#101  
Old 05-15-2022, 07:12 AM
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Dennis. Congrats on getting the car out. You and your brother really do some top notch work, and it shows. The car is beautiful and those are great et's for what all your working with. I think now its time for you to and Dan to go head to head. Tempest vs lemans 455ho post coupe war! Have a good one.

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1970 Formula 400 4 speed
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  #102  
Old 05-15-2022, 11:55 AM
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Mike Kasparian,Sr. Mike Kasparian,Sr. is offline
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Dennis , beautiful car and great performance . Love the color and being a post car what's not to like . What compression and casting number heads were on the 70 400 T37 ? Number 12 being the ram 3 head . Thanks Mike K

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  #103  
Old 05-15-2022, 03:21 PM
SD455DJ SD455DJ is online now
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Wow, that is a light race weight for a '70. My '65 had a race weight of 3758 lb with a TH400.
I was expecting about 3650 lbs. with a half tank of fuel with the spare tire in place. My brother Dan's '71 T-37 455HO weighs 3675 in the same configuration...TH400, 3.55 12-bolt rear, dual exhaust, no PS/PB, taxi cab interior...a stripper. It is what it is...

Dennis

  #104  
Old 05-15-2022, 03:23 PM
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Dennis. Congrats on getting the car out. You and your brother really do some top notch work, and it shows. The car is beautiful and those are great et's for what all your working with. I think now its time for you to and Dan to go head to head. Tempest vs lemans 455ho post coupe war! Have a good one.
Thanks Matt! His 455HO has me covered by a solid half second though in his T-37 (12.52 @ 107 mph).

Dennis

  #105  
Old 05-15-2022, 03:29 PM
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Originally Posted by Mike Kasparian,Sr. View Post
Dennis , beautiful car and great performance . Love the color and being a post car what's not to like . What compression and casting number heads were on the 70 400 T37 ? Number 12 being the ram 3 head . Thanks Mike K
Thanks Mike! The 400 is the small valve XV code 400 that had the 10.0 to 1 (80 cc) small valve #16 heads. It was rated 330 hp/430 lb-ft torque and available in the non-GTO A-bodies and Catalina/Executive B-body models. With a minimal cut to ensure they were flat, the measured 78 cc's, otherwise totally stock (190 cfm intake/145 cfm exhaust flow). The calculated static compression ratio is 9.94 to 1. Have to run true log exhaust manifolds, not RA's.

Dennis
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  #106  
Old 05-19-2022, 01:04 AM
will slow gto will slow gto is offline
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Dan and I finally had the opportunity to run the ’70 Tempest with the XV code 400 (330 hp/430 lb-ft torque) at the May 12 & 13th F.A.S.T. race at Martin US-131 Raceway Park. This is the first time it’s been out in public since I got the car 4 years ago (already!), also the first time on the dragstrip, so, we were pretty excited and nervous how it would perform. The engine was dyno’d over 2 ½ years ago, so, after a quick once over of the fluid levels, bolts, lugnuts, brakes, fuel lines, hose clamps, double checking the timing (36 degrees all in by 3200 rpm), and pumping up the G70’s to 40 lbs. all around, we were ready to race. Oh, we added 6 gal. of 110 leaded race gas ($72!!!) to the 14 gal. of Shell 93 E10 ($5.10/gal.) just to guard against any potential detonation as it was 88 degrees both days! We left the carb jetting alone from the dyno session (73 jets/43 rods primaries & CG (.0774M tip) secondary rods on a ‘K’ hanger) and never touched again over the next 2 days (plugs read great each day). The 3.42 gears are definitely not ideal for racing (went through the traps at around 4900 rpm), but it is a street car, not purpose built and/or optimized for the pure stock drags…however, 3.73’s or 3.90’s would be much better suited for the track.

The three best passes were 13.1843 @ 103.88 mph, 13.2045 @ 103.09 mph, and 13.2182 @ 102.90 mph in the oppressive heat with OK 1.92 – 1.97 sec. 60’ times. The worst times were in the 13.40’s when the line was slick and spun hard. It was fairly low humidity on Thursday, but shot up on Friday. I heard that the DA’s were 2200’ on Thursday afternoon and over 3500’ on Friday afternoon (unsubstantiated – maybe someone could verify?). Regardless, we are very happy with the cars performance, right where we were hoping it to run.

