was developed from the TH200 three speed automatic that was developed for lighter vehicles and originally placed behind V6 engines and the smaller V8s in the 4.7 liter range. The overdrive version is slightly heavier built, but will not measure up to the 700R4 and 4L60E as far as heft and strength.

It is NOT the overdrive that needs to be disengaged! The lockup clutch in the torque converter is what must be de-activated. With proper circuitry, (which can be found by searching the internet) you can make this work. There is also a hydraulic circuit in the valve body that can keep the converter clutch from being activated in first and second gear.

In a light weight car, the 2004R can handle pretty good horsepower, given the proper modifications and some better aftermarket parts.

Ah, I got confused on that answer. Looking back at the 2nd Gen Camaro, after 1973 the only auto used in the Camaro for everything including inlines was the TH350 except:

1980 - 229cid - Chevy 90/V6 - TH200 (but CA Buick 231cid got the TH350)
1981 - 229cid - Chevy 90/V6 - TH250 (same gearing as the TH350, a variant?, CA Buick is TH350)

Then they lightened the Camaro in 1982 third gen, and the inline returned as a 151cid L4:

1982 - L4/60-V6/305 - all TH200c
1983 - L4/60-V6 only cars with carbs - TH200c (all others got the TH700r4
1984 on - all engines - all TH700r4

For the Saginaw in the Camaro after 1977:

1978/9 - L6 w/ 3.5 3spd - V8 w/ 2.85 4spd (except Z28)
1980 - 229cid Chevy w/ 3.5 3spd - 305 w/ 2.85 4spd
1981 - 229cid Chevy w/ 3.5 3spd
1982 - All Sag 4spd but 3.5 w/ L4, 3.6 w/ V6, 3.42 w/ LG4, 2.88 w/ LU5
1983 - Sag 4spd in L4 & V6 w/ 3.5
1984 - Sag 4spd in L4 w/ 3.5 (end of the line for Sag 4spd
1985/6 - L4 still available but with 5spd

The L4 in the 3rd gen Camaro is pretty rare to find. I'm not any were really produced after '83 but they were still listed as the base engine. Midway thru '83 they went from carbs to fuel injection for it. Would interesting build one of those in a 3rd gen Camaro if you can find one.

A 4l60 will bolt in place of a th350 - with minor mod's - in some cases none.

Depending on the vehicle - the cross member might have to move rearward ~ 1/2" and the driveshaft might need to be shortened.

I have had to do no mods or both to mechanically do installations.

Capacity wise a stock 4l60 wins hands down over even a decently built 200r4. The 200 series clutch just don't have the surface area.

For $600 you can buy all the aftermarket parts needed to build a 400 #/ft capable 4l60. Not many inliner's here are making more than that torque output.

If your making BIG power - put a 4l80 in it and forget it. They are a th400 + and extra planetary gear set to get OD.

The 700R4 , 4L60E , will not bolt right in replacing a TH 350 Powerglide, M20, M21, trans etc you would need a different length driveshaft.

MBHD

If you are removing the TH350 with the long tailshaft housing, the 700/4L60 will go right in. Even uses the same slip yoke! I swapped in enough TH350s for these when they first came out to sink a canal barge!! They were suffering from the new design bugs that plagued many new transmissions back then and folks paid good money to go to the more reliable TH350. We swapped many into light pickups back then too.

For about three years, I spent ten hours a day under cars and trucks making these swaps and helping to R&D the new transmissions for the aftermarket industry. For a while, the brackets for the crossmember were still there on the frame of the GM cars and trucks to make the exchange even easier!!

The only thing required to swap in the 700/4L60 is to relocate the crossmember and shifter cable and replace the detent cable with the appropriate one. If you are replacing a short 350 or 'Glide or one of the 4spds your local driveshaft shop can shorten the shaft for "real cheap" and even the slip yoke can be reused.

If you're replacing a stick, (manual) tranny, you will, of course, have to find the appropriate replacement gear selector assy.

