Fronzizzle

Finally have my engine and trans bolted in the car. I installed the Dyno Don's headers, everything is nice and tight and I'm a little concerned about the amount of clearance I have on the passenger side between the header and the frame.

I can't even get to it to measure it, but if I had to guess I'd say there is no more than 1/16" of space between them, maybe even less. They are not touching as it sits but once the engine is running, I fear that it's going to be banging pretty hard.

The clearance on the driver side is much greater, probably 1/2" or 3/4".

I was going to try and loosen the motor mount bolts and see if I can get the whole engine to move over a little but not sure that's going to work.

Any thoughts?

Dyno Don

iTrader: (7)

The only time I have run into this is when the mounts are switched front left to right.
They are for sure different. The metal stampings.

Fronzizzle

Oh boy. Is there a way to tell when they are on the car if they are on the wrong side? The mounts, I mean. And I assume that you are talking about the part of the mount that bolts to the block and not the part that bolts to the frame, correct?

Fronzizzle

Yep - I had the metal brackets on the wrong side. Switched them today, passenger side clearance went up to almost 1/2" and driver side stayed almost the exact same...I assume this is because the motor is now sitting at a different angle. Anyway, thanks for the advice.

Dyno Don

iTrader: (7)

Glad that fixed it

John in RI

iTrader: (167)

Yes. I've had clearance problems with Dyno Don's Headers. The drivers side header hit the K frame on me,.... Twice. 2 Different cars; each using a different sets of Dyno Dons' Headers.

Here is a picture of factory ThirdGen Clamshells:



Here's a couple pictures to show the way the factory motor mounts are built and need to be installed.

Factory Motor Mount Passenger Side:


Factory Motor Mount Driver Side:



The first time I installed these headers I didn't catch on and it was a real problem cause I did it to someone else's car. It was an 87 IROC with an LB9 that had previously run Edelbrock 6827's without a problem. Once the clearance problem was discovered Don was notified (5-27-12). The original motor mounts were removed and new POLY inserts were installed. This DID raise the height of the engine seemingly enough to correct the problem; but after some use it's still a problem.

The Second time I installed this set was a month or 2 later on my own car. (LT1 w T56) It had used several types of headers over the years without a problem - most recently Hooker 2640's. I had requested to Don (knowing there had been a clearance issue) that quality take priority over speed of the product and a little over a month after payment the Dyno Don's headers arrived. I place the drivers side header against the head and could not get the rear bolt installed. The header would not move forward far enough because it was hitting the K member. SO,... I bought new POLY inserts.



After installing the Poly Mounts I was able to get 1 rear and 1 front bolt thru the flange and into the head WITHOUT a gasket in place and the flange was still not flush to the head. I bought the recommended Earl's gaskets ( EAR-29DD3BERL ) and this is the gap once gaskets were set into place.



The contact point is very easy to see.....



I was left with notching the K member. After 6 or 7 iterations of grinding and fitting I had removed enough of the K member removed to get the header and gasket "flush" to the head.



I had to shave so much metal that a small hole formed; the fresh paint shows the shaved area and the small hole is visible next to the relocated brake line.




Once the gaskets were installed and bolts were all tourqed down I find that I'm BARELY clear of the K member in that spot and pretty certain It will make contact again under load. At this point I'm totally 'done' and the next time I address this problem it will be with a prybar and a hammer.

My Poly Mounts are installed correctly, the Motor mounts were re-built correctly, My Clamshells are in the correct locations,. I do not have a problem on the passenger side. There is PLENTY of room between the drivers side flange and the block. I can fit my fingers thru the gap,.... and I've got an oil cooler installed. If the collector was moved towards the block just a little when they were made - this would have been a 1/2 hour install rather than a months long saga. I bought these headers cause they were highly recommended by other members. After almost a Thousand dollars into parts specifically for this part of my project - and after 2-3 months of aggravation and effort - I'm a bit disturbed that things didn't go 'better'. Once the motor is up and running,.... I sure hope the headers perform !

IROCZ1989

iTrader: (1)

Im having issues with my y pipe hitting the frame. From the pics it looks like I have 2 drivers side mounts passenger has 14037877 stamped on the front. I have poly mounts. My only close point is the passanger side header pipes are real close like an 1/8 from the frame rail sides. Motor doesn't torque that way so i should be good and the poly mounts hold it real tight. Idk Drivers side i have a ton of clearance. My poly mounts the tabs are in correct. Just my mounts are the same off the block. Im pretty sure these were my factory mounts but mines an 89 gm could have swapped stuff to save money. Motor sits completely straight in engine bay. Im thinking if I had the taller mount on the passenger side the header would def hit the frame. Ill post some pics later if I can John. Ttys

The Project

iTrader: (6)

Great pics John.

Will come in handy when I reinstall the k-mem and motor.