New 434 Clevor build

New 434 Clevor build

Joined: November 25th, 2006, 4:54 am

November 11th, 2011, 9:58 pm #1

Hi guys,

Just thought I'd throw up my new build. My 393 Clevo started to die with a cracking block, so I've been putting a new engine together over the year. I've swapped to a Dart block and was simply going to put my 393 gear into it.....but things kinda went out of control

Going to be n/a on E85.

9.2 Dart block with Clevo mains, will be bored to 4.155
4" forged crank
6" Scat rods w/ARP 2000 bolts
Custom Racetec forged pistons 13.5:1 comp
CHI 225 heads
CHI dominator manifold
1050 Pro Systems E85 Dominator
Comp Cams solid roller
Jessel shaft rockers, Ti valves & Manley springs
AMP belt drive

......still need to pick up a few more parts.

Not sure what it's going to make, but it's going in a stick shift 3500lb street strip car which should be fun! It should be making peak power from 7000-7500rpm.

Just a quick question on rod ratios, of which I know there are a lot of theories! I like the one that talks about deciding on a crank and get the piston you need, then the rod connects the two. Just looking at things from a piston/cylinder side load view.....the shortish 9.2 decks tend to force the short rod ratio. I've gone a 6" rod to increase the pin height to 1.2 as I've got some rather large valve reliefs for the big cam. 6.2 rod would have only given a 1" pin height and a 6.125 is a 1.075.

With the 4.155 bore also being larger than the 4.000 stroke (over square I think it's called) and all other things aside, what sort of RPM limit would you put on a 1.5 rod ratio? It's only a short burst drag engine, not endurance. I've seen other 1.5 rr engines in 24hr endurance circuit racing cars pulling 6500 all day.....and my cam won't be going over 7500 anyway, so just food for thought.

I'll keep you updated on the build!

Cheers

Quote
Like
Share

Joined: November 18th, 2002, 1:16 pm

November 11th, 2011, 11:35 pm #2

Since I know pretty much your entire build, I can safely say you are in no need of worries on rod stroke ratio. As far as a 1.5 ratio, we have made over 2350 hp at 9000 rpm with 36 psi of boost on gas. One consideration at too often gets over looked on the subject is actual rod angularity and not just the ratio of the two. Just taking the ratio of the two ASSUMES that the pin, piston, cylinder, and crank are all in a perfect line at TDC and BDC. Rarely is this the case.

Mark McKeown
McKeown Motorsport Engineering, Inc.
http://mmeracing.com
http://racecrateengines.com
Mark McKeown
McKeown Motorsport Engineering Inc
http://www.mmeracing.com
301-246-9225
Quote
Like
Share

Joined: February 13th, 2006, 4:59 am

November 12th, 2011, 2:30 am #3

Hi guys,

Just thought I'd throw up my new build. My 393 Clevo started to die with a cracking block, so I've been putting a new engine together over the year. I've swapped to a Dart block and was simply going to put my 393 gear into it.....but things kinda went out of control

Going to be n/a on E85.

9.2 Dart block with Clevo mains, will be bored to 4.155
4" forged crank
6" Scat rods w/ARP 2000 bolts
Custom Racetec forged pistons 13.5:1 comp
CHI 225 heads
CHI dominator manifold
1050 Pro Systems E85 Dominator
Comp Cams solid roller
Jessel shaft rockers, Ti valves & Manley springs
AMP belt drive

......still need to pick up a few more parts.

Not sure what it's going to make, but it's going in a stick shift 3500lb street strip car which should be fun! It should be making peak power from 7000-7500rpm.

Just a quick question on rod ratios, of which I know there are a lot of theories! I like the one that talks about deciding on a crank and get the piston you need, then the rod connects the two. Just looking at things from a piston/cylinder side load view.....the shortish 9.2 decks tend to force the short rod ratio. I've gone a 6" rod to increase the pin height to 1.2 as I've got some rather large valve reliefs for the big cam. 6.2 rod would have only given a 1" pin height and a 6.125 is a 1.075.

With the 4.155 bore also being larger than the 4.000 stroke (over square I think it's called) and all other things aside, what sort of RPM limit would you put on a 1.5 rod ratio? It's only a short burst drag engine, not endurance. I've seen other 1.5 rr engines in 24hr endurance circuit racing cars pulling 6500 all day.....and my cam won't be going over 7500 anyway, so just food for thought.

I'll keep you updated on the build!