That was my understanding from way back when, was that the 700 was indeed longer than the TH350 that 2nd Gen Camaro's used, and there was no way to fit it in the drivetrain tunnel without modifying the sheetmetal of the floor. I would presume the Nova was the same. The 3rd gen Camaros came ready to fit it, and it was the only real performance transmission for the 3rd gen Camaro, as the 5spds were too light duty. My guess would be the 2nd gen Camaro used the shorter TH350 then.

Don't know about anything other than first gen camaros here. It's much longer than the PG or TH transmissions used on first gens.

The 700 is NOT a bolt-in for first gen Camaros. The 2004r is easier. Just need to either modify the crossmember or get a new one, adapt a TV cable, get new shifter linkage, and wire it up. It'll fit right in after that. Driveshaft length does not change.

I was mistaken on the TH350 to 2004r. Thought they were basically the same since they swap so easily.

From Wiki:

THM200-4R[edit]
For the 1981 model year, the 200-4R (sometimes called 200R4) was introduced. The components which were prone to failure in the THM200 were improved, and this transmission was used with high-power applications — primarily the Buick Grand National. The 200-4R was configured with several different torque converters and gear ratios depending on the vehicle application.

Unlike the 700R4, most 200-4Rs have a multicase bellhousing for use with Chevrolet, Buick/Olds/Pontiac (BOP), and Cadillac engines. However, 200-4Rs share mounting locations with the TH-400. Since the external dimensions are similar to the TH-350 (overall length, drive shaft yoke spline count/diameter and general size), 200-4Rs are often swapped in place of TH-350s in older vehicles to provide an overdrive gear.

Early models had PRND321 on the cluster, while later models had PRN(D)D21, with the left D identified as the overdrive gear by a square or oval ring.

The THM200-4R can be found in the following vehicles:

1981-90 B-Bodies
1981-84 C-Bodies
1984-88 G-Bodies
1985-90 D-Bodies
1981 Pontiac Firebird (with 301cid engine, non-turbo)
1989 Pontiac Firebird Trans Am Indy Pace car (with Buick V6 and a Turbocharger)
The THM200-4R was phased out after 1990; its final usage was in the GM B-body vehicles.

The gearing for the 200-4R is:

First - 2.7405404:1
Second - 1.567567:1
Third - 1.00:1
Fourth - 0.673913:1
Reverse - 2.07:1


THM700R4 / 4L60 / 4L60E / 4L65E / 4L70E[edit]
See also: GM 4L60-E transmission
The four-speed Turbo Hydra-Matic 700R4 was introduced for the 1982 model year for use in Chevrolet/GMC vehicles.

In 1990, the Turbo Hydra-Matic 700R4 was renamed the 4L60. Under the new designation, the "4" stands for the number of forward gears, the "L" for longitudinal applications (rear-wheel-drive), and the "60" is the strength rating (less than the 4L80). "60" is the relative torque value. For example, 80 is stronger than 60, which is stronger than 40, etc. A 4L80-E can handle more torque than a 4L60-E. The "E" denotes electronically controlled shifting. The 4L60 however is hydraulically shifted based on governor pressure and throttle valve (TV) cable position. 1992 was the last year of widespread usage of the 700R4 (4L60). The 1993 Camaro, Corvette and Typhoon were equipped with the last production 700R4. The last design change of the 700R4 was an added checkball to the valve body.

In 1992 electronic controls were added, and it became the 4L60-E. The 4L60E is not easily swapped with the 4L60, as the 4L60E depends on an ECU to shift.[2] The 4L60E went into service in trucks, vans, and SUVs in 1993 and in all RWD passenger cars (Corvette, F and B/D bodies) in 1994.

In 2001, an updated version — the 4L65-E, was introduced. Five-pinion planetaries, along with a strength-improved output shaft, were improved to withstand the 300+ lb·ft (400+ N·m) of torque of the 6.0 Vortec engine. The 4L70E transmission is the same as a 4L65E with a speed sensor located in the pump.

700R4 / 4L60 / 4L60E / 4L65E / 4L70E / Technical Description[edit]
The Turbo Hydra-Matic 700R4 can be identified by an oil pan number six shown at General Motors Transmission Pans.