Another surprise was the weight…3815 lbs. with me in it…way heavier than I was expecting…by 150 lbs.! So the AMA weights are real close for this car as optioned (3643 lbs. + 165 lbs. (me) = 3808 lbs.) with a full tank of gas, no spare tire though (in the trunk that is…not my waist). It’s still 300 lbs. lighter than my ’70 RAIV/TH400 Judge (OPH – Roger – you were right on with the weight!).

We’re quite confident with some further sorting out of the suspension (pretty stiff and little to no front end lift) and cooler weather, it could run high 12’s. The lower mph is indicative of the small valves (lower air flow) of the heads, the log exhaust manifolds with the 2.1” outlets, and fighting the 3.42 gears. But, it was a blast getting back on the track as it’s been since 2007 (15 years) the last time I raced in the pure stocks (or anything for that matter!).

Dennis
Wow, 13.2 @ 103 is really moving for a car with logs, 3.42s and a 2800 cam. You guys sure know how to squeeze every last drop of performance out of these stockers. Bravo!

  #107  
Old 05-19-2022, 07:32 AM
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Wow, 13.2 @ 103 is really moving for a car with logs, 3.42s and a 2800 cam. You guys sure know how to squeeze every last drop of performance out of these stockers. Bravo!
Thanks W.S.GTO! If we built the 400 to the max the pure stock rules allow, I could run as much as 11.5 to 1 compression (1.5 over advertised 10.0), and any hft cam (actually have a 2801 in it now) that maintains 16 in. vacuum at 1200 rpm (changing to 18 in. this year). Higher compression would allow a bigger cam to maintain 18 in. vacuum, so possibly the 2802 could work, but I think the small valves and log manifolds would be corks (with the 2802 cam) above 4000 rpm and counter productive...not to mention the tradeoff of less torque for higher horsepower wouldn't allow better et's in this particular engine (would work well in a RAIII with bigger valves and RA exh. manifolds!). A 3.73 or 3.90 gear would be more ideal too. With some front suspension work along with all the above, it could run 12.70's at 108 mph. If it weighed closer to 3650 lbs, there's a another .15 seconds lower et!

Dennis

  #108  
Old 11-04-2022, 12:25 PM
KSZR KSZR is offline
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Thanks W.S.GTO! If we built the 400 to the max the pure stock rules allow, I could run as much as 11.5 to 1 compression (1.5 over advertised 10.0), and any hft cam (actually have a 2801 in it now) that maintains 16 in. vacuum at 1200 rpm (changing to 18 in. this year). Higher compression would allow a bigger cam to maintain 18 in. vacuum, so possibly the 2802 could work, but I think the small valves and log manifolds would be corks (with the 2802 cam) above 4000 rpm and counter productive...not to mention the tradeoff of less torque for higher horsepower wouldn't allow better et's in this particular engine (would work well in a RAIII with bigger valves and RA exh. manifolds!). A 3.73 or 3.90 gear would be more ideal too. With some front suspension work along with all the above, it could run 12.70's at 108 mph. If it weighed closer to 3650 lbs, there's a another .15 seconds lower et!

Dennis
Dennis,

My 72 Lemans with 400 .030 over, 068 cam, cast iron intake, log manifolds, HO racing carb and distributor kits, dual snorkel, crush bent quiet exhaust, 3.55 12 bolt, 200 4R does a best 1/4 mile on my dragy of 14.59 at 95.

Going to upgrade to a 2.5" Pypes mandrel system, which sounds like a huge improvement.

What would I gain by going to ram air manifolds over logs? Wondering if its worth it.

Kent

  #109  
Old 11-05-2022, 09:25 PM
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Dennis,

My 72 Lemans with 400 .030 over, 068 cam, cast iron intake, log manifolds, HO racing carb and distributor kits, dual snorkel, crush bent quiet exhaust, 3.55 12 bolt, 200 4R does a best 1/4 mile on my dragy of 14.59 at 95.

Going to upgrade to a 2.5" Pypes mandrel system, which sounds like a huge improvement.