Cheers
That engine sounds like it should run hard!what are your cam specs? Similar build to mine only I used a little longer rod. Good luck. Oh ya aren't those racetec pistons a work of art ?
Quote
Like
Share

Joined: February 17th, 2004, 11:02 pm

November 12th, 2011, 2:54 am #4

Hi guys,

Just thought I'd throw up my new build. My 393 Clevo started to die with a cracking block, so I've been putting a new engine together over the year. I've swapped to a Dart block and was simply going to put my 393 gear into it.....but things kinda went out of control

Going to be n/a on E85.

9.2 Dart block with Clevo mains, will be bored to 4.155
4" forged crank
6" Scat rods w/ARP 2000 bolts
Custom Racetec forged pistons 13.5:1 comp
CHI 225 heads
CHI dominator manifold
1050 Pro Systems E85 Dominator
Comp Cams solid roller
Jessel shaft rockers, Ti valves & Manley springs
AMP belt drive

......still need to pick up a few more parts.

Not sure what it's going to make, but it's going in a stick shift 3500lb street strip car which should be fun! It should be making peak power from 7000-7500rpm.

Just a quick question on rod ratios, of which I know there are a lot of theories! I like the one that talks about deciding on a crank and get the piston you need, then the rod connects the two. Just looking at things from a piston/cylinder side load view.....the shortish 9.2 decks tend to force the short rod ratio. I've gone a 6" rod to increase the pin height to 1.2 as I've got some rather large valve reliefs for the big cam. 6.2 rod would have only given a 1" pin height and a 6.125 is a 1.075.

With the 4.155 bore also being larger than the 4.000 stroke (over square I think it's called) and all other things aside, what sort of RPM limit would you put on a 1.5 rod ratio? It's only a short burst drag engine, not endurance. I've seen other 1.5 rr engines in 24hr endurance circuit racing cars pulling 6500 all day.....and my cam won't be going over 7500 anyway, so just food for thought.

I'll keep you updated on the build!

Cheers
> Just a quick question on rod ratios, of which I know there are a lot of theories!

Kaase told me his rule of thumb is rod length should be 2" (or more) longer than stroke.  He said that has worked well for him on everything from 289's to IHRA mountain motors.   That works for your 4" stroke and 6 rods.

Dan Jones
Quote
Like
Share

Joined: November 25th, 2006, 4:54 am

November 12th, 2011, 9:02 am #5

Since I know pretty much your entire build, I can safely say you are in no need of worries on rod stroke ratio. As far as a 1.5 ratio, we have made over 2350 hp at 9000 rpm with 36 psi of boost on gas. One consideration at too often gets over looked on the subject is actual rod angularity and not just the ratio of the two. Just taking the ratio of the two ASSUMES that the pin, piston, cylinder, and crank are all in a perfect line at TDC and BDC. Rarely is this the case.

Mark McKeown
McKeown Motorsport Engineering, Inc.
http://mmeracing.com
http://racecrateengines.com
Thanks for the info Mark. Well 9000rpm puts an end to that issue.....wont't be going anywhere near that! Had just been reading up on a few "performance" websites that can put out a lot of incorrect information.

The heads and manifold look mighty fine! Should comfortably lift the front wheels in the air!

Just for the others reading the above engine combo.....Mark from MME has waved his magic wand on my heads and manifold and also supplied the stroker kit. The domi manifold feels quite a few pounds lighter than my old 4150.

Thanks for helping plan out my initial combo and sharing your wealth of information.

Is simply torquing up the rocker stand bolts sufficient to keep them aligned with the valve tip? Jesel say you can weld the stands together once set (but some are out alone) or I've seen some use roll pins thru the stands?
Quote
Like
Share

Joined: November 25th, 2006, 4:54 am

November 12th, 2011, 9:07 am #6

That engine sounds like it should run hard!what are your cam specs? Similar build to mine only I used a little longer rod. Good luck. Oh ya aren't those racetec pistons a work of art ?
Will be up around the 280/290ish @ 50 with mid 700's lift.