The tailshaft housing is held onto the main case by four bolts (the bolt spacing is similar to the THM350), and uses a square-cut o-ring seal, and not a gasket. The typical width of this transmission where it bolts to the engine is 20 in (51 cm) overall. From the engine/trans mating surface to the cross member mount bolt is 22.5 in (57 cm), and engine/trans surface to output shaft housing mating surface is 23.375 in (59.37 cm) overall, with the tail shaft housing typically measuring 7.625 in (193.7 mm). External dimensions are similar to a THM350 with a 9 inch tailhousing found in Chevrolet/GMC long wheelbase truck/vans and 1971-76 B-bodies (Bel Air, Impala, Caprice).

Transmission fluid cooler lines on the 700R4 the bottom fitting on the right side of the transmission is the "out" line to the cooler and the top fitting is for the return line from the cooler. These fittings are .25 in (6.4 mm) pipe thread, and can include an adapter from the factory for threaded steel lines in a SAE size. 4L60Es manufactured after 1995 use snap-in connections instead of threaded.

The original version of the transmission had a 27-spline input shaft (shared with the THM200C and 2004R) which was a common failure point. In 1984, the 700R4 designed for use behind Chevrolet small block V8s received a 30-spline input shaft similar to those found on TH400 transmissions and which also used a different torque converter than its 2.8 V6 and 2.2 L4 engines. Between 1984-1987, internal components, from the ring gear to the oil pump housing, were updated, ending with the auxiliary valve body for 700s manufactured after October 1986.

In 1995, the 4L60E received a PWM-controlled lockup converter. The early designs simple on or off lockup function while the later design can variably lock as to not feel the lock up occur. GM added a 5th solenoid to the valve body, called the PWM solenoid.

In 1996, GM introduced a redesigned 4L60E transmission case that incorporated a bolt-on bell (2 piece case, bell and case) housing and an 6 bolt tail housing. This 2 piece case style was first seen in 1996 and up model S-10 Blazer, S-10 Truck, GMC Jimmy, and GMC Sonoma with the 4.3L engine. In the large majority of 1998 & later applications of the 4L60E were 2 piece cases (i.e., a removable bell housing). Both transmissions are the same internally. The non-PWM (1993-1994) style 4L60Es are not interchangeable with PWM-style (1995 and later) 4L60Es. Also in 1996, GM changed the 3-2 solenoid to a different style which makes it not interchangeable with any previous models.

For the model year 1996 GM trucks, there were 2 versions of the 4L60E transmissions. One had a bolt on bell housing the other did not. The bolt on bellhousings used on the 4.3L and 1996-2002 GEN I+ versions of the Small Block Chevrolet used the same bellhousing while the LSx engines used a longer bellhousing to accommodate a redesigned torque converter with a longer pilot nose (GM sells an adapter assembly for using the LSx 4L60-Es when used with an early engine).

The gearing for the 700 is:

First - 3.06:1
Second - 1.63:1
Third - 1.000:1
Fourth - 0.70:1
Reverse - 2.29:1
(Gear ratios are always expressed to x.xx rounding +/- as a worldwide industry standard, actual mathematical ratios may vary)

700R4 / 4L60 / 4L60E / 4L65E /4L70E Applications[edit]
[3][4]

1982-1992 Chevrolet Blazer/GMC Jimmy
1982-2005 Chevrolet Corvette
1983-1996 Chevrolet Impala and Caprice police specials equipped with 350 engines.
1983-1985 Oldsmobile 350 Diesel equipped models.
1983-2002 Chevrolet Camaro/Pontiac Firebird
1985-2005 Chevrolet Astro/GMC Safari
1991-1992 GMC Syclone
1991-1992 Oldsmobile Custom Cruiser
1989-2003 Chevrolet S-10/GMC S-15/Sonoma
1989-2005 Chevrolet S-10 Blazer
1989-2001 GMC S-15 Jimmy
1990-1996 RWD Cadillac Fleetwood/Cadillac Brougham/Cadillac Limo
2002-2009 Chevrolet TrailBlazer/GMC Envoy
1992-1993 GMC Typhoon
1984-2010 Chevrolet Suburban
1982-2012 Chevrolet Van
1994-1996 Chevrolet Impala
1994-1996 Buick Roadmaster
1993-2010 Chevrolet C/K
1993-2010 Chevrolet Tahoe/GMC Yukon
1999-2006 Cadillac Escalade
2002-2008 Chevrolet Avalanche
2003-2007 Hummer H2
2004-2007 Buick Rainier
2004-2012 Chevrolet Colorado/GMC Canyon
1988-2006 Holden Commodore
2004-2006 Pontiac GTO
2005-2009 Saab 9-7X


edit: See what you started, Mark!?!?!

PS: still haven't been able to get to my swap yet...

HA ! Good review. Sometimes its good to get things out for discussion.

A few notes to add; while its true that the 4L60E usually requires a electronic controller there is a way to control the line pressure using a vacuum modulator (like a TH350) and a push button module to shift the gears (mind you its a full manual operation) - push button 1 - you get 1st gear, push button 2 - you get 2nd gear, push button 3 - you get 3rd gear, push button 4 - you get OD. A vacuum switch like used on the 700r4 can be used to lock up the converter. The PWM signal for lock is part of the push button box.

Alternatively PCS makes an excellent controller that uses 4 knobs on the front panel to set up the shift points, lockup and shift firmness. Its well suited for folks that don't like computers - its simple to use and install. The upside no throttle cable/brackets to deal with like on a 700r4.

Some time next year I plan on putting a 4l60 into my 2nd gen (1979), so I'll know all the gritty details once done.

95% of the late model stronger 4l65/70e factory parts swap back to the earlier 700r4 (30 spine input shaft).

This is a problem I need to worry about? Yikes.

Ok, after months of no work, got some time to work on the car.

1) All oil pan bolts are now properly torqued. You can read in a different thread how the engine builder didn't tighten them.

2) Backed the PV to 9.5. My last experiment was 10.5. Other settings: main jet 54, accelerator 35, secondary 59, timing 8BTDC with max at 40BTDC. My notes said 8.5PV had a lot of hesitation, so I don't want to drop back to that.

3) Disconnected water from manifold. My epoxy seals for the Offenhauser intake were leaking water (yeah, should've welded aluminum over them). Car seemed to run fine today, so maybe I'll just leave it as is. I don't run during freezing. I'm using stubbed hoses now, I'll need to cap them if I do.

Next thing to do is to replace one of my transmission cooler lines. I just couldn't get the joint to seal. I had the joint in a bad place, under the engine mount. This winter I removed the joint to get to it, but it's still drip, drip, dripping. So a new line is on order. After this, it's all pretty much done until it's time to put a 3.55:1 rear end in it (3.08 today). Time to get the interior work don.

The car had a great run last weekend, weather was beautiful 60F hazy skies. So we drove up into the foothills, got some ice cream and played a game of chess. :-)

The new transmission hose appears to have done the trick. It looks like the previous tube had gone too far into the hose joint. The compression fitting had the line compressed, looked like the fitting couldn't get far enough in. It's hard to get it just right, but it looks like it's okay.

I ran a single solid line from my trans cooler to the trans on the 2004r. You'll have lots of bends so movement shouldn't be an issue. It was straight forward enough. Just took a bit of routing and time.

Now that I've been driving the engine and have the carb tuned, I'm not satisfied with what I've done. I could use a taller gear in the rear, but even with a 2200-2400 RPM stall converter, it won't overcome the low-end just drag. I put in too big of a CAM. Yeah, some will say I told ya' so, so I'm saying it for you. I have an opportunity with my leaking oil pan gasket to fix that with only the CAM cover gasket as gbauer suggests. Maybe I do a CAM swap at the same time. More work, yes, but the car will feel better.

To remind you of the specs...
- 200-4R 4-speed, 3.08:1 rear end
- Langdon iron headers, Holley 390
- 250 (conversion from 230)
- hardended exhaust seats, 1.5" stock size
- enlargened intake valves, 1.72" to 1.84"
- flat top pistons to increase compression
- 0.040" overbore
- COMP Cam 280H,
Intake & exhaust: duration: 280, duration @ .050": 230, valve Lift 0.536, lobe lift 0.306
RPM Range: 1500-5500
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=62&sb=2

I like goosing the engine, going from 1st to second the tires chirp pretty good. But getting started, even from 2200 RPM, it's super sluggish. I should've known, it needs an even bigger stall which turns out just won't work so well with how I usually drive it.

Now, the question is which CAM to go with?

Stock: (I just have a hard time going stock). But what about the torque and such?
Intake: duration: 240, duration @ .050": 192, valve Lift 0.455, lobe lift 0.26
Exhaust: duration: 248, duration @ .050": 200, valve Lift 0.455, lobe lift 0.26
RPM Range: 500-4500
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=58&sb=2

One step up, the 252H:
Intake & exhaust: duration: 252, duration @ .050": 206, valve Lift 0.474, lobe lift 0.272
RPM Range: 800-4800
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=59&sb=2


Another step up, the 260H:
Intake & exhaust: duration: 260, duration @ .050": 212, valve Lift 0.489, lobe lift 0.28
RPM Range: 1000-5000
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=60&sb=2

It seems like the 252H is the way to go, but what do I really know? I'd like to see torque improvements in the 2K-3K range.

From earlier thread...

Comparison to my stock 230

stock 230 => Torque 220 at 1600 HP 140@4400
stock 250 => Torque 235 (+7%) at 1600 HP 155@4200 (+11%)
big cam 250 => Torque 205 (-7%) at 2000 HP 246@5300 (+76%)

My big cam on the gonkulator
Torq 205 at 2000 (less than a bone stock 250!)
Torq 268 at 3800 (now it wakes up)
Powr 246 at 5300

Gonkulator Stock 250 (no other changes from above 15.82 at 85.2):
Torq 229 at 2600
Powr 154 at 3800

I am always conservative on cams.
Here is something you can try that is way easier and could solve your problem. Install some bleed down lifters. Rhoads is a popular lifter and they kinda pioneered the idea of a variable rate lifter.
You can use lifters made for SBC and they will not take long to install.
You will gain idle vacuum and torq at low rpm. Your cam should make nice power from 2500 even as it is.
I have my Thrifty Cam in the wagon's 250. It pulls like a mule from a dead stop.

Try the lifters, they are easy to do.

Oh my goodness, I had it wrong. I've got the 260H installed, not the 280H, this isn't as bad as I'd thought. Tom, I now remember talking with you and I thought going much higher was not what I wanted. I found the order form and confirmed it was the 260H. I had written down my initial thought and didn't delete/update it.

These Rhoads lifters look awesome, they'll take it back close to the stock at low RPMs. It looks like the V-Max Rack are the ones for this engine. You can order a kit for the 6 cyl. The "Super Lube Groove Option" is supposed to get more oil to the CAM. Not that I'm going to change oils, but do you think that would alleviate the need for high-zinc oil?

On the installation, it says you go one by one adding the lifters with the cylinder at TDC, put in a 0.020" feeler gauge, and adjust to the point where they bottom out and start to open the valves. That's it? No adjustments after the fact?

Documentation says they should clatter a bit at lower RPMs.

I think there is something else wrong with your setup if that is the cam you have. You better double check the #'s. I remember a post many moons ago from you saying about using the big 230 duration cam.

If you have a 260 cam, something else is wrong, my engine pulls like a mule even at low rpm with similar cam.
You have even road in mine.

Mark,
Back in Oct of 2016 , you said it had the comp 280 cam with 230 duration. It makes a big difference. Which one do you have?

Hi Tom,

I thought I had the 280H for some reason. But when I looked at the bill from the machine shop, it had "61-233-4" as the part number for the camshaft. This is the 260H, which I'm glad because the 280H is too tall for my use. 260H seems like it's what I should have.

Things to work on: 1) mechanical advance, 2) bump up the timing since it's too low at operating RPMs. I still wonder why that distributor drops timing 1 degree from 700->800 RPM.

I'll try to do a comparison of the springs I have with the ones from the set to see if they compare to heavy or light. After that, it's time to take it to the carb connection to have them rear wheel dyno it, check and adjust the carb according to an O2 sensor.

I'll get to the distributor/timing next weekend. There's football to watch this afternoon!

What else should I be looking at for now?

Mark

Hey folks,

I've been distracted the past year rebuilding my 1980 Chevy k20 4x4. Still another six months before that's done, about two years (or is it three???) in the making. I put a new build SBC into it, just can't wait to get her on the road. You all will be happy that I resisted abandoning the truck project and putting the sbc into the Camaro instead. It looked really nice sitting next to it on the crate. Tempting.

Anyways, the Camaro is a cruiser and not a track star and I still am not satisfied with it. 0-60 is tepid at best due mostly to the low-end performance. Higher rpms sing. Gas mileage is horrendus. It’s spring, time to do some work to get this car running right.

There's a number of things that I did right with the build but more things that I did wrong. I'll put a list here.

Good
1) converted 230 to 250, flat head pistons
2) 200-4r upgrade from the power glide
3) headers and Clifford intake
4) stainless exhaust
5) electronic ignition

Bad
6) too big a CAM for my use compcams 260H p/n 61-233-4 (yeah, you told me so…)
7) widened exhaust valves (yeah, you warned me…)
8) too wide tires on rear for this engine (235/60r15). Well, too wide in general for the car.

Neither good nor bad
9) Holley 4 bbl carb
10) 2200rpm torque converter

Manifestations:
- Slow off the line at lower RPMs, but will chirp the tires shifting 1st to 2nd.
- Requires richer jets, gas mileage is awful (13 or 14, even with OD).
- Timing needs to be very far advanced at low RPMs (i.e. 18 without vacuum at idle) to get any sort of performance out of this.

Dealing with #6 and #7, the timing is very far advanced, but the distributor is not set up properly.

Now, there are things I can do and things I can try and things I can fix…

One Experiment I could run: Put the original points & condenser distributor back in, measure the timing curve and compare to my aftermarket EFI. See how it runs. I think it would be rather interesting to put the original distributor back in and try it out. I think the resistor wire is still there for me to use.

Things I can do:
- Install Rhoads lifters to accommodate the larger CAM and larger exhaust
- Get the distributor adjusted properly for this engine
- Convert to 2 BBL Holley EFI carb
- Smaller tires (225 or 215) on rear
- Put a smaller CAM into it (ugh)

I’d like your thoughts. The biggest issue is the CAM, bigger exhaust valves and loss of low-end torque. That needs to be addressed first.

Thanks,
Mark

I posted in the "what's your timing" thread about today's experiment. The HEI distributor I have is set up with a much flatter curve than the original distributor. The original, with points & condenser, seems to run better.

I knew I needed to set up the distributor, didn't realize it was like this. Instead of setting up the distributor, I'm going to put in a Pertronix. I can go with the lightest weight advance spring and get similar to what I got with the original. I always run premium which says it should be okay.

I don't have a way to post pictures, but can post video of the three charts I built.

https://youtu.be/_qEEwLWeaVc

Danged speedometer broke on my test run, it was so smokin!

Have any of you used Rhoads lifters? What's your experience?

Rhoads lifters are the pump up hydraulic lifters that increase effective lift at higher engine speeds when oil pressure increases. We used a couple of sets of them thirty years ago with mixed results.

The one set SEEMED to perform a little better at higher RPMs, but we never got to run actual tests at the track to confirm those results.

The other try wasn't successful. The engine either wouldn't idle properly with the valve lash set to specs, or it wouldn't rev because we opened up the valve lash to get it to idle.

LOOOONG time ago!! I don't know if the "technology" has improved or if they're even still around.

There were several different leak-down hydraulic tappets, mixed reviews.
1. low oil pressure delays the added duration
2. low oil viscosity delays the added duration
3. low oil temperature speeds up the added duration

These factors work against consistency, stall speed, etc.