What would I gain by going to ram air manifolds over logs? Wondering if its worth it.

Kent
Kent, Certainly RA manifolds will help with a 3-8 hp & lb-ft of torque gain through the rev range of 2000 rpm and above, especially the larger outlet repops (RARE's 2.45" ID outlets). All exhaust manifolds benefit from 2 1/2" mandrel bent headpipes (Pypes makes them for logs and RA's) to make the most power gain along with mandrel bent pipes to complete the exhaust system. Going to RA manifolds (either stock 2.1" or the 2.45" oversized) will accommodate more power gains in the future should you decide to upgrade your engine, so, IMHO, it's never a bad idea if you can afford it...but, the 68-72 std. A-body log manifolds hold their own on relatively stock builds. I'd be more tempted to open up the outlets to 2.2" on your logs (stock outlets are 1.875" and 1.95)" and save your money if you don't have future plans to make more power with your 400 (B-Man has an excellent thread on opening up his log manifolds and making his own 2.5" mandrel bend headpipes). I think logs are fine up to 350 hp, however, the law of diminishing returns kicks in fast at 350 hp. I know my XV 400 engine that made 380+ hp would have made 400 hp on the dyno with RARE 2.5" manifolds. I didn't open up the outlets on the log manifolds since I race it at the Pure Stock Drags and have to be legal.

Your 400 will be quicker by 0.1 to 0.2 seconds (I think Ccass mentioned this earlier in this thread) quicker with just the manifold change and you'll get another .0.2 to 0.3 second drop with the full mandrel bent Pypes exhaust system.

Dennis

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  #110  
Old 11-06-2022, 01:12 PM
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Kent, Certainly RA manifolds will help with a 3-8 hp & lb-ft of torque gain through the rev range of 2000 rpm and above, especially the larger outlet repops (RARE's 2.45" ID outlets). All exhaust manifolds benefit from 2 1/2" mandrel bent headpipes (Pypes makes them for logs and RA's) to make the most power gain along with mandrel bent pipes to complete the exhaust system. Going to RA manifolds (either stock 2.1" or the 2.45" oversized) will accommodate more power gains in the future should you decide to upgrade your engine, so, IMHO, it's never a bad idea if you can afford it...but, the 68-72 std. A-body log manifolds hold their own on relatively stock builds. I'd be more tempted to open up the outlets to 2.2" on your logs (stock outlets are 1.875" and 1.95)" and save your money if you don't have future plans to make more power with your 400 (B-Man has an excellent thread on opening up his log manifolds and making his own 2.5" mandrel bend headpipes). I think logs are fine up to 350 hp, however, the law of diminishing returns kicks in fast at 350 hp. I know my XV 400 engine that made 380+ hp would have made 400 hp on the dyno with RARE 2.5" manifolds. I didn't open up the outlets on the log manifolds since I race it at the Pure Stock Drags and have to be legal.

Your 400 will be quicker by 0.1 to 0.2 seconds (I think Ccass mentioned this earlier in this thread) quicker with just the manifold change and you'll get another .0.2 to 0.3 second drop with the full mandrel bent Pypes exhaust system.

Dennis
Thanks! I'll go for the RA manifolds and 2.5 X Pypes system.

My goal is to be faster than my wife's Mach E in the 1/4(13.8)! Fun!

What is the next step without just going to a stroker? From reading posts maybe 2801 or 2802 cam? Worth it over the 068?

3.73s might be nice over the 3.55s since I have overdrive.. But the 200 4R does have a much lower 1st gear than a T350 or T400.

Kent

  #111  
Old 11-06-2022, 07:41 PM
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Kent, Might as well ante-up for the 2.5" outlet RA manifolds since you are going that route along with the Pypes mandrel 'X' system. Can't go wrong there and it will support more power down the road (up to 500 hp easily). I personally would get the kit without the mufflers and purchase the 18" case DynoMax UltraFlo's or Magnaflow's separately, which are both straight-thru design, yet fairly quiet, but support lots of power. I have both and they both perform very well.

