1050 versus 750 Dominator

Old 10-03-2011, 08:11 PM
  #1  
markdunlap
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default 1050 versus 750 Dominator

I have a combination for bracket racing it is too fast for the 6.40 index I need to run. I have tried various normal ways to slow it down and am not satisfied with the results.

I am thinking of removing my 1050 dominator and replacing it with a 750 dominator to slow it down, but haven't heard much good about the 750. It would just be easier to keep the same style carb than go back to a 4150 carb with a adapter spacer that I don't really have hood room for.

Also I don't want to cause a condition that would be harmful to the engine as far as being too lean.

Anyone been there, done that?
markdunlap is offline  
Old 10-04-2011, 03:25 AM
  #2  
TopspeedLowet
Senior Member
DYNO OPERATOR
 
Join Date: Apr 2008
Posts: 504
Default

If you want to slow a car down easily with out killing the tune up, change the rear gears. going from 4.10 to 3.90 or getting a second set of tires with 6" more roll out if you can fit them will probably get you there if you need to gain a few tenths. adding some weight in the rear bumper area will also slow a car down too.
Gears are cheaper than a carb, changing the carb will likely not change your et as much as you hope.
Bruce
TopspeedLowet is offline  
Old 10-04-2011, 07:16 AM
  #3  
TS1955
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2007
Location: Lost Creek, WV
Posts: 533
Default

I run my car in the IHRA Super Rod class (6.40 index) and I use a pneumatic throttle controller on timer that is in my delay box. Maybe this is something you can use. JMO.

TS1955
TS1955 is offline  
Old 10-04-2011, 07:13 PM
  #4  
markdunlap
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default 1050

I have 4.56 gears. Maybe 4.10 would do it.

I have had a throttle stop and did not like it. The guys gave me shi? about it for bracket racing too.

I have added weight and that makes it hook better and goes faster.

What i am doing now is using my delay box to turn on a relay that brings in a MSD retard of 12-15 degree, just after the shift point till near the end of the run, and then back to full timing. But when the weather gets good, 1100 DA this weekend, it still is too fast.

I don't know if a 750 4500 carb would work either, but I can borrow one. Just want to see if anyone had any success with one.

I have been thinking of contacting Patrick at Pro Systems as he built my 1050 and it is a good one.
markdunlap is offline  
Old 10-05-2011, 06:58 AM
  #5  
coloradoracerguy
Senior Member
SENIOR BUILDER
 
Join Date: Dec 2007
Location: Morrison, Colorado
Posts: 120
Default

Run a restrictor plate. I'm thinking of using one of the EZ Plate systems for super comp next year on my car. Ive heard alot of good things about them.
coloradoracerguy is offline  
Old 10-05-2011, 03:12 PM
  #6  
markdunlap
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default 1050

I talked to a guy selling a EZ plate for dominbator on RJ this summer. After I discussed what I wanted to do, he talked me out of it.

It would be convenient to just pull the restrictor and go back fast.
markdunlap is offline  
Old 10-06-2011, 02:56 PM
  #7  
markdunlap
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default 1050

Well, I have reconsidered the restrictor plate suggestion.

I should have one complete by tomorrow night in time to try Sunday.

I am going to make it 1.750". I have some 1/4" aluminum plate to make it from.

Anybody got a better suggestion on size or different slow down idea?
markdunlap is offline  
Old 10-06-2011, 09:19 PM
  #8  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Mark i made about a doz. restrictor plates on the CNC mill for Jimmy Smiths 7.00 index car, running a 750 holly. His car would run 6.60's. I used 1/32" alum and made them in 1/32" increments, he could slow it down to 7.10's with the plates, but as the temp. changed at nite he would still have to add weight to hit the numbers. He won lot's of money by running the plates and they didn't hurt the 60' times.

JMO

Zip.
zipper06 is offline  
Old 10-09-2011, 05:08 PM
  #9  
markdunlap
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default 1050

I tried my new 1.750" restrictor plate today.

Last week I ran 6.38 break out 3rd round.

This week first 2 passes were 6.53 and 6.52, so it did slow it down, and the 60 fts. were both 1.36.

But after their 1 1/2 hour lunch break, it ran 6.49 breakout.

Bought back and won at 6.52 flat out second round.

Third round lost lane choice and had .496 red light and only 6.55, but 60 ft. was off .02 at 1.38.

I still had my 15 degree retard chip on all thru high gear, so I will turn it off next week and see if it runs faster than 6.40. If so, I will get another smaller restrictor plate made, maybe 1.700?

On another note, I went to watch the NMCA race at Indy Saturday and it was a great door car show. Saw 2 cars run 5.98 and 5.99, both double turbos. Lots of low 6.00-6.20 cars there. Even bumped into(literally) Bob Glidden while he was looking over a FORD Shot Gun Hemi twin turbo Mustang. That thing looked like it had 5/8" pushrods.
markdunlap is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service