The pistons look great. I'll throw up a few pics later.....went in and picked them up and got the bonus free t-shirt!
Quote
Like
Share

Joined: February 13th, 2006, 4:59 am

November 12th, 2011, 3:26 pm #7

Thats pretty healthy duration at .050.Is this going in light vehicle?I was running 262-270@.050 ,728 lift Oh just had a look 3500 lbs.What do you think your launch will be around 5500?
Last edited by steve.k on November 12th, 2011, 3:29 pm, edited 1 time in total.
Quote
Like
Share

Joined: February 18th, 2005, 2:39 am

November 12th, 2011, 4:44 pm #8

Hi guys,

Just thought I'd throw up my new build. My 393 Clevo started to die with a cracking block, so I've been putting a new engine together over the year. I've swapped to a Dart block and was simply going to put my 393 gear into it.....but things kinda went out of control

Going to be n/a on E85.

9.2 Dart block with Clevo mains, will be bored to 4.155
4" forged crank
6" Scat rods w/ARP 2000 bolts
Custom Racetec forged pistons 13.5:1 comp
CHI 225 heads
CHI dominator manifold
1050 Pro Systems E85 Dominator
Comp Cams solid roller
Jessel shaft rockers, Ti valves & Manley springs
AMP belt drive

......still need to pick up a few more parts.

Not sure what it's going to make, but it's going in a stick shift 3500lb street strip car which should be fun! It should be making peak power from 7000-7500rpm.

Just a quick question on rod ratios, of which I know there are a lot of theories! I like the one that talks about deciding on a crank and get the piston you need, then the rod connects the two. Just looking at things from a piston/cylinder side load view.....the shortish 9.2 decks tend to force the short rod ratio. I've gone a 6" rod to increase the pin height to 1.2 as I've got some rather large valve reliefs for the big cam. 6.2 rod would have only given a 1" pin height and a 6.125 is a 1.075.

With the 4.155 bore also being larger than the 4.000 stroke (over square I think it's called) and all other things aside, what sort of RPM limit would you put on a 1.5 rod ratio? It's only a short burst drag engine, not endurance. I've seen other 1.5 rr engines in 24hr endurance circuit racing cars pulling 6500 all day.....and my cam won't be going over 7500 anyway, so just food for thought.

I'll keep you updated on the build!

Cheers
Glad to hear someone else is building a Clevor with the new CHI 225 heads. I won't be going too radical with mine because it is only going to be used on the street. Perhaps some road racing, but nothing agressive.

Fontana Block bored to 4.125
Lunati Forged Crank 3.75 stroke 401 cubic inches
Carrillo 6" Rods
CHI 3V 225cc heads
CHI 3V 4150 Intake manifold
Titan Oil Pump
Aluminum Steffs 10 quart road racing oil pan
Aluminum flywheel and twin disc clutch
Solid Flat Tappet Cam. (specs still to be determined 6500 rpm redline)
F.A.S.T XFI 2.0 sequential port fuel injection
Ram air system via side scoops and sealed air box

Estimated weight of car will be between 2900 and 3000 pounds. I know a lot of people are into using roller cams these days, but we felt that the old school flat tappet cam was the way to go on this build. Will be running zinc additive in the oil all the time. I also don't mind adjusting the valves once in a while. Although I am old, I'am still thin and flexable enough to climb into the engine bay of a Pantera and work on it.
Quote
Like
Share

Joined: February 13th, 2006, 4:59 am

November 12th, 2011, 5:17 pm #9

Looks like all good parts for sure!I see you have Fontana block are they still around or what?
Quote
Like
Share

Joined: November 25th, 2006, 4:54 am

November 12th, 2011, 5:35 pm #10

Thats pretty healthy duration at .050.Is this going in light vehicle?I was running 262-270@.050 ,728 lift Oh just had a look 3500 lbs.What do you think your launch will be around 5500?
Yeah, I think I should be able to shave a few hundred pounds out of the car, but that seems to keep getting offset with strengthening the chassis and putting a cage in etc.

It's a little bit heavy, but this new engine should have a bucket of torque, still trying to figure out a rear gear for it.....but I think I'll choose that once the engine comes off the dyno, which will give me an idea of mph. Will be running a 28" tyre, maybe 4.11-4.56 rear.......and 4 stick gears to slam thru & alloy flywheel, so there won't be anthing holding it back!

I'd probably say 5500 would be somewhere around an OK starting launch rpm. I'll be hooking up one of those McLeod hydraulic or Bianti magnetic clutch release options to launch off the line which will be fun. Just need to get my McLeod soft-loc clutch reset for the extra torque.......with the help of a driveline data logger.

My last solid flat tappet 393 had the comp cams 295B-6 specialty cam. That had 260/270@50 but was lower on the lift at 638/645. Made peak power at 6950.
Quote
Like
Share