I see you have #16 heads and I'm assuming the '68 large valve variety. I would certainly follow the same recipe we did on the XV 400 engine on yours. With the large valve heads with .040" quench, lower 10's for static compression, the 2802 cam, etc., I would expect an easy 420 hp/480 lb-ft torque. With your new exhaust system and a fuel delivery system to match, you should have no problems running high 12's at 106+ mph. I'd stick with the 3.55's for a while since your first gear multiplication ratio is 9.7625 with the 200R4's 2.75 first gear...that's like having 3.90 gears with a TH400/TH350! You will have a major traction problem with this build...and lots of fun!

Dennis
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  #112  
Old 11-06-2022, 07:49 PM
KSZR KSZR is offline
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Originally Posted by SD455DJ View Post
Kent, Might as well ante-up for the 2.5" outlet RA manifolds since you are going that route along with the Pypes mandrel 'X' system. Can't go wrong there and it will support more power down the road (up to 500 hp easily). I personally would get the kit without the mufflers and purchase the 18" case DynoMax UltraFlo's or Magnaflow's separately, which are both straight-thru design, yet fairly quiet, but support lots of power. I have both and they both perform very well.

I see you have #16 heads and I'm assuming the '68 large valve variety. I would certainly follow the same recipe we did on the XV 400 engine on yours. With the large valve heads with .040" quench, lower 10's for static compression, the 2802 cam, etc., I would expect an easy 420 hp/480 lb-ft torque. With your new exhaust system and a fuel delivery system to match, you should have no problems running high 12's at 106+ mph. I'd stick with the 3.55's for a while since your first gear multiplication ratio is 9.7625 with the 200R4's 2.75 first gear...that's like having 3.90 gears with a TH400/TH350! You will have a major traction problem with this build...and lots of fun!

Dennis
Very cool! Thanks for your input. Lots to think about!

Would Rhodes lifters make sense with the 2802? Just thinking about retaining the nice Pontiac low end torque and drivability.

Kent

  #113  
Old 11-06-2022, 07:55 PM
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I don't think you will need Rhoads with the 2802 cam and 10.0 to 1 compression in the 400. So far, we've never had any issues with the lifters that come with the Summit cam kits (supposedly Johnson Hy-Lifts), and I'm not a fan of their 'sound'.

Dennis

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  #114  
Old 11-06-2022, 08:07 PM
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Here is my current exhaust coming off the manifold. Look closely, nice crinkle near the clamp.
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  #115  
Old 11-06-2022, 08:16 PM
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Definitely room for improvement! With your new RA manifolds and 2.5" Pypes 'X' system you'll likely need to richen the carb a bit to compensate for the improved flow. Your times should drop to very low 14's and mph jump to 100+ after this...before the engine rebuild that is.

Dennis

  #116  
Old 11-06-2022, 08:26 PM
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I should probably add the .030 bore and rebuild was done by my local machine shop roughly 25 years ago. I gave him the specs from my HO racing book when he rebuilt it. It has less than 6000 miles on it since(I know should have been driving it and enjoying it more). Used a rebuild kit from Warrior.

Heads were redone with HO's springs if I remember correctly along with hardened seats. Ran them on the original 350 with the HO HC-01 cam for a while until changing to the 400.

Should have kept that cam but sold it along the way.

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  #117  
Old 11-06-2022, 08:27 PM
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Definitely room for improvement! With your new RA manifolds and 2.5" Pypes 'X' system you'll likely need to richen the carb a bit to compensate for the improved flow. Your times should drop to very low 14's and mph jump to 100+ after this...before the engine rebuild that is.

Dennis
OK thanks, I'm not a great carb tuner. But can tell you it seems to run fairly rich with the HO kit.

  #118  
Old 11-07-2022, 09:15 AM
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Definitely room for improvement! With your new RA manifolds and 2.5" Pypes 'X' system you'll likely need to richen the carb a bit to compensate for the improved flow. Your times should drop to very low 14's and mph jump to 100+ after this...before the engine rebuild that is.

Dennis
I was a little slow but I hear your humor here.

  #119  
Old 11-07-2022, 01:41 PM
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gosh - can you post a video of racing the mach E after you are done your upgrades...lol

good luck!

  #120  
Old 11-12-2022, 10:22 AM
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I did get a set of manifolds. Had to settle for 2.25", so sign of 2.5" available anywhere